What is food chemistry. Chemistry in the food industry. Nutritional supplements, what are they?

All industries Food Industry are inextricably linked with the development of chemistry. The level of development of biochemistry in most branches of the food industry also characterizes the level of development of the industry.

As we have already said, the main technological processes of the wine, bakery, brewing, tobacco, food, acid, juice, fermented, and alcohol industries are based on biochemical processes. That is why the improvement of biochemical processes and, in accordance with this, the implementation of measures to improve the entire production technology is the main task of scientists and industry workers. Workers at a number of industries are constantly engaged in breeding - the selection of highly active races and strains of yeast. After all, the yield and quality of wine and beer depend on this; yield, porosity and taste of bread. Serious results have been achieved in this area: our domestic yeast, in terms of its “performance”, meets the increased requirements of technology.

An example is the K-R race yeast, developed by the workers of the Kyiv Champagne Wine Factory in collaboration with the Academy of Sciences of the Ukrainian SSR, which performs well fermentation functions under the conditions of the continuous process of champagne wine; Thanks to this, the champagne production process was reduced by 96 hours. For the needs of the national economy, tens and hundreds of thousands of tons of edible fats are consumed, including a significant share for the production detergents and drying oils. Meanwhile, in the production of detergents, a significant amount of edible fats (with the current level of technology - up to 30 percent) can be replaced with synthetic fatty acids and alcohols. This would release a very significant amount of valuable fats for food purposes.

For technical purposes, for example, for the production of adhesives, it is also spent a large number of(many thousands of tons!) of food starch and dextrin. And here chemistry comes to the rescue! Back in 1962, some factories began to use synthetic material - polyacrylamide - for labeling instead of starch and dextrin. Currently, most factories - wineries, beer-soft drinks, champagne, canning, etc. - are switching to synthetic adhesives. Thus, synthetic glue AT-1, consisting of MF-17 resin (urea with formaldehyde) with the addition of CMC (carboxymethylcellulose), is increasingly used.

The food industry processes a significant amount of food liquids (wine materials, wines, beer, beer wort, kvass wort, fruit and berry juices), which by their nature have aggressive properties towards metal. These liquids are sometimes contained during the technological processing in unsuitable or poorly adapted containers (metal, reinforced concrete and other containers), which deteriorates the quality of the finished product.

Today, chemistry has introduced many different coating products to the food industry. internal surfaces various containers - reservoirs, tanks, apparatus, tanks. These are eprosin, varnish XC-76, HVL and others, which completely protect the surface from any impact and are completely neutral and harmless. Synthetic films, plastic products, and synthetic closure materials are widely used in the food industry.

In the confectionery, canning, food concentrate, and baking industries, cellophane is successfully used for packaging various products. Bakery products are wrapped in plastic film, and they retain freshness better and longer and become stale more slowly.

Plastics, cellulose acetate film and polystyrene are increasingly used every day for the manufacture of containers for packaging confectionery products, for packaging jam, jam, preserves and for the preparation of various boxes and other types of packaging. Expensive imported raw materials - linings made of cork wood for capping wine, beer , soft drinks, mineral waters - perfectly replace various types of gaskets made of polyethylene, polyisobutylene and other synthetic masses.

Chemistry also actively serves the food engineering industry. Nylon is used for the manufacture of wear parts, caramel stamping machines, bushings, clamps, silent gears, nylon meshes, filter fabric; In the wine, alcoholic beverage and beer and non-alcoholic industries, nylon is used for parts for labeling, rejecting and filling machines.

Every day, plastic masses are increasingly being “introduced” into food engineering - for the manufacture of various conveyor tables, bunkers, receivers, elevator buckets, pipes, bread proofing cassettes and many other parts and assemblies.

The contribution of big chemistry to the food industry is steadily growing,

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Food chemistry- a section of experimental chemistry that deals with the creation of high-quality food products and analytical methods in the chemistry of food production.

The chemistry of food additives controls their introduction into food products to improve production technology, as well as the structure and organoleptic properties of the product, increase its shelf life, and increase biological value. These additives include:

• stabilizers
• flavoring agents and aromas
• taste and smell intensifiers
• spices

The creation of artificial food is also a subject of food chemistry. These are products that are obtained from proteins, amino acids, lipids and carbohydrates, previously isolated from natural raw materials or obtained by directed synthesis from mineral raw materials. They are supplemented with food additives, as well as vitamins, mineral acids, microelements and other substances that give the product not only nutritional value, but also color, smell and the necessary structure. As natural raw materials, secondary raw materials from the meat and dairy industries, seeds, green mass of plants, hydrobionts, and biomass of microorganisms, such as yeast, are used. From these, high molecular weight substances (proteins, polysaccharides) and low molecular weight substances (lipids, sugars, amino acids and others) are isolated using chemical methods. Low molecular weight nutrients are also obtained by microbiological synthesis from sucrose, acetic acid, methanol, hydrocarbons, enzymatic synthesis from precursors, and organic synthesis (including asymmetric synthesis for optically active compounds). There are synthetic foods obtained from synthesized substances, for example, diets for therapeutic nutrition, combined products from natural products with artificial food additives, for example, sausages, minced meat, pates, and analogues food products, imitating any natural products, for example, black caviar.

Literature

1. Nesmeyanov A. N. Food of the future. M.: Pedagogy, 1985. - 128 p.
2. Tolstoguzov V.B. New forms of protein food. M.: Agropromizdat, 1987. - 303 p.
3. Ablesimov N. E. Synopsis of chemistry: Reference and textbook on general chemistry - Khabarovsk: Publishing House FEGUPS, 2005. - 84 p. - http://www.neablesimov.narod.ru/pub04c.html
4. Ablesimov N. E. How many chemistries are there in the world? Part 2. // Chemistry and life - XXI century. - 2009. - No. 6. - P. 34-37.

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• Food chemistry, . The book examines the chemical composition of food systems, its usefulness and safety. The main transformations of macro- and micronutrients in the process stream, fractionation...

Kopacheva Ekaterina, Krasnenkova Daria, Penkova Nina, Stepanova Daria.

ABSTRACT OF THE PROJECT WORK

1. Project nameChemistry in the food industry

2.Project managerKuzmina Marina Ivanovna

3. Academic subject within which the project work is carried out:chemistry

4. Academic disciplines close to the topic project: biology

5. Composition of the project team

Kopacheva Ekaterina 10 B,

Krasnenkova Daria 10 B,

Penkova Nina 10 B,

Stepanova Daria 10 B.

6 . Project type:

research

7. Relevance.

Currently, chemicals are widely used in the food industry. Errors in the use of these products may result in sad consequences. The “Chemistry in the Food Industry” project will allow us to increase the level of knowledge in this area, which people encounter every day, and to protect our body from harmful food additives.

8. Hypothesis.

Drinks and chocolate contain many food additives. Some of these food additives may have harmful effects on the human body. Research will help avoid consuming chocolate and drinks containing such substances.

9. Project goals:

determination of the content of food additives in drinks and chocolate.

10. Project objectives:

- Give a theoretical description of food additives;

-Analyze the composition of drinks and chocolate (for the presence of food additives) according to the labels;

-Provide an overview of diseases of non-microbial etiology caused by food additives;

-Summarize the results in the form of a presentation *Chemistry in the food industry*

11. Description of the results.

We analyzed drinks and chocolate for the presence of food additives, and presented the results in table form.

Through food research, we have learned that their consumption is harmless to humans.

12. References

Internet,

electronic encyclopedia Wikipedia,

Preservatives in the food industry, “Chemistry at school”, No. 1, 2007, p. 7.,

Chemical experiments with chocolate, “Chemistry at school”, No. 8, 2006, p. 73.

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Project work On the topic: Chemistry in the food industry

Purpose of the work: Study of the hygienic aspects of the use of food additives in food products. Objectives: Give a theoretical description of food. additives; Provide an overview of diseases of non-microbial etiology caused by them; Do general analysis for the presence (or absence) of food. Additives in food products in Moscow

Relevance of the problem Modern man has become so adapted to active life that I stopped paying attention to such little things as healthy eating. Nowadays, the trend is something that you can eat *on the run* and get full quickly. But people forget that such food contains more harmful substances that have a detrimental effect on our health. We decided to conduct some research in this area (food products and their composition) and identify products that are less harmful to human health. The study will focus on commonly consumed foods such as chocolate and carbonated drinks.

Classification of food additives E100-E182 – dyes E200-E280 – preservatives E300-E391 – antioxidants; acidity regulators E400-E481 – stabilizers; emulsifiers; thickeners E500-E585 – various E600-E637 – flavor and aroma enhancers E700-E899 – spare numbers E900-E967 – anti-foam, glazing agents; improved flour; sweeteners E1100-E1105 – enzyme preparations Banned in the Russian Federation: E121 – citrus red 2-dye E173-aluminium; E240 – formaldehyde preservative

Description of food additives Organic acids: - food acidity regulators; -antioxidants; - preservatives; -emulsifiers; - taste and smell enhancers; Food flavorings; Natural sweeteners; Synthetic sweeteners; Natural food colors; Synthetic dyes.

Food additives Food additives are substances added to food products to give them desired properties, for example, a certain aroma (flavors), color (dyes), shelf life (preservatives), taste, consistency.

Regulators of food acidity. Products Acidity regulators are substances that establish and maintain a certain pH value in a food product. Adding acids lowers the pH of the product, adding alkalis increases it, and adding buffers maintains the pH at a certain level. Acidity regulators are used in the production of beverages, meat and fish products, marmalades, jellies, hard and soft caramels, sour dragees, chewing gum, and chewing candies.

Antioxidants Antioxidants protect fats and fat-containing products from burning, protect vegetables, fruits and their processed products from darkening, and slow down the enzymatic oxidation of wine, beer and soft drinks. It is widely believed that antioxidants can prevent the damaging effects of free radicals on the cells of living organisms, and thereby slow down the aging process. However, numerous research results have not confirmed this hypothesis.

Preservatives Preservatives are substances that inhibit the growth of microorganisms in a product. In this case, as a rule, the product is protected from the appearance bad taste and odor, molding and the formation of microbial toxins. There is a widespread belief that many preservatives are harmful due to their ability to inhibit the synthesis of certain proteins. The degree of their involvement in blood diseases, or cancer diseases not proven due to insufficient research in this area. However, some nutritionists do not recommend consuming large quantities products that contain artificial preservatives.

Emulsifiers Emulsifiers are substances that create emulsions from immiscible liquids. Emulsifiers are often added to foods to create and stabilize emulsions and other food disperse systems. Emulsifiers determine the consistency of a food product, its plastic properties, viscosity and the feeling of “fullness” in the mouth. Superficial Active Substances Most are synthetic substances that are not resistant to hydrolysis. In the human body, they are broken down into natural, easily digestible components: glycerin, fatty acids, sucrose, organic acids (tartaric, citric, lactic, acetic).

Emulsifiers

Flavor and smell enhancers Fresh vegetables, meat, fish and other products have a bright taste and aroma due to the nucleotides they contain. During storage and industrial processing, the amount of nucleotides decreases, which is accompanied by a loss of taste and aroma of the product. The GIORD company produces a taste and aroma enhancer Glurinate (also glutamate), which enhances the perception of taste and smell by influencing the taste buds of the mouth. Currently, there is no significant effect of monosodium glutamate on the human body. However, there have been cases of allergic reactions when eating certain foods high in it.

Flavorings Food flavorings are food additives that give food products the necessary taste and aroma characteristics. They are used in the food industry to restore or enhance organoleptic properties, since smell and taste can be lost during storage and production of products. Flavorings identical to natural include vanillin, raspberry ketone, ethyl acetate, amyl acetate, ethyl formate and others. Flavorings in high concentrations, and at long-term use, can cause, in particular, liver dysfunction. Flavorings such as ionone and citral have an effect in animal experiments Negative influence on metabolic processes. Their use in the production of baby food is excluded

Sweeteners Sweeteners are substances used to impart a sweet taste. Natural and synthetic substances are widely used to sweeten foods, drinks, and medicines.

Colors Colors are added to food products to restore natural color lost during processing or storage, to enhance natural color and color colorless products (e.g. soft drinks, ice cream, confectionery), and to provide attractive appearance and color variety to foods.

Food colors that dissolve in a thin film of water

Analysis of some types of chocolate Comparison line Chocolate varieties Nesquik Picnic Kinder Alpen Gold Alenka No. 1 Alenka No. 2 Milky Way Ferrero Rocher 1. Presence of the GOST or TU mark TU 9123-031-00334675 TU 9123-002-45257475-03 - TU 9125-007- 4049419 MSISO 9001 TU-9120-031-00340635 GOST RISO 9001-2001 TU 9125-012-003400664 GOST RISO 9001-2001 TU 9125-026-11489576 - 2. Presence of sign acc. Ross. standard. (PCT) + + + + + + + + 3. Presence of an eco-label. purity - - - - - - - - 4. Fat content % 4.5 3 2.9 3 3 2.8 5.3 2.4 5. Salinity - + - - - - - + 6. Presence of vegetables. fat + + + - - - + - 7. Presence of belly. fat + - + + - - + +

Comparison line Chocolate varieties Nesquik Picnic Kinder Alpen Gold Alenka No. 1 Alenka No. 2 Milky Way Ferrero Rocher 8. Availability of food additives 1. Regulated acid. - - - Lim. sour - Tokamix - - 2. antioxidant. - - - - - - - - 3. preservatives - - - - - - - - 4. emulsifiers E476, E322 E322, E471, E476 E322 E322, E476 E322 E322, E476 E322 E322 5. flavoring. + + + + + + + + 6. sweeten. - - - - - - - - 7. dyes - - - - - - - -

Notes to table No. 1 E476-poiplicerin, polyricinoleate - food. additive (reduces the viscosity of chocolate, reduces fat content) – does not cause harm. influence on the human body E322-soy lecithin E471-mono and diglycerides (harmful) Tokamix-E306-antioxidant, stabilizer for fats and oils

Analysis of some types of soft drinks Pepsi Coca-Cola Blackberries with taiga herbs Tarragon Preservatives Carbon dioxide E290 Carbon dioxide E290 Sodium benzoate E211 Potassium sorbate E202 Preservative Sodium benzoate E211 Acidity regulators E338-orthophosphorus. Kit E338-orthophosphorus. Additives - - Antioxidants - - Citric acid Citric acid Emulsifiers - - - - Flavors Natural flavor *Pepsi* Natural flavor - Flavor identical to natural *tarragon* Sweeteners - - *Sweetland 200M* - Dyes E150a sah. Color I - color dye. colors Sugar color IV Caramel color - Other features Caffeine content in the drink (no more than 110 mg/l) Caffeine content in the drink (alkaloid) Concentrated blackberry juice; natural concentrated base *Eleutheroccus with herbs* Contents in the drink herbs with tarragon extract PCT; TU 9185-001-17998155 RCT; TU 9185-473-00008064-2000 RCT; TU 9185-011-48848231-99 Ecological. pure PCT product; GOST 28 188-89

Notes to table No. 2 E290-carbon dioxide - preservative Sodium benzoate - E211-preservative. Protects products from mold and fermentation. Potassium sorbate - E202-Potassium sorbate is a preservative that actively inhibits yeast, mold fungi, some types of bacteria, and also inhibits the action of enzymes. Due to this, the shelf life of the products increases. Potassium sorbate does not have a microbicidal effect; it only slows down the development of microorganisms. E338-orthophosphoric acid-acidity regulator E150a-sugar color I simple (brown) Caffeine-alkaloid

Impact on human health A little higher (when describing supplements) the side effects of their consumption were also given. These were mainly personal intolerances in the form of allergic reactions. The following additives have side effects: -E211-cancer-forming (controversial) -E471-harmful additive -E150a-suspicious additive -Caffeine - contraindicated for: increased. excitability, insomnia, increased pressure, atherosclerosis, glaucoma, heart disease, old age. age

General conclusions from the research Summing up the results of the research, it remains to say that moderate consumption The chocolate shown in the table (with the exception of Picnic "a, the complete safety of which the research group doubts) and carbonated drinks do not cause particular harm to human health, because they do not contain excessive amounts of harmful substances. Frequent consumption of carbonated drinks is not recommended, because They contain questionable substances that can affect the human body.

Three kilograms of chemicals. This is the amount that is swallowed per year by the average consumer of a wide variety of, sometimes absolutely familiar, products: muffins, for example, or marmalade. Dyes, emulsifiers, sealants, thickeners are now present in literally everything. Naturally, the question arises: why do manufacturers add them to food and how harmless are these substances?

Experts have agreed that “food additives are the general name for natural or synthetic chemicals added to food products in order to give them certain properties (improving taste and smell, increasing nutritional value, preventing product spoilage, etc.) that are not are consumed as independent food products.” The wording is quite clear and understandable. However, not everything in this matter is simple. Much depends on the honesty and basic decency of manufacturers, on what exactly and in what quantities they use to give products a marketable appearance.

Serial number of taste

Nutritional supplements are not an invention of our high-tech age. Salt, soda, and spices have been known to people since time immemorial. But the real flourishing of their use began in the twentieth century, the century of food chemistry. There were high hopes for supplements. And they fully met expectations. With their help, it was possible to create a large assortment of appetizing, long-lasting and at the same time less labor-intensive products. Having won recognition, the “improvers” were put into production. The sausages turned soft pink, the yoghurts became freshly fruity, and the muffins were fluffy and unstale. The “youth” and attractiveness of the products is ensured by additives that are used as dyes, emulsifiers, sealants, thickeners, gelling agents, glazing agents, flavor and odor enhancers, and preservatives.

Their presence is necessarily indicated on the packaging in the list of ingredients and is designated by the letter “E” (the initial letter in the word “Europe”). You should not be afraid of their presence; most items are correct observance the formulation does not pose any harm to health, the only exceptions being those that may cause individual intolerance in some people.

The letter is then followed by a number. It allows you to navigate the variety of additives, being, according to the Unified European Classification, a code for a specific substance. For example, E152 is completely harmless activated carbon, E1404 is starch, and E500 is soda.

Codes E100E182 designate dyes that enhance or restore the color of the product. Codes E200E299 preservatives that increase the shelf life of products by protecting them from microbes, fungi and bacteriophages. This group also includes chemical sterilizing additives used during the ripening of wines, as well as disinfectants. E300E399 antioxidants that protect products from oxidation, for example, from rancidity of fats and discoloration of cut vegetables and fruits. E400E499 stabilizers, thickeners, emulsifiers, the purpose of which is to maintain the desired consistency of the product, as well as increase its viscosity. E500E599 pH regulators and anti-caking agents. E600E699 flavorings that enhance the taste and aroma of the product. E900E999 anti-flaming agents (defoamers), E1000E1521 everything else, namely glazing agents, separators, sealants, flour and bread improvers, texturizers, packaging gases, sweeteners. There are no food additives under the numbers E700E899 yet; these codes are reserved for new substances, the appearance of which is not far off.

The secret of the crimson kermes
The history of such food coloring as cochineal, also known as carmine (E120), is reminiscent of a detective novel. People learned to receive it in ancient times. Biblical legends mention a purple dye derived from the red worm, which was consumed by the descendants of Noah. Indeed, carmine was obtained from cochineal insects, also known as oak mealybugs, or kermes. They lived in Mediterranean countries, were found in Poland and Ukraine, but the Ararat cochineal received the greatest fame. Back in the 3rd century, one of the Persian kings gave the Roman emperor Aurelian a woolen fabric dyed crimson, which became a landmark of the Capitol. Ararat cochineal is also mentioned in medieval Arab chronicles, which say that Armenia produces “kirmiz” paint, used for coloring down and woolen products and writing book engravings. However, in the 16th century, a new type of cochineal Mexican appeared on the world market. The famous conquistador Hernan Cortes brought it from the New World as a gift to his king. The Mexican cochineal was smaller than the Ararat cochineal, but it reproduced five times a year, there was practically no fat in its slender bodies, which simplified the paint production process, and the coloring pigment was brighter. In a matter of years, a new type of carmine conquered all of Europe, but the Ararat cochineal was simply forgotten for many years. The recipes of the past were restored only at the beginning of the 19th century by Archimandrite of the Etchmiadzin Monastery Isaac Ter-Grigoryan, also known as miniaturist Sahak Tsakhkarar. In the 30s of the 19th century, Academician of the Russian Imperial Academy of Sciences Joseph Hamel became interested in its discovery, devoting an entire monograph to “living dyes.” They even tried to breed cochineal on an industrial scale. However, the appearance of cheap aniline dyes at the end of the 19th century discouraged domestic entrepreneurs from tinkering with “worms”. However, it quickly became clear that the need for cochineal dye would not disappear very soon, because, unlike chemical dyes, it is absolutely harmless to the human body, which means it can be used in cooking. In the 30s of the twentieth century, the Soviet government decided to reduce the import of imported food products and obliged the famous entomologist Boris Kuzin to establish the production of domestic cochineal. The expedition to Armenia was a success. A valuable insect has been found. However, its breeding was prevented by the war. The project to study the Ararat cochineal was resumed only in 1971, but it never got to the point of breeding it on an industrial scale.

Food of tomorrow

August 2006 was marked by two sensations at once. At the International Congress of Mycologists, held in the Australian city of Cairns, Dr. Marta Taniwaki from the Brazilian Institute of Food Technology reported that she was able to uncover the secret of coffee. Its unique taste is due to the activity of fungi that enter the coffee beans during their growth. At the same time, what kind of fungus will be and how much it will develop depends on natural conditions the area in which the coffee is grown. That is why different varieties invigorating drinks are so different from each other. This discovery, according to scientists, has a great future, because if you learn to cultivate fungi, you can add a new taste not only to coffee, but, if you go further, to wine and cheese.

But the American biotechnology company Intralytix proposed using viruses as food additives. This know-how will make it possible to cope with outbreaks of such a dangerous disease as listeriosis, which, despite all the efforts of health officials, annually kills about 500 people in the United States alone. Biologists have created a cocktail of 6 viruses that are destructive to the bacterium Listeria monocytogenes, but absolutely safe for humans. The US Food and Drug Administration (FDA) has already given the go-ahead for the processing of ham, hot dogs, sausages, sausages and others. meat products.

The saturation of foods with special nutrients, practiced in recent decades in developed countries, has made it possible to almost completely eliminate diseases associated with a deficiency of one or another element. This is how cheilosis, angular stomatitis, glossitis, seborrheic dermatitis, conjunctivitis and keratitis associated with a lack of vitamin B2, riboflavin (dye E101, which gives products a beautiful yellow); scurvy caused by deficiency of vitamin C, ascorbic acid (antioxidant E300); anemia, caused by a lack of vitamin E, tocopherol (antioxidant E306). It is logical to assume that in the future it will be enough to drink a special vitamin-mineral cocktail or take the appropriate pill, and nutrition problems will be solved.

However, scientists do not think of stopping there; some even predict that by the end of the 21st century our diet will consist entirely of food additives. It sounds fantastic and even somewhat scary, but we must remember that similar products already exist. Thus, chewing gum and Coca Cola, which were super popular in the 20th century, got their unique taste thanks to food additives. But society does not share such enthusiasm. The army of opponents of food additives is growing by leaps and bounds. Why?

EXPERT OPINION
Olga Grigoryan, presenter Researcher Department of Preventive and Rehabilitative Dietetics of the Clinical Nutrition Clinic of the State Research Institute of Nutrition of the Russian Academy of Medical Sciences, Ph.D. medical sciences.
In principle, there is nothing strange in the fact that any chemical fillers, without which the modern food industry is unthinkable, are fraught with allergic reactions and malfunctions gastrointestinal tract. However, it is extremely difficult to prove that it was this or that food additive that caused the disease. You can, of course, exclude a suspicious product from the diet, then introduce it and see how the body perceives it, but the final verdict: which substance caused the allergic reaction can only be made after a series of expensive tests. And how will this help the patient, because next time he can buy a product on which this substance simply will not be indicated? I can only recommend avoiding beautiful products with unnatural colors and too intrusive tastes. Manufacturers are well aware of the possible risks of using food additives and take them quite consciously. Appetizing look meat products, which is caused by the use of sodium nitrite (preservative E250), has long become the talk of the town. Its excess has a negative effect on metabolic processes, has a depressant effect on the respiratory system, and has an oncological effect. On the other hand, it’s enough to look at homemade sausage once gray to understand that in this case the lesser of two evils is chosen. And, in order not to create problems for yourself and not to exceed the maximum permissible concentration of sodium nitrite, do not eat sausage every day, especially smoked one, and everything will be fine.

Passions flare up

The problem is that not all food additives used in the industry are well studied. A typical example is sweeteners, artificial sugar substitutes: sorbitol (E420), aspartame (E951), saccharin (E954) and others. For a long time, doctors considered them absolutely safe for health and prescribed them to patients diabetes mellitus and those who simply want to lose weight. However, in the last two decades it has been discovered that saccharin is a carcinogen. In any case, laboratory animals who consumed it suffered from cancer, although only if they ate saccharin in a volume comparable to their own weight. Not a single person is capable of this, and therefore risks much less. But a large amount of sorbitol (about 10 grams or more) can cause gastrointestinal failure and cause diarrhea. In addition, sorbitol can worsen irritable bowel syndrome and fructose malabsorption.

The history of food additives in the 21st century has also been marked by scandal. In July 2000, representatives of the American Society for the Protection of Consumer Rights, with the support of Connecticut State Attorney Richard Blumenthal, appealed to the US Food and Drug Administration (FDA) with a demand to suspend the sale of food products fortified with certain substances. In particular, it was about orange juice with calcium, cookies with antioxidants, margarine, which lowers the level of “bad” cholesterol, cakes with dietary fiber, as well as drinks, breakfast cereals and chips with vegetable-based additives. Arguing his claim, Richard Blumenthal stated, based on some evidence, that “certain additives may interfere with the action of medications. "Obviously there are other side effects that have not yet been discovered." Like looking into the water. Three months later, a group of French researchers studying the properties of dietary fiber announced that not only does it not protect against bowel cancer, but it can also provoke it. For three years, they observed 552 volunteers with precancerous changes in the intestines. Half of the subjects ate as usual; the other half were given an additive based on isphagula husks. And what? In the first group, only 20% got sick, in the second - 29%. In August 2002, Belgian Health Minister Magda Elwoert added fuel to the fire by calling on the leadership of the European Union to ban chewing gum and fluoride tablets in the EU, which, of course, protect against caries, but, on the other hand, provoke osteoporosis.

In January 2003, food dyes, or more precisely, one of them, canthaxanthin, came into the spotlight of public attention. People don’t use it as food, but they add it to salmon, trout, and chickens’ feed so that their meat becomes beautiful colour. An EU commission found that “there is a compelling link between increased consumption of canthaxanthin in animals and vision problems in humans.”

However, the report of British professor Jim Stevenson, published in the spring of 2003, created a real sensation. The object of the study by scientists from the University of Southampton (UK) were five-year-old twins Michael and Christopher Parker. For two weeks, Michael was not allowed to eat Smarties and Sunny Delight candies, red drinks Irn Bru and Tizer, as well as carbonated drinks and other foods with chemical additives. The twins' mother, Lynn Parker, described the results of the experiment as follows: “On the second day, I saw changes in Michael’s behavior. He has become much more obedient, he has developed a sense of humor, and he talks willingly. The level of stress in the house has decreased, there is less aggression in the relationships between the boys, they hardly fight or quarrel.” Scientists from Australia also reported on the effect of food additives on the behavior of adolescents. They determined that calcium propionate (E282), added to bread as a preservative, can lead to severe mood swings, sleep disturbances and problems with concentration in children.

In April 2005, an international team of researchers led by Malcolm Greaves reported that food additives (colors, seasonings and preservatives) are responsible for 0.6-0.8% of cases of chronic urticaria.

Black list
Food additives prohibited for use in the food industry of the Russian Federation
E121 Citrus red 2
E123 Red amaranth
E216 Parahydroxybenzoic acid propyl ester
E217 Parahydroxybenzoic acid propyl ester sodium salt
E240 Formaldehyde

Just a few years ago, prohibited additives that clearly pose a threat to life were used very actively. Dyes E121 And E123 contained in sweet carbonated water, candies, colored ice cream, and the preservative E240 in various canned foods (compotes, jams, juices, mushrooms, etc.), as well as in almost all widely advertised imported chocolate bars. Preservatives were banned in 2005 E216 And E217, which were widely used in the production of sweets, filled chocolate, meat products, pates, soups and broths. Studies have shown that all of these additives can contribute to the formation of malignant tumors.

Food additives prohibited for use in the EU food industry, but permitted in the Russian Federation
E425 Konjac (Konjac flour):
(I) Konjac gum,
(II) Konjac glucomannan
E425 used to speed up the process of combining poorly mixed substances. They are included in many products, especially the Light type, such as chocolate, in which vegetable fat replaced with water. It is simply impossible to do this without such additives.
E425 does not cause serious illnesses, but in the EU countries konjac flour is not used. It was withdrawn from production after several cases of suffocation of small children were recorded, in Airways which ingested chewing marmalade, which was poorly soluble in saliva, the high density of which was achieved through this additive.

Life truth

We must also take into account the fact that, due to his psychology, a person often cannot refuse what is harmful, but tasty. Indicative in this regard is the story of the taste enhancer monosodium glutamate (E621). In 1907, Kikunae Ikeda, an employee of the Imperial University of Tokyo (Japan), first obtained a white crystalline powder, which enhanced the sense of taste by increasing the sensitivity of the papillae of the tongue. In 1909, he patented his invention, and monosodium glutamate began its victorious march around the world. Currently, the inhabitants of the Earth annually consume more than 200 thousand tons of it, without thinking about the consequences. Meanwhile, more and more data is appearing in the specialized medical literature that monosodium glutamate has a negative effect on the brain, worsens the condition of patients with bronchial asthma, and leads to destruction of the retina and glaucoma. It is monosodium glutamate that some researchers blame for the spread of “Chinese restaurant syndrome.” For several decades now, a mysterious disease has been recorded in various parts of the world, the nature of which is still unclear. Absolutely healthy people out of the blue, the temperature rises, the face turns red, and chest pain appears. The only thing that unites the victims is that, shortly before their illness, they all visited Chinese restaurants, whose chefs tend to abuse the “tasty” substance. Meanwhile, according to the WHO, taking more than 3 grams of MSG per day “is very hazardous to health.”

And yet we must face the truth. Today, humanity cannot do without food additives (preservatives, etc.), since it is they, and not Agriculture, are capable of providing 10% of the annual increase in food supply, without which the world's population will simply be on the verge of starvation. Another question is that they should be as safe as possible for health. Sanitary doctors, of course, take care of this, but everyone else should not lose their vigilance, carefully reading what is written on the packaging.

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Federal Agency for Education of the Russian Federation

Kemerovo Technological Institute of Food Industry

Department of Fermentation and Canning Technologies

Training and metodology complex

for full-time and part-time students

majoring in “Technology of fermentation production and winemaking”

Food chemistry

Preface

The educational and methodological complex for the course “Food Chemistry” is intended to familiarize you with the theoretical materials of the course “Food Chemistry” being studied, and includes a laboratory workshop for performing laboratory work, requirements for the preparation of tests for part-time students, options for tests for part-time students, questions for the test in the course “Food Chemistry”.

The purpose of studying the discipline “Food Chemistry” is for students to gain knowledge about the chemical composition of food raw materials, semi-finished products, finished products, about the general laws of chemical processes that occur during the processing of raw materials into the finished product, about the role of the main components of food in the life of the human body. Familiarity with the procedure for calculating the nutritional and energy value of food products.

The objective of the discipline is to study the main constituents of food products and their role in human nutrition; familiarization with the basic chemical processes occurring as a result of storage and processing of raw materials into a finished product, with standards daily consumption nutrients. Learning Theory rational nutrition person.

The knowledge acquired by students while studying the course “Food Chemistry” is based on the knowledge gained from studying the disciplines “ Organic chemistry", "Biochemistry", and in the course of further training, they are consolidated and deepened by studying special disciplines: "Industry Technology", "Industry Chemistry".

As a result of studying this discipline, students must-

KNOW: The main components of food products, their daily consumption and role in the physiology of human nutrition; the main transformations of the constituent substances of food in the human body and in the process of processing raw materials into finished products.

BE ABLE TO: Calculate the nutritional and energy value of products and its change with the introduction of new additives; identify the main components of raw materials, semi-finished products, finished products; predict changes in the composition and properties of food products when various types technological processing of raw materials and semi-finished products.

Lecture notes include the main sections of the course being studied.

The knowledge acquired by students while studying the course “Food Chemistry” is further consolidated and deepened when studying special disciplines.

Before taking the test, students must work through the theoretical material both presented in this textbook and presented in lecture material and specialized literature.

The “Food Chemistry” course program is compiled on the basis of the State educational standard higher vocational education in the direction 655600 “Production of food products from plant raw materials” for specialty 260402 “Technology of fermentation production and winemaking”, approved on March 23, 2000, state no. reg. 185tech/ds.

The program contains a theoretical course, the content of which is given in detail in the presented methodological complex. In addition, the program of the discipline “Food Chemistry” includes laboratory work for students of all forms of study, and a test for correspondence students. The content of laboratory work is given in the laboratory workshop.

Introduction. Subject and objectives of the course. Promotion problems nutritional value, food quality and safety, the role of chemical transformations that occur during the production and storage of food products. Macro and micronutrients of food raw materials. Their transformation in the process of storage and processing of food raw materials.

Basics of rational nutrition. Brief information about the chemistry of digestion. Basic principles of the theory of balanced nutrition. Determination of nutritional and energy value of food products.

Carbohydrates of raw materials and finished products. Characteristics of carbohydrates of raw materials and finished products of fermentation plants: mono-, oligo- and polysaccharides. The main transformations of carbohydrates during the storage and processing of raw materials into finished products: chemical transformations (inversion, reversion, caramelization, oxymethylfurfural decomposition, melanoid formation reaction), enzymatic transformations (respiration, fermentation, hydrolysis). Technological role of carbohydrates. Nutritional value of carbohydrates.

Proteins of raw materials and finished products. Characteristics of amino acids, proteins of raw materials and finished products. Enzymatic and non-enzymatic transformations of nitrogenous substances during the processing of raw materials: (hydrolysis, coagulation and denaturation, foaming, hydration, melanoid formation). The role of nitrogenous substances in the formation of the quality of drinks. Nutritional value of proteins and amino acids.

Lipids of raw materials and finished products. Classification of lipids of raw materials and finished products, transformations in food production: hydrolysis, hydrogenation, oxidation. Nutritional value of lipids.

Food acids in raw materials and finished products. The role and importance of food acids in raw materials and food products. Changes in food acids during processing of raw materials.

Vitamins of raw materials and finished products. Classification of vitamins of raw materials and finished products. Daily intake and food sources of vitamins. Common reasons loss of vitamins in food products. Changes in vitamins caused by technological processes. Methods for preserving vitamins in food products. Fortification of food.

Minerals in food products. Role and significance minerals in raw materials and food products. Micro and macroelements, daily intake and food sources. The influence of minerals on the human body. Changes in the composition of mineral substances during technological processing of raw materials.

Phenolic substances of raw materials and finished products of fermentation industries. Classification of phenolic substances of raw materials and finished products. Transformations during processing and storage (enzymatic oxidation, changes in polyphenols under the influence of the chemical composition of the environment, metals). The role of phenolic substances in the formation of the quality of drinks. Ways to prevent the oxidation of polyphenols.

Enzymes of raw materials and food products. Classification of enzymes. The role and importance of enzymes in raw materials and food products. The influence of enzymes on the safety of food raw materials, raw material processing technology and food quality. Application of enzymes in food technologies.

Water in raw materials and food products. Free and bound moisture, water activity and food stability.

Ecology of food. Medical and biological requirements for food products. Creation healthy foods nutrition.

1. Basics of rational human nutrition

1.1 Chemistry of digestion

The set of processes associated with the consumption and assimilation in the body of substances that make up food is called digestion. Nutrition includes sequential processes of intake, digestion, absorption and assimilation in the body of nutrients necessary to cover energy costs, build and renew cells and tissues of the human body, as well as necessary to regulate body functions.

Products consumed by humans in natural or processed form are complex systems with a single internal structure and common physical and chemical properties. Food products have a diverse chemical nature and chemical composition.

Digestion is the initial stage of assimilation of nutrients. During the digestion process, food substances of complex chemical composition are broken down into simple soluble compounds that can be easily absorbed and absorbed by the human body.

The human digestive system includes the alimentary canal or gastrointestinal tract. The gastrointestinal tract includes:

Oral cavity,

Esophagus, stomach,

Duodenum,

Small intestine, large intestine,

Rectum,

The main glands are the salivary glands, liver, gallbladder, pancreas.

The transformation of nutrients in the digestion process occurs in three stages:

Cavity digestion: the digestion process occurs in the food cavities - oral, gastric, intestinal. These cavities are located away from the secretory cells (salivary glands, gastric glands). Cavity digestion provides intensive initial digestion.

Membrane digestion: carried out with the help of enzymes concentrated on microvilli located along the walls of the small intestine. Membrane digestion carries out the hydrolysis of nutrients.

Suction. Simple soluble substances that are formed during the digestion process are absorbed through the walls of the small and large intestines into the blood and are transported throughout the human body.

Each food component has its own pattern of digestion and assimilation.

Absorption of carbohydrates. From polysaccharides, starch contained in plant foods and glycogen contained in foods of animal origin are digested. Digestion of starch and glycogen occurs in stages.

The hydrolysis of starch and glycogen begins in the oral cavity under the action of amylase enzymes found in saliva. Hydrolysis then continues in the stomach and duodenum. Starch and glycogen are gradually broken down into dextrins, maltose, and glucose. The hydrolysis of dietary disaccharides is catalyzed by enzymes located in the outer layer of the epithelium of the small intestine. Sucrose, under the action of the enzyme sucrase (invertase), is broken down into glucose and fructose; lactose, under the action of the enzyme lactase (β-galactosidase), is broken down into galactose and glucose; maltose, under the action of the enzyme maltase, is broken down into two glucose molecules. Monosaccharides or simple hexoses are absorbed by intestinal epithelial cells into the blood and delivered to the liver.

Protein absorption. Food proteins are broken down by proteolytic enzymes into amino acids; the process occurs in the stomach, duodenum, and small intestine in stages.

In the stomach, protein digestion takes place in acidic environment, in the duodenum and intestines in a slightly alkaline environment. Various proteolytic enzymes are involved in the process of protein breakdown: pepsin, trypsin, aminopeptidase, carboxypeptidase and others.

Lipid absorption. The process takes place in the small intestine. The enzyme lipase is secreted by the pancreas. During the hydrolysis of lipids, under the influence of the lipase enzyme, free fatty acids, glycerol, phosphoric acid, and choline are formed. These components are emulsified by bile acids, then absorbed into the lymph, and from there they enter the blood.

Food products perform three main functions in the human body:

supply of material for the construction of human tissues;

providing the energy necessary to maintain life and perform work;

providing substances that play an important role in regulating metabolism in the human body.

1.2 Theory of balanced nutrition

The theory of rational nutrition is based on three main principles:

1. Energy balance. The energy supplied daily from food must correspond to the energy consumed by a person in the process of life.

2. Satisfying the body's needs for optimal quantity and the ratio of nutrients.

3. Diet. Compliance with a certain time and number of meals, rational distribution of food at each meal.

Energy balance. The energy that is provided to the body during the consumption and assimilation of nutrients is spent on the implementation of three main functions associated with the life of the human body. This includes: basal metabolism, food digestion, muscle activity.

Basal metabolism is the minimum amount of energy necessary for a person to maintain life at rest (during sleep). For men this energy is 1600 kcal, for women - 1200 cal.

Digestion of food is associated with the specific dynamic action of food in the absence of muscle activity. Due to the specific dynamic action of food, a person’s basal metabolism increases by 10-15%, which corresponds to 140-160 kcal per day.

Muscular activity is determined by the activity of a person’s lifestyle and the nature of a person’s work. 1000-2500 kcal are spent on muscle activity.

In total, a person spends 2200-2400 kcal for women and 2550-2800 kcal for men to perform all body functions. When performing heavy physical activity (sports, work of miners, builders, etc.), a person’s energy costs increase to 3500 - 4000 kcal. In the case of a positive energy balance over a long period of time, excess incoming energy is accumulated as fat in adipose tissue, which leads to excess body weight.

Satisfying the body's needs for the optimal quantity and ratio of nutrients. A complete diet should include five classes of nutrients: proteins (including essential amino acids), lipids (including essential fatty acids), carbohydrates (including dietary fiber), vitamins, and minerals.

The daily requirement of the human body for carbohydrates is 400-500 g, sucrose accounts for 10-20% of the total amount of carbohydrates. Carbohydrates are the main source of energy for humans. Dietary fiber - fiber, pectin, hemicelluloses stabilize activity digestive tract. Fiber and hemicelluloses cleanse the intestines, and pectin binds and removes from the body harmful substances. The daily requirement for dietary fiber is 25 g, for pectin - 5 g.

The daily requirement of the human body for lipids is 102 g, including 72 g from plants. Lipids are the main source of energy and are involved in the synthesis of cholesterol and other steroids. The optimal ratio of vegetable and animal fat is 7: 3. This ensures a balanced supply of various fatty acids: 30% saturated, 60% monounsaturated, 10% polyunsaturated fatty acids. The daily requirement for essential fatty acids (linoleic acid, linolenic acid) is 3 - 6 g.

Phospholipids, which are necessary for the renewal of cells and intracellular structures, are physiologically valuable. The daily requirement for phospholipids is 5 g.

The daily requirement of the human body for proteins is 85 g, including 50 g of animal proteins. Proteins supplied with food serve as building materials for the synthesis and renewal of proteins, provide hormonal metabolism, and are a source of energy. For normal nutrition the amount of essential amino acids in the diet should be 36 - 40%, which is ensured by the ratio of plant and animal proteins in food products to 45:55%.

Vitamins and vitamin-like substances are involved in the metabolism of substances in the human body, are part of coenzymes and enzymes, and influence metabolic processes in the human body. A person's need for vitamins should be satisfied through the consumption of natural products. The daily requirement for vitamins is shown in Table 6.1.

Minerals are necessary for normal nutrition, they perform various functions: they are part of the structural components of bones, they are electrolytes in maintaining the water-salt composition of blood and tissues, they are prosthetic groups in various enzymes, and they influence metabolic processes in the human body. The daily content of minerals in the diet is presented in Table 4.1. The optimal ratio of the main macroelements - calcium, phosphorus, magnesium should be 1: 1.5: 0.5 or in grams 800: 1200: 400.

It is very important with food to ensure that the body receives the necessary nutrients in optimal quantities and in right time. The need for various nutrients and energy depends on gender, age, the nature of a person’s work activity, climatic conditions and a number of other factors.

The consumption standards for the most important nutrients and energy for an adult are shown in Table 1.1.

The diet is based on four rules:

Regularity of nutrition,

Fractionality of food,

Rational selection of products,

Optimal distribution of food throughout the day.

Table 1.1 Nutrient and energy consumption standards

food substance	Daily requirement
Including animals
Essential amino acids, g
Digestible carbohydrates, g
Including mono- and disaccharides
Lipids, g Including herbal
Essential fatty acids, g
Phospholipids, g
Plant lipids, g
Dietary fiber, g Including pectin, g
Energy value, kcal

Regularity of nutrition is associated with observing meal times. A person develops a reflex to secrete digestive juice, which ensures normal digestion and absorption of food.

The dose of food should be 3-4 meals per day. When taken three times a day, breakfast should make up 30% of the diet, lunch 45-50%, and dinner 20-25%. Dinner should not exceed a third of the daily diet.

A rational selection of foods at each meal should provide optimal conditions for the absorption of food. Animal proteins are recommended to be consumed in the first half of the day, dairy and plant foods - in the second.

Optimal distribution of food throughout the day ensures an even load on the digestive system.

1.3 Determination of energy and nutritional value of food products

Based on the norms of human needs for basic nutrients and data on the chemical composition of food products, it is possible to calculate the nutritional value of the product, as well as create an individual diet.

The nutritional physiological value of a food product is understood as the balanced content of digestible essential substances in a food product: essential amino acids, vitamins, minerals, unsaturated fatty acids. The concept of nutritional value also includes the optimal ratio of proteins, fats, carbohydrates in food products, which is 1: 1.2: 4 or 85: 102: 360 grams. When calculating the nutritional value of a product, the percentage of nutrients in the product is determined: minerals (calcium, magnesium, etc.), vitamins (thiamine, ascorbic acid, etc.), from the optimal daily intake of this substance. Based on the results obtained, a conclusion is made about the usefulness or inferiority of the food product in terms of its composition.

The energy that is released from food substances in the process of biological oxidation is used to ensure the physiological functions of the body and determines the energy value of the food product.

The energy value of food products is usually expressed in kilocalories, calculated per 100 g of product. If recalculation is necessary in the SI system, a conversion factor of 1 kcal = 4.184 kJ is used. The conversion factors for the energy value of the most important components of raw materials and food products are:

Proteins - 4 kcal;

Carbohydrates - 4 kcal;

The sum of mono- and disaccharides is 3.8 kcal;

Fats - 9 kcal;

Organic acids - 3 kcal

Ethyl alcohol - 7 kcal.

Food products
Bread and bakery products in terms of flour
Potato
Vegetables and melons
Fruits and berries
Meat and meat products
Fish and fish products
Milk and dairy products expressed as milk
Whole milk
Skim milk
Animal oil (21.7)*
Cottage cheese (4.0)*
Sour cream and cream (9.0)*
Cheese, feta cheese (8.0)*
Eggs, pieces
Vegetable oil, margarine

To calculate the nutritional and energy value of products, it is necessary to know the chemical composition of the products. This information can be found in special reference books.

The energy value of the product is calculated using formula 1.1

E = (X protein Ch 4) + (X carbohydrates Ch4) + (X fats Ch 9) + (X organic acids Ch3) + (X alcohol Ch 7) (1.1)

Based on the level of energy value (calorie content), food products are divided into four groups:

Particularly high-energy (chocolate, fats) 400 - 900 kcal

High-energy (sugar, cereals) 250 - 400 kcal

Medium energy (bread, meat) 100 - 250 kcal

Low-energy (milk, fish, vegetables, fruits) up to 100 kcal

To perform all body functions, a person spends 2200-2400 kcal daily for women and 2550-2800 kcal for men. With increased physical activity, energy costs increase to 3500 - 4000 kcal.

2. Protein substances

2.1 Classification of proteins

Protein substances are high-molecular organic compounds whose molecules consist of residues of 20 different b-amino acids. Proteins play a huge role in the activities of living organisms, including humans. The most important functions of proteins are:

Structural function (connective tissues, muscles, hair, etc.); catalytic function (proteins are part of enzymes);

Transport function (transfer of oxygen by hemoglobin in the blood); protective function(antibodies, blood fibrinogen),

Contractile function (myosin of muscle tissue); hormonal (human hormones);

Reserve (spleen ferritin). The reserve or nutritional function of proteins is that proteins are used by the human body for the synthesis of proteins and biologically active protein-based compounds that regulate metabolic processes in the human body.

Proteins consist of b - amino acid residues connected by a peptide bond (- CO - NH -), which is formed due to the carboxyl group of the first amino acid and the b - amino group of the second amino acid.

There are several types of classification of proteins.

Classification according to the structure of the peptide chain: a helical shape in the form of a b-helix and a folded structure in the form of a c-helix are distinguished.

Classification according to the orientation of the protein molecule in space:

1. The primary structure is a connection of amino acids into the simplest linear chain using only peptide bonds.

2.Secondary structure is the spatial arrangement of the polypeptide chain in the form of an L-helix or B-fold structure. The structure is held together by the formation of hydrogen bonds between adjacent peptide bonds.

3. The tertiary structure is a specific arrangement of the b-helix in the form of globules. The structure is maintained due to the formation of bonds between side radicals of amino acids.

4. Quaternary structure is a combination of several globules that are in a state of tertiary structure into one enlarged structure that has new properties that are not characteristic of individual globules. The globules are held together due to the formation of hydrogen bonds.

Maintenance of the characteristic spatial tertiary structure of a protein molecule is carried out due to the interaction of side radicals of amino acids with each other with the formation of bonds: hydrogen, disulfide, electrostatic, hydrophobic. The configurations of the listed connections are shown in Figure 2.1.

Classification according to the degree of protein solubility.

Water-soluble proteins have a small molecular weight and are represented by egg albumin.

Salt-soluble proteins dissolve in a 10% sodium chloride solution; they are represented by globulins: milk protein casein, blood protein globulin.

Alkali-soluble proteins dissolve in 0.2% sodium hydroxyl solution; they are glutelins: wheat gluten protein.

Alcohol-soluble proteins dissolve in 60-80% alcohol; they are represented by prolamins: proteins of cereal crops.

Classification by protein structure.

Proteins, based on the structure of the protein molecule, are divided into simple or proteins and complex or proteids. Simple proteins include only amino acids, complex proteins include amino acids (apoprotein) and substances of non-protein nature (prosthetic group), which includes: phosphoric acid, carbohydrates, lipids, nucleic acids, etc.

Proteids are divided into subgroups depending on the composition of the non-protein part:

Lipoproteins consist of protein and lipid residues; they are part of cell membranes and the protoplasm of cells.

Glycoproteins consist of protein and high molecular weight carbohydrates and are part of egg whites.

Chromoproteins consist of protein and coloring substances - pigments containing metals, for example hemoglobin contains iron.

Nucleoproteins consist of proteins and nucleic acids and are part of the protoplasm of cells and the cell nucleus.

Phosphoproteins consist of protein and phosphoric acid and are part of the cell.

2.2 Non-enzymatic transformations of proteins

Proteins are used in food production not only as nutritional ingredients, they have specific properties - functional properties, which provide structure, influence the technology of food production.

Water binding capacity or hydration. Proteins are able to bind water, that is, they exhibit hydrophilic properties. At the same time, the proteins swell, their mass and volume increase. The hydrophilicity of gluten proteins is one of the characteristics characterizing the quality of grain and flour. The cytoplasm of a cell is a stabilized suspension of protein molecules. During the technological processing of raw materials, water is bound, and the products increase in volume - they swell.

Types of bonds in a protein molecule. Hydrogen: 1- between peptide groups; 2 - between the carboxyl group (aspartic and glutamic acids) and alcohol hydroxyl (serine); 3- between phenolic hydroxyl and imidazole. Electrostatic interaction: 4 - between base and acid (amino group of lysine and carboxyl group of aspartic and glutamic amino acids). Hydrophobic: 5 - with the participation of leucine, isoleucine, valine, alanine; 6 - with the participation of phenylalanine.

Denaturation of proteins is the process of changing the spatial structure of a protein under the influence of external factors: heating, mechanical action, chemical action, physical action, etc. During denaturation, the quaternary, tertiary, secondary structure of the protein disintegrates, but the primary structure is preserved and the chemical composition of the protein does not change . During denaturation, the physical properties of the protein change: solubility and water-binding capacity decrease, and the biological activity of the protein is lost. At the same time, the activity of certain chemical groups increases, and enzymatic hydrolysis of the protein is facilitated.

During technological processing of raw materials (cleaning, mixing, cooking, treatment with chemical reagents, using vacuum or high pressure), proteins are denatured, which increases the degree of their absorption.

Foaming. Proteins are capable of forming highly concentrated liquid - gas, solid - gas systems in the form of foam. Proteins serve as foaming agents in the confectionery industry (soufflés, marshmallows), in bread baking, and in beer production. The surface of gas bubbles is covered with a liquid or solid shell consisting of proteins. When this shell becomes thinner, gas bubbles burst, coalescence or fusion of bubbles occurs, and the foam becomes loose and less stable. The stability of the foam structure is an important factor in improving the quality of food products, including beer.

Melanoid formation (Maillard reaction). When the amino groups of proteins and amino acids interact with the carbonyl groups of carbohydrates, the reaction of melanoid formation occurs. This is a redox process with the formation of various intermediate products; the final reaction products, melanoidins, are brown in color and affect the color and taste of the finished products. The Maillard reaction occurs when drying malt, when boiling wort with hops, when baking bread, when cooking sugar syrups, when processing vegetables and fruits. The speed and depth of the melanoidin formation reaction depends on the composition of the product, the pH level of the environment (a slightly alkaline environment is more favorable), temperature, and humidity. Melanoidin formation reduces the activity of vitamins and enzymes, which leads to a decrease in the nutritional value of products.

2.3 Enzymatic hydrolysis of proteins

Protein hydrolysis is carried out by proteolytic enzymes. The wide variety of proteolytic enzymes is associated with the specificity of their effects on proteins. The site of application or action of a proteolytic enzyme is related to the structure of the radicals located near the peptide bond. Pepsin cleaves the bond between phenylalanine and tyrosine, glutamic acid and cystine (methionine, glycine), between valine and leucine. Trypsin breaks down the bond between arginine (lysine) and other amino acids. Chymotrypsin - between aromatic amino acids (tryptophan, tyrosine, phenylalanine) and methionine. Aminopeptidases act from the N-terminal amino acid side, carboxypeptidases from the C-terminal amino acid side. Endopeptidases destroy the protein inside the molecule, exopeptidases act from the end of the molecule. Complete hydrolysis of a protein molecule requires a set of a large number of different proteolytic enzymes.

2.4 Nutritional value of proteins

The biological value of proteins is determined by the balance of the amino acid composition in terms of the content of essential amino acids. This group includes amino acids that are not synthesized in the human body. Essential amino acids include the following amino acids: valine, leucine, isoleucine, phenylalanine, lysine, threonine, methionine, tryptophan. The amino acids arginine and histidine are partially replaceable, as they are slowly synthesized by the human body. The absence of one or more essential amino acids in food leads to disruption of the central nervous system. nervous system, stop the growth and development of the body, leading to incomplete absorption of other amino acids. The biological value of proteins is calculated by amino acid score (a.s.). The amino acid score is expressed as a percentage, representing the ratio of the content of an essential amino acid in the product protein under study to its amount in the reference protein. The amino acid composition of the reference protein is balanced and ideally meets every human need. essential amino acid. The amino acid with the lowest rate is called the first limiting amino acid. For example, in wheat protein, the limiting amino acid is lysine, in corn - methionine, in potatoes and legumes, methionine and cystine are limiting - these are sulfur-containing amino acids.

Animal and plant proteins differ in biological value. The amino acid composition of animal proteins is close to the amino acid composition of human proteins, therefore animal proteins are complete. Vegetable proteins contain low levels of lysine, tryptophan, threonine, methionine, and cystine.

The biological value of proteins is determined by the degree of their absorption in the human body. Animal proteins have a higher degree of digestibility than plant proteins. 90% of amino acids are absorbed from animal proteins in the intestines, and 60-80% from plant proteins. In descending order of protein absorption rate, foods are arranged in the following sequence: fish > dairy products > meat > bread > cereals

One of the reasons for the low digestibility of plant proteins is their interaction with polysaccharides, which impede the access of digestive enzymes to polypeptides.

If there is a lack of carbohydrates and lipids in food, the protein requirements change somewhat. Along with its biological role, protein begins to perform an energy function. When 1 gram of protein is absorbed, 4 kcal of energy is released. Excessive protein consumption poses a risk of lipid synthesis and obesity.

The daily protein requirement of an adult is 5 g per 1 kg of body weight or 70 - 100 g per day. The share of animal proteins should account for 55% and plant origin 45% of a person's daily diet.

3. Carbohydrates

3.1 Classification and structure of carbohydrates

Carbohydrates are polyoxyaldehydes and polyoxyketones, as well as compounds that turn into them after hydrolysis.

Carbohydrates are divided into three groups:

Monosaccharides;

Oligosaccharides or disaccharides;

Polysaccharides.

Monosaccharides usually contain five or six carbon atoms. The most common pentoses are arabinose, xylose, and ribose. The most common hexoses are glucose, fructose, and galactose.

Ribose is an essential component of biologically active molecules responsible for the transmission of hereditary information, the transfer of chemical energy necessary for the implementation of many biochemical reactions of a living organism, as it is part of ribonucleic acid (RNA), deoxyribonucleic acid (DNA), adenosine triphosphate (ATP) and etc. Arabinose and xylose are components of the hemicellulose polysaccharide. Glucose is included in the composition of fruits 2-8%, in the composition of polysaccharides: starch, glycogen, cellulose, hemicellulose, as well as in the composition of disaccharides: maltose, cellobiose, sucrose, lactose. Fructose is present in 2-8% of fruits and is a component of the disaccharide sucrose. Galactose is a component of the disaccharide lactose; galactose derivatives are part of the polysaccharide pectin.

Oligosaccharides are first-order polysaccharides, that is, they consist of 2-10 monosaccharide residues connected by glycosidic bonds. Of the oligosaccharides, disaccharides are the most common; dextrins, consisting of three, four or more glucose residues, are of practical importance in fermentation industries.

Disaccharides are divided into reducing and non-reducing disaccharides. Reducing compounds include disaccharides that have free hemiacetal hydroxyl, such as maltose, cellobiose, and lactose. Non-reducing disaccharides include those in which two hemiacetal hydroxyls are involved in the formation of the glycosidic bond; these are the disaccharides sucrose and trehalose.

Maltose contains b-D-glucopyranose linkage 1,4. Maltose is formed as an intermediate product of the hydrolysis of starch or glycogen.

The composition of cellobiose includes R-D-glucopyranose linkage 1,4. Cellobiose is part of the polysaccharide cellulose and is formed as an intermediate product of its hydrolysis.

The composition of lactose includes R-D-galactopyranose and b-D-glucopyranose bond 1,4. Lactose is found in milk and dairy products, often called milk sugar. In the figure, the formula for glucose is shown upside down.

The composition of sucrose includes I-D-fructofuranose and b-D-glucopyranose bond 1,2. Sucrose is part of a common food product - sugar. The hydrolysis of sucrose is carried out by the enzyme invertase or R-fructofuranosidase; the hydrolysis of sucrose produces fructose and glucose. This process is called sucrose inversion. Sucrose hydrolysis products improve the taste and aroma of products and prevent bread from becoming stale.

Trehalose contains a b-D-glucopyranose linkage 1,1. Trehalose is a component of fungal carbohydrates and is rarely found in plants.

Second-order polysaccharides consist of a large number of carbohydrate residues. According to their structure, polysaccharides can consist of monosaccharide units of one type - these are homopolysaccharides, as well as monomer units of two or more types - these are heteropilisaccharides. Polysaccharides can have a linear structure or a branched structure.

Starch consists of b-D-glucopyranose residues. The 1,4 bond is in the linear starch structure, which is called amylose, and the 1,4 and 1,6 bonds are in the branched starch structure, which is called amylopectin. Starch is the main carbohydrate component of human food. This is the main energy resource of a person.

Glycogen consists of b-D-glucopyranose residues, bonds 1,4 and 1.6, branches in glycogen are located every 3-4 glucose units. Glycogen is a reserve nutrient of a living cell. Glycogen hydrolysis is carried out by amylolytic enzymes.

Cellulose or fiber consists of R-D-glucopyranose residues, a 1,4 bond. Cellulose is a common plant polysaccharide; it is part of wood, the skeleton of stems and leaves, and the shell of grain crops, vegetables and fruits. Cellulose is not broken down by enzymes in the human gastrointestinal tract, so in human nutrition it plays the role of a ballast substance - dietary fiber, which helps cleanse the human intestines.

Pectic substances consist of galacturonic acid and methoxylated galacturonic acid residues connected by b - (1,4) - glycosidic bonds. There are three types of pectin substances:

Protopectin, or insoluble pectin, is bound to hemicellulose, cellulose or protein;

Soluble pectin has a high degree of esterification with methyl alcohol residues. Soluble pectin is capable of forming jelly and gels in an acidic environment and in the presence of sugar;

Pectic acids do not have methyl alcohol residues, while pectic acid loses the ability to form jelly and gels.

Pectin has a molecular weight of 20-30 thousand units, is not absorbed by the human body, and belongs to ballast carbohydrates (dietary fiber).

Hemicelluloses are heteropolysaccharides, since they contain R -D- glucopyranose, bond 1,4 (up to 70%) and 1,3 (up to 30%), R -D- xylopyranose, bond 1,4 and R -L- Arabofuronosis, relationship 1-2 and 1-3. Galactose and mannose residues are less common. The molecular weight of hemicelluloses is 60 thousand units. Hemicelluloses are included in cell membranes plants, including in the shells of the walls of starch grains, complicating the action of amylolytic enzymes on starch.

3.2 Conversions of mono and disaccharides

Respiration is an exothermic process of enzymatic oxidation of monosaccharides to water and carbon dioxide:

C6 H12 O6 + 6O2 > 6CO2 ^ + 6H2 O + 672 kcal

Breathing is the most important source of energy for humans. The breathing process requires a large amount of oxygen.

With a lack of oxygen or its absence, the process of fermentation of monosaccharides occurs. There are several types of fermentation in which various microorganisms take part.

Alcoholic fermentation is carried out with the participation of yeast enzymes according to the following scheme:

С6 Н12 О6 > 2СО2 ^ + 2С2 Н5 ОН+ 57 kcal

As a result of the alcoholic fermentation reaction, under the action of a complex of yeast enzymes, two molecules of ethyl alcohol and two molecules of carbon dioxide are formed. Monosaccharides are fermented by yeast at different rates. Glucose and fructose are most easily fermented; mannose is more difficult to ferment; galactose, the main carbohydrate in milk, is practically not fermented. Pentoses are not fermented by yeast. Along with the monosaccharides glucose and fructose, yeast can ferment the disaccharides maltose and sucrose, since yeast has enzymes that can decompose the molecules of these two disaccharides into glucose and fructose (b-glycosidase and b-fructofuranosidase). Alcoholic fermentation plays an important role in the production of beer, alcohol, wine, kvass, and in baking. Along with the main fermentation products - ethyl alcohol and carbon dioxide, during alcoholic fermentation by-products and secondary fermentation products are formed: glycerin, acetaldehyde, acetic acid, isoamyl and other higher alcohols. These products affect the organoleptic properties of products and often worsen their quality.

Lactic acid fermentation is carried out with the participation of enzymes from lactic acid bacteria:

C6 H12 O6 > 2CH3 ? CH (OH) ? COOH +52 kcal

As a result of the lactic acid fermentation reaction under the action of a complex of enzymes, two molecules of lactic acid are formed. Lactic acid fermentation plays an important role in the production of fermented milk products, kvass, and sauerkraut.

Butyric acid fermentation is carried out with the participation of enzymes of butyric acid bacteria:

С6Н12О6 > СН3 ? CH2? CH2? COOH + 2CO2 ^ +2 H2 ^

As a result of the reaction of butyric acid fermentation, a molecule of butyric acid is formed, two molecules of carbon dioxide and hydrogen. This process occurs at the bottom of swamps during the decomposition of plant debris, as well as when infection with butyric acid microorganisms occurs during food production.

Citric acid fermentation is carried out with the participation of enzymes from the mold fungus Aspergillus niger:

C6 H12 O6 + [O] > COOH? CH2? WITH? CH2? UNS

As a result of the citric acid fermentation reaction, a citric acid molecule is formed. This reaction is based on the process of producing citric acid.

Caramelization. The caramelization reaction is carried out by heating solutions of glucose, fructose, and sucrose above 100 °C. In this case, various transformations of carbohydrates occur. When sucrose is heated in a slightly acidic environment, partial hydrolysis (inversion) occurs to form glucose and fructose. When heated, three water molecules can be split off from glucose and fructose molecules, dehydration occurs with the formation of hydroxymethylfurfural, the further destruction of which leads to the destruction of the carbon skeleton and the formation of formic and levulinic acids. Hydroxymethylfurfural is formed by heating solutions of carbohydrates of low concentration - 10 - 30%; this substance has a brown color and a specific smell of baked bread crust.

In the first stage of the caramelization reaction, two water molecules are split off from the sucrose molecule. A caramelan is formed, consisting of anhydrous rings containing double bonds (dihydrofuran, cyclohexanolone and other compounds) in the ring, which are brown in color. At the second stage, three water molecules are split off and caramel is formed, which has a dark brown color. At the third stage, condensation of sucrose molecules occurs and caramel is formed, which has a dark brown color and is poorly soluble in water. Caramelization of sucrose is carried out at a sucrose content of 70 - 80%.

Melanoid formation or Maillard reaction. The reaction of the interaction of reducing disaccharides and monosaccharides with amino acids, peptides, proteins. As a result of the interaction of the carbonyl (aldehyde or ketone) group of carbohydrates and the amino group of proteins and amino acids, multi-stage transformations of reaction products occur with the formation of glucosamine, which undergoes rearrangement according to Amadori and Hates, then melanoidin pigments are formed, which have dark brown color, specific taste and smell. The melanoid formation reaction is the main cause of non-enzymatic browning of foods. This darkening occurs when baking bread, when drying malt, when boiling wort with hops in beer production, and when drying fruit. The reaction rate depends on the composition of the interacting products, pH of the environment, temperature, and humidity. As a result of the melanoid formation reaction, the content of carbohydrates and amino acids, including essential ones, is reduced by 25%, which leads to a change in the quality of the finished product and a decrease in its nutritional and energy value. There is evidence that the reaction products of melanoidin formation have antioxidant properties and reduce the absorption of proteins.

Scheme of the interaction of reducing disaccharides and monosaccharides with amino acids in a simplified form:

3.3 Enzymatic hydrolysis of polysaccharides

Starch hydrolysis is carried out by amylolytic enzymes. The enzyme b-amylase hydrolyzes starch, acting chaotically, breaking the 1,4 bond to form dextrins and a small amount of maltose. The enzyme b-amylase, acting on the starch grain, forms channels, splitting the polysaccharide into pieces. The scheme for starch hydrolysis is shown in Figure 3.1.

The enzyme β-amylase hydrolyzes starch, acting from the end of the chain, breaks the 1,4 bond and forms maltose; at the sites of amylopectin branching, the action of β-amylase stops, in this case a small amount of dextrins remains.

The enzyme glucoamylase acts from the end of the chain, cleaves off one molecule of glucose, breaks the 1,4 bond; at the sites of amylopectin branching, the action of glucoamylase stops and a small amount of non-hydrolyzed dextrins remains. The enzyme oligo-1,6-glycosidase cleaves the 1,6 bond to form dextrins. The enzyme isomaltase hydrolyzes the disaccharide isomaltose to glucose. Starch hydrolysis is the most important reaction that occurs during the technological processing of raw materials in the production of beer and alcohol.

Glycogen hydrolysis is carried out by amylolytic enzymes.

Pectin hydrolysis is carried out by pectolytic enzymes.

Soluble pectin changes from insoluble pectin to a soluble state under the action of the enzyme protopectinase or in the presence of dilute acids. In this case, pectin is cleaved from hemicellulose or other binding components. Soluble pectin is capable of forming jelly and gels in an acidic environment and in the presence of sugar;

Pectic acids are formed from soluble pectin under the action of the enzyme pectase (pectinesteresis) or in the presence of dilute alkalis, while pectic acid loses its ability to form jelly and gels. As a result of the action of the enzyme pectase, methyl alcohol is split off from soluble pectin. Enzymatic hydrolysis of pectin can be represented in the form of a diagram:

Hydrolysis of hemicelluloses is carried out by cytolytic enzymes, which include endo-R-glucanase, arabinosidase and xylanase. Hemicelluloses are not able to dissolve in water and significantly complicate the hydrolysis of starch. The action of the enzyme endo-R-glucanase cleaves off the glucose residue, the action of the enzyme arabinosidase cleaves off the arabinose residue, and the action of the enzyme xylonase cleaves off the xylose residue. With partial hydrolysis of hemicellulose, gum substances or amylans are formed, which have a lower molecular weight and dissolve in water, forming viscous solutions. The rate of starch hydrolysis during malt saccharification in beer production and the duration of mash filtration depend on the degree of hemicellulose hydrolysis.

3.4 Nutritional value of carbohydrates

One of essential functions low molecular weight carbohydrates give a sweet taste to foods. Table 3.1 shows the characteristics of the relative sweetness of various carbohydrates and sweeteners compared to sucrose, the sweetness of which is taken as 1 unit.

Carbohydrates are the main source of energy for humans; when 1 g of mono or disaccharide is absorbed, 4 kcal of energy is released. The daily human need for carbohydrates is 400 - 500 g, including mono and disaccharides 50 - 100 g. Ballast carbohydrates (dietary fiber) - cellulose and pectin substances must be consumed 10 - 15 g per day, they help cleanse the intestines and normalize its activity . An excess of carbohydrates in the diet leads to obesity, since carbohydrates are used to build fatty acids, and also leads to disruption of the nervous system and allergic reactions.

Table 3.1 Relative sweetness (RS) of carbohydrates and sweeteners

Carbohydrates		Carbohydrates or sweeteners
Sucrose		b-D-lactose
I-D-fructose		I-D-lactose
b-D-glucose
I-D-glucose
b-D-galactose
I-D-galactose		Cyclomat
b-D-mannose		Aspartame
I-D-mannose

4.1 Classification of lipids

Lipids are derivatives of fatty acids, alcohols, built using an ester bond. Lipids also contain ether bonds, phosphoester bonds, and glycosidic bonds. Lipids are a complex mixture of organic compounds with similar physicochemical properties.

Lipids are insoluble in water (hydrophobic), but highly soluble in organic solvents (gasoline, chloroform). There are lipids of plant origin and animal origin. In plants it accumulates in seeds and fruits, most of all in nuts (up to 60%). In animals, lipids are concentrated in subcutaneous, brain, and nervous tissues. Fish contains 10-20%, pork meat up to 33%, beef meat 10% lipids.

Based on their structure, lipids are divided into two groups:

Simple lipids

Complex lipids.

Simple lipids include complex (fat and oil) or simple (wax) esters of higher fatty acids and alcohols.

Complex lipids contain compounds containing atoms of nitrogen, sulfur, and phosphorus. This group includes phospholipids. They are represented by phosphotidic acid, which contains only phosphoric acid, which takes the place of one of the fatty acid residues, and phospholipids, which contain three nitrogenous bases. Nitrogenous bases add to the phosphoric acid residue of phosphatidic acid. Phosphotidylethanolamine contains the nitrogenous base ethanolamine HO - CH2 - CH2 - NH2. Phosphotidylcholine contains the nitrogenous base choline [HO- CH2 - (CH3)3 N] + (OH), this substance is called lecithin. Phosphotidylserine contains the amino acid serine HO-CH(NH2)-COOH.

Complex lipids contain carbohydrate residues - glycolipids, protein residues - lipoproteins, the alcohol sphingosine (instead of glycerol) contains sphingolipids.

Glycolipids perform structural functions, are part of cell membranes, and are part of the gluten of grains. The most common monosaccharides found in glycolipids are D-galactose and D-glucose.

Lipoproteins are part of cell membranes, in the protoplasm of cells, and affect metabolism.

Sphingolipids are involved in the activity of the central nervous system. When the metabolism and functioning of sphingolipids is disrupted, disturbances in the activity of the central nervous system develop.

The most common simple lipids are acylglycides. Acylglycerides include alcohol glycerol and high molecular weight fatty acids. Most common among fatty acids saturated acids(not containing multiple bonds) palmitic (C15H31COOH) and stearic (C17H35COOH) acids and unsaturated acids(containing multiple bonds): oleic with one double bond (C17 H33COOH), linoleic with two multiple bonds (C17 H31COOH), linolenic with three multiple bonds (C17 H29COOH). Among simple lipids, triacylglycerides (contain three identical or different fatty acid residues) are mainly found. However, simple lipids can be present in the form of diacylglycerides and monoacylglycerides.

Fats mainly contain saturated fatty acids. Fats have a solid consistency and elevated temperature melting. Contained mainly in lipids of animal origin. Oils contain mainly unsaturated fatty acids, have a liquid consistency and a low melting point. Contained in lipids of plant origin.

Waxes are esters that contain one high molecular weight monohydric alcohol with 18 to 30 carbon atoms and one high molecular weight fatty acid with 18 to 30 carbon atoms. Waxes are found in the plant world. Wax covers leaves and fruits with a very thin layer, protecting them from waterlogging, drying out, and exposure to microorganisms. The wax content is small and amounts to 0.01 - 0.2%.

Phospholipids are common among complex lipids. Phospholipids contain two types of substituents: hydrophilic and hydrophobic. Fatty acid radicals are hydrophobic, and phosphoric acid residues and nitrogenous bases are hydrophilic. Phospholipids are involved in the construction of cell membranes and regulate the flow of nutrients into the cell.

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