Introduction

Theoretical part

1 The nutritional value milk, importance in nutrition

2 Classification, characteristics of the range of milk

3 Quality requirements, defects

4 Packaging, labeling, storage of milk

Practical part

1 Assortment of milk sold by the Rublevsky store in Gomel. Suppliers

2 Quality of milk sold trading company

3 Packaging, labeling, transportation, storage conditions that ensure the quality of milk

Conclusions and offers

Literature

Applications

Introduction

Milk is a product of the secretory activity of the mammary gland of mammals. I.P. Pavlov called milk an amazing food prepared by nature itself. It contains in optimal proportions all the substances necessary for the normal development of the body: water, proteins, fats, milk sugar, mineral compounds, organic acids, vitamins, enzymes, hormones, gases and other components, of which there are more than 100. The digestibility of milk is 98-99%.

The natural purpose of milk is to feed babies who are not yet able to digest other foods.

The history of milk is as ancient as the history of mankind itself. Only having appeared on earth, a person immediately knew the taste of dairy products. Milk has been eaten for over 6,000 years. The most consumed type of milk is cow's milk.

Currently, milk is part of many products used by humans, and its production has become a large industry, new technologies have also appeared, a new range, so it is necessary to study this product in more depth.

The purpose of my course work is to study the nutritional value of milk, its importance in nutrition, the study of the classification and characteristics of the assortment of milk, quality requirements. And also to study all types of packaging, labeling and storage of milk.

The objectives of my term paper: to study the range of milk sold by a trading company; study and analyze the quality of milk sold by a trading enterprise; study the packaging, labeling, transportation conditions, storage, ensuring the quality of milk.

1. Theoretical part

.1 Nutritional value of milk, importance in nutrition

Milk- a biological fluid that is synthesized in the mammary glands of mammals from the constituent parts of the blood. The mammary glands are located in the tissues of the udder. The udder is divided into two parts. In each part there are two independent glands (anterior and posterior), not connected by ducts, which makes it possible to milk each of the parts of the udder separately.

Milk contains physiologically valuable nutrients that are well balanced, easily and completely absorbed by the human body.

Milk is an indispensable product of mass and everyday consumption, and also serves as a raw material for the production of butter, fermented milk products, cheeses, ice cream, canned milk.

A person per day should consume almost 1.5 liters of dairy products (in terms of milk), including 0.5 liters of milk, cow butter - 15-20 g, cheeses - 18 g, sour cream and cottage cheese 20 g each.

More than 120 chemicals have been found in milk, including: proteins, fats, minerals, vitamins, enzymes, etc. The energy value cow's milk is 2797 kJ. One liter of milk satisfies the daily requirement of an adult for fat, calcium and phosphorus, 53% for protein, 35% for vitamins - A, C, B1 (thiamine), 25% for energy.

The chemical composition of milk depends on the species and animals, the time of year, the conditions for feeding livestock, and other factors. Milk in its composition is a complex system consisting of organic and inorganic compounds. Organic substances: proteins, carbohydrates, fats, enzymes, vitamins. Inorganic: water, mineral salts, gases.

An important indicator of the chemical composition of milk is dry skimmed milk residue (SOMO), the content of which is used to judge the naturalness (undilutedness) of milk. The CMO is determined by subtracting the percentage of fat from the percentage of dry matter in milk.

Protein substancesare the most valuable component of milk, since the amino acids formed during their breakdown are a good plastic material for building body tissues. Milk protein is called casein.Casein is a complex protein phosphoprotein, in milk it is found in the form of a calcium salt, which determines its white color. Casein coagulates under the action of rennet and forms a dense clot used in the production of rennet cheeses and cottage cheese.

The simple proteins remaining in serum, albumin and globulin, are called whey, they do not precipitate under the action of rennet, they remain in the serum.

milk fat(average 3.8%) is in the form of fatty globules, covered with lecithin-protein shells. which prevent them from sticking. 1 ml of milk contains 3 billion fat globules with a diameter of 0.5 to 10 microns. When their shells are destroyed during processing and storage, free fat appears, which degrades the quality of the product. Milk fat is the best known dietary fat in terms of taste, composition, and digestibility. However, its shortcomings should also be noted. Milk fat is not resistant to high temperatures, light rays, atmospheric oxygen, water vapor, solutions of alkalis and acids. Under the influence of various factors, it is hydrolyzed, oxidized, salted, and as a result deteriorates.

Milk sugarIt has a useful property for humans, it penetrates the intestinal walls into the blood more slowly than others, stays in the intestine for a longer time and can be used to feed lactic acid bacteria, the development of which has a healing effect on the human body. When milk is heated to temperatures above 95°C its color varies from pale cream to brown.

milk sugar plays important role in the technology of production of fermented milk products and cheeses. From milk sugar in these products, in addition to lactic acid, carbon dioxide, alcohol, butyric acid and other compounds can be formed.

Mineralsare of great importance in the formation of new tissue cells, enzymes, vitamins, hormones, as well as in the mineral metabolism of the body. The content of mineral substances in milk is up to 1%. After burning milk, 0.7% ash is obtained. The composition of the ash includes salts of organic and inorganic acids, mainly phosphoric, citric and hydrochloric.

Among the mineral salts contained in milk, calcium and phosphorus salts occupy a special place. Calcium milk is highly absorbable and, in fact, is the main source of providing the body with this element. Calcium in milk is absorbed better than calcium in cereals, bread and vegetables. 1 liter of milk contains 1.2 g of calcium. Calcium is needed for bone formation, to regulate blood pressure reducing the risk of certain types of cancer.

Of the trace elements found in milk, manganese, copper, iron, cobalt, iodine, zinc, tin, vanadium, silver, etc. Manganese catalyzes oxidative processes in the cell and is necessary for the synthesis of vitamins C, B and D. Copper and iron are involved in hematopoiesis, iodine - in the synthesis of the thyroid hormone thyroxine.

Enzymescontained in milk such as: peroxidase, reductase, phosphatase, catalase, lipase, lactase.

Lipasesplits fat glycerides into fatty acids and glycerol, breaks down at temperatures of 75-80°C.

Phosphatasecauses hydrolysis of phosphoric acid esters, is destroyed at 75°С . By its presence in pasteurized milk, it is judged on the impurity of raw milk in it.

Peroxidasedecomposes hydrogen peroxide with the release of active oxygen, is destroyed at 80-82°C. The reaction to peroxidase checks the effectiveness of high pasteurization of milk.

catalasesplits hydrogen peroxide into water and molecular oxygen. There is a lot of it in the milk of animals with mastitis.

Reductase- a reducing enzyme accumulates in milk during the development of microflora, and its amount is used to judge the bacterial contamination of milk.

Lactasebreaks down lactose into glucose and galactose.

vitaminscan be: fat-soluble(A, D, E, K) and water soluble(B1, B2, B3, B6, B12, PP, C, H - biotin), folic acid.

Vitamin BUT(0.03 mg%) is formed in the body of the animal from feed carotene, is resistant to heat treatment, easily oxidized in the light and with air access.

Vitamin D(0.00005 mg%) is formed in the animal body from ergosterol under the influence of ultraviolet rays, resistant to heat treatment.

Vitamin E(0.15 mg%) resistant to high temperatures (up to 170°C), is an antioxidant for fats.

Vitamin With(2 mg%) is significantly destroyed during storage, transportation and pasteurization.

Vitamin IN 1(0.04 mg%) withstands heating up to 120°C in an acidic environment, less stable in a neutral and alkaline environment.

Vitamin IN 2(0.05 mg %) is destroyed in a weakly alkaline environment, stable in an acidic environment, when heated to 120 °C , collapses in the light.

Vitamin IN 3(0.38 mg%) resistant to heat, stimulates the development of bacteria.

vitamins AT 6(0.05 mg%) and AT 12(0.0004 mg%) are preserved during milk pasteurization.

Vitamin RRstable during the technological processing of milk.

Vitamin Hstimulates the activity of microorganisms, resistant to oxidation and heating.

Bactericidal substances- immune bodies (lysins, agglutins, antitoxins) have a detrimental or suppressive effect on microorganisms that have entered the milk. The time during which the bactericidal properties of milk are manifested is called bactericidal phase(or period). The bactericidal period lasts at 30°C for 3 hours, at 15°C - 12 hours, at 5°C - 36 hours. Foreign substances (pesticides, nitrites, etc.) can enter the milk, their content and control are regulated by standards.

Hormonessecrete endocrine glands. They are regulators of complex biochemical processes and communicate between individual organs. Under the influence of the hormones prolactin and thyroxine, lactic acid secretes milk.

Dyestuffs- carotene, chlorophyll, xanthophyll enter the milk from the feed.

Water- the main part of milk, the amount of water determines the physical state of the product, physico-chemical and biochemical processes in him.

Along with cow milk, milk of other farm animals is used in the national economy. The average chemical composition of the milk of various animals is given in Table 1.1.

The average chemical composition of the milk of various animals.

Table 1.1

Sheep milk -richer in fat and protein than cow's and is characterized by higher acidity and density. Fat globules are larger. It is not used as a drink due to the specific smell. It is used for the production of cheese and other types of pickled cheeses.

Goat milk -similar in composition to bovine, but contains more albumin. Fat globules goat milk smaller ones. Due to the lack of dyes, it is paler, but contains more vitamin C. It is used in a mixture with sheep for the production of cheeses.

Mare's milk -called albumin. It is a white liquid with a bluish tint of sweet taste, differs from cow's in an increased content of lactose, less fat, salts and proteins. When souring, mare's milk does not give a clot, casein falls out in the form of small, delicate flakes. Mare's milk has high bactericidal properties; in composition and properties, it differs little from that of women. It is used to make koumiss.

.2 Classification, characteristics of the assortment of milk

Cow's milkdepending on the heat treatment, it goes on sale pasteurized and sterilized.

-pasteurized fat content 1.5; 2.5; 3.2 and 6%;

-protein 1.0 and 2.5%;

-fortified (with vitamin C) - low-fat and fat content of 2.5 and 3.2%;

-milk with cocoa or coffee with a fat content of 1.0 and 3.2%;

-low-fat;

-baked milk with a fat content of 4 and 6%.

The following assortment of milk goes on sale: Volkovysk, Minsk; pasteurized cow Berestye, pasteurized Lung; pasteurized cow, enriched with bifidoflora, Rosinka; pasteurized Lugovoe; sterilized with lactulose; iodized Yodis; pasteurized, enriched with iodized protein; pasteurized Green Valley; fortified Vita; pasteurized Polesskoye, Molodetskoye, Vitalakt, etc.

For feeding infants, ion-exchange milk and vitalact-DM are produced.

ionic milkobtained by treating milk with a cation exchanger, while removing 20-25% of calcium, which is replaced by an equal amount of sodium and potassium; produced without additives, with vitamins of groups B and C.

Vitalact-DMproduced from a homogenized mixture consisting of normalized cow's milk, cream, refined sunflower oil, sugar and other additives.

sterilized milkreleased in paper bags with a polyethylene coating inside. Fat content - 3.2 and 3.5%.

For direct consumption, pasteurized or sterilized milk is used.

Wholecalled normalized or reconstituted milk with a certain fat content - 3.2% and 2.5%.

restoredrefers to milk prepared wholly or partly from canned milk. To obtain reconstituted milk, whole milk powder is dissolved in warm water and withstand at least 3-4 hours for the greatest swelling of proteins, elimination of watery taste, as well as to achieve normal density and viscosity. The mixture is then cleaned, homogenized, pasteurized, cooled and bottled.

High fat milkprepared from normalized milk with a content of 6% fat, subjected to homogenization.

meltedcalled milk with a content of 6% fat, subjected to homogenization, pasteurization at a temperature of at least 95 degrees and holding for 3-4 hours.

protein milkcontains an increased amount of dry fat-free substances. It is produced from milk, normalized in terms of fat content, with the addition of powdered or condensed milk.

fortified milkprepared from whole or non-fat milk enriched with vitamins A, C, D2.

low fat milkis the pasteurized portion of milk obtained by separation and containing not more than 0.05% fat.

Heat treatment of milk is necessary to kill microorganisms and destroy enzymes in order to obtain products that are hygienically safe and have a longer shelf life. For this, pasteurization and sterilization of milk are used.

Pasteurization can be long-term (at a temperature of 63°C, milk can withstand for 30 minutes), short-term (at a temperature of 72°C - for 15-30 seconds) and instant (high-temperature at 85°C and above without exposure). Heat treatment should preserve the nutritional and biological value of milk as much as possible, not lead to undesirable changes. physical and chemical properties milk. In the process of heating, whey proteins are denatured (structural changes in molecules), and the milk acquires the taste of a boiled product or the taste of pasteurization. As a result of pasteurization and sterilization, the amount of calcium in milk decreases due to the formation of poorly soluble calcium phosphate (precipitates in the form of a milk stone or burn along with denatured proteins). This impairs the ability of milk to rennet coagulation; in the production of cottage cheese and cheese, calcium chloride is added to pasteurized milk.

As a result of pasteurization and sterilization, the physicochemical and technological properties of milk change: viscosity, surface tension, acidity, the ability of milk to settle cream, the ability of casein to coagulate. Milk acquires specific taste, smell and color. The constituents of milk change. Milk is sent to the distribution network at a temperature not exceeding 8°C.

According to the standard, milk is classified as follows:

GOST 37-91. Butter cow. Specifications

GOST 1349-85. Canned milk.

GOST 3622-68. Milk and dairy products.

GOST 3623-73. Milk and dairy products. Methods for determining pasteurization

GOST 3624-92. Milk and dairy products. Titrimetric methods for determining acidity

GOST 3625-84. Milk and dairy products. Methods for determining density

GOST 4495-87. Whole milk powder.

GOST 5867-90. Milk and dairy products. Methods for determining fat

GOST 8218-89. Milk. Purity determination method

GOST 10970-87. Skimmed milk powder. Specifications

GOST 23327-98. Milk and dairy products.

GOST R 51917-2002. Dairy and milk-containing products.

GOST R 52054-2003. Natural cow's milk - raw material.

milk food assortment quality

1.3 Quality requirements, defects

The quality of milk is evaluated by organoleptic, physico-chemical and bacteriological indicators.

Milk must comply, in terms of organoleptic properties, with GOST No. 28283-89 “Drinking milk. Method for organoleptic evaluation of smell and taste, color and consistency.

By appearance and consistencymilk is a homogeneous liquid without sediment. Cream settling is not allowed in high-fat milk and baked milk.

Colourmilk should be white with a slightly yellowish tint, baked milk with a creamy tint, low-fat milk with a slightly bluish tint.

Vkuwith and smellmilk must be clean, free of foreign taste and smell not characteristic of fresh milk.

From physical and chemical indicatorsfor milk, the fat content, density, acidity, degree of purity, temperature, and the presence of phosphatase are normalized. The indicator of freshness is acidity. The acidity of pasteurized milk should be no more than 21°T, with the exception of high-fat milk (6%) - no more than 20°T and protein - no more than 25°T. The acidity of sterilized milk is not higher than 20°T, milk for baby food is not more than 19°T.

Density

The density of milk must be at least 1.024-1.030 g/cm 3depending on fat content.

From microbiological indicatorsthe total number of bacteria in 1 ml, the titer of Escherichia coli, pathogenic microorganisms are determined.

Milk defects

More Most of all, the quality of milk is reduced by defects in taste and smell.

Feed taste, smell of silage, barnyardand other odors are more often due to the adsorption of feed odors by milk.

Sour tasteoccurs when lactic acid bacteria develop in milk.

bitter tasteappears in milk during long-term storage in a chilled state as a result of the development of putrefactive microflora. Under the same conditions, a rancid taste may also appear, when, under the action of lipase, fat glycerides are split into glycerol and fatty acids.

metallic tasteoccurs in milk during storage when the metals of dishes with a broken half-day are dissolved.

Foreign tastes and odorsmilk is acquired during its transportation together with odorous products (onions, oil products, chemicals).

Salty and rancid flavorshas old milk due to a change in the mineral composition and an increased content of lipase.

1.4 Packaging, labeling, storage of milk sold in the Rublevsky store (produced by suppliers)

For milk packaging, mainly polymer-coated paper bags (tetra-pak, tetra-brik, pure-pak), plastic bags, flasks and other types of containers are used. Much depends on the shape of the package: the convenience of purchase for the buyer, the type of shipping container, the stability of the package during production and distribution. The sharper the corners in the packages (tetra-pack), the faster they are damaged, leak, which entails certain losses. For stacking tetra-packs, a special container has been developed and used - hexagonal boxes made of polyethylene low pressure. Milk in Pure-Pak and Tetra-Brick packages in blocks of 10-12 pieces is covered with shrink film and placed in container-equipment. Fin-pack - a soft polymer bag is also convenient for milk distribution. The use of these packages allows you to refuse the use of returnable glass containers. However, we must remember that all the polymer packaging in our country is not yet recycled and pollutes the environment. The following designations must be embossed or indelibly painted on the packaging of the container: the name or number of the manufacturer or trademark; type of milk volume in liters (on packages); date or day of the deadline for implementation; standard designation.

When pouring milk into flasks or tanks, a label is attached to the container or a label is hung with the same designations. Additional information for buyers is the application on the packages of information about the composition of the product, calorie content. Drawings and pointers for opening containers, conditions and periods of storage. Package labeling should be clear and colorful.

Keepmilk should be in clean and ventilated rooms without access to light. Pasteurized cow's milk should be stored at a temperature of 4 + -2 for no more than 5 days from the end of technological process, sterilized milk at a temperature of 0 to 10°C - 6 months, at a temperature of 0 to 20°C - no more than 4 months.

Relative humidity should not exceed 80%. At higher humidity in the room, mold can appear.

It is forbidden to store milk together with meat and fish products, vegetables, fruits and spices to avoid the appearance of foreign smell and pollution in it.

In refrigerating chambers and utility rooms, milk is stored on pallets and racks. Packaged dairy products are stored in the container in which they were delivered to the store.

At the workplace of the seller, milk is placed in refrigerated cabinets or refrigerated counters. In the absence of cooling means, the supply of milk taken out to the trading floor should be calculated for a two- or three-hour sales period.

2. Practical part

.1 Assortment of milk sold by the Rublevsky store (produced by suppliers)

I work in the Rublevsky store, located at 69, Cosmonauts Ave., owned by the Rublevsky Trade Open Joint Stock Company.

The type of this store is combined, since the forms of service in it are traditional, that is, through the counter, and self-service. This store specializes in food products, but it also has a “corner” with industrial goods.

The store operates on the basis of a license (Appendix A). The number of employees of this store is 56 people.

The total area of ​​the store is 1024.1 m 2, and the area of ​​the trading floor is 379.2 m 2

The turnover for the month is 605,000,000 million rubles, for the quarter - 1,815,000,000 million rubles, for the year - 7,260,000,000 million rubles.

The assortment of milk in this store is quite large, as the store works with many suppliers of dairy products. Milk is delivered to the store on time, it is very rare when suppliers delay delivery, and if this happens, then only for a good reason. This also applies to the quality of the supplied milk.

The range and suppliers of dairy products in the Republic of Belarus:

Table 2.1.1

Babushkina Krynka OAO Mogilev, st. Pavlova, d. 3.

№Product nameFat contentVolume, lRetail price, rub. past.2.4%11210film2Milk pet. past.3%11370film3Milk pet. pasty 1,5% 1940 film 4 Milk pet. past.3.2%11680lin-pak5Milk pit. past.2,5%11460lin-pak6Milk pit. fuel 4% 0.51010 lin-pak 7 Baby milk 3.2% 0.2620 tetra-brik

Table 2.1.2

TD Rumyantsevsky, Gomel, st. Br. Lizyukov, d. 1.

№Product nameFat contentVolume, lRetail price, rub. past.1.5%1950film2Milk pet. past.2.7%11300film3Milk pet. paste 3.6% 0.5820 film4 pasty 3.6% 11560 film

Table 2.1.4

SOZH OAO state farm-combine

№Product nameFat contentVolume, lRetail price, rub. pasty 3.5% 11540 film

Table 2.1.5

Savushkin product JSC, Brest, st. Ya. Kupala, 108.

№Product nameFat contentVolume, lRetail price, rub. paste3,1%12730pur-pak2Milk pet. paste2.6%12030film3Milk pet. paste1,8%11790film

Table 2.1.6

TD Dairy lace, Gomel, st. Br. Lizyukov, d. 1a

№Product nameFat contentVolume, lRetail price, rub. past.2.8%11330film2Milk pet. past.1.5%1950film3Milk pet. paste 3.2% 11450 film 4 paste 3.6% 11560 film 5 paste 2.8% 0.5760 film 6 past.3.2%0.5830pure-pak7Milk pit. past.3.2%11590pur-pak8Milk pit. paste 3.2% 11460 film 9 past.1.5%11010pur-pack

Table 2.1.7

Gormolzavod No. 1, Minsk, st. Soltysa, 185

№Product nameFat contentVolume, lRetail price, rub. past.1.8%11370tetra-brik3Milk pet. paste 3.2% 11450 film 4 fuel2.5%0.51030film5Milk pit. pasty 1.5% 1940 film

Based on a social survey, the milk of the Gomel supplier was recognized as the best milk. The reason for this is the taste and price of milk. The most purchased milk among the elderly is milk with a fat content of 1.5% in a plastic bag, as it is cheaper. And younger people pay less attention to the price and prefer milk with a higher fat content. Therefore, the milk of this supplier is ordered in larger quantities than the milk of others.

Renewability of the assortment of drinking milk for April 2011

Table 2.1.6

Product name Number of items Renewability % Drinking milk total including new items 4251

Conclusion: in April 2011, the assortment of milk in the store was updated by 4%.

Marking analysis

Consumer labeling of products must contain the following information:

product name: “Pasteurized milk “Mozyrskoe”;

mass fraction of fat: 2.7%;

name and location of the manufacturer: PUE "Mozyr dairy products", Belarus, 247760, Mozyr, st. Proletarskaya, 114;

trademark - available;

volume: 1000 l;

composition of the product: no, because not recombined;

nutritional value: proteins, fats, carbohydrates;

storage conditions: store at a temperature of 4±2 C;

-storage conditions and period of use of the sterilized product after opening the package: 2 days at a temperature of 4±2;

date of manufacture: 16.06.2011 at 16.06

designation of this standard: STB 1746-2007;

designation of the technological document in the presence of expiration dates different from those established by this standard:

information on confirmation of conformity (if any) - is absent, because milk is not long-term storage;

bar identification code - available;

Appendix E

Conclusion: Milk complies with the requirements of the STB 1746-2007 standard.

The certificate of quality and safety indicates:

certificate number and date of issue;

name and address of the supplier;

name and grade of the product;

lot number;

date and time (h, min) of shipment;

batch volume, l;

test results data (mass fraction of fat, density, acidity, purity, temperature at shipment);

the number and date of issue of the accompanying veterinary certificate (certificate) and the name of the organization of the state veterinary service that issued it;

designation of this standard.

Milk-based baby food labels must bear the inscription: “For baby food”. The font size of such an inscription cannot be less than the main font used.

On packages, adapted milk formulas and subsequent mixtures, a warning label “Breastfeeding is preferable for nutrition of young children” should be applied.

2.2 Quality of milk sold by the trader

Before milk enters the shelves of the refrigerator in the trading floor, it is tested for quality. Each batch of milk is accompanied by a copy of its quality certificate (Appendix B). Simultaneously with the verification of documents, the transport in which the milk was delivered is inspected. If milk is delivered to the store in a dirty vehicle, it will not be accepted. Transport delivering milk has a sanitary passport.

They also check the condition of the packaging and labeling during an external inspection of the entire batch of milk. After inspecting the container and checking the correctness of the marking, the batch of milk is accepted by quantity and its uniformity is established. In the case of mixing batches, the products are sorted into homogeneous batches.

When inspecting the container, pay attention to the presence or absence of leakage, determine by eye the completeness of pouring milk.

Upon detection of milk, which turned out to be with hidden defects, an act “Acceptance of goods by quality and quantity” is drawn up. Issued in 2 copies. One copy remains in the store, and the second is given to the supplier. In the future, milk is subject to exchange. Suppliers never refuse this and conscientiously fulfill all the conditions of the contract.

Drinking milk sold by this store corresponds in terms of good quality to GOST No. 28283-89 “Drinking milk. Method for organoleptic evaluation of smell and taste, color and consistency.

2.3 Packaging, storage, ensuring the quality of milk, labeling

Milk comes to this store already packaged and packaged. The packaging of milk is different, and since the assortment is large, the milk comes to the store in various packages.

The milk sold by this store comes in polymer-coated paper bags (tetra-pak, tetra-brik, pure-pak, lin-pak), plastic bags, flasks and other types of packaging. Much depends on the shape of the package: the convenience of purchase for the buyer, the type of shipping container, the stability of the package during production and distribution.

Milk entering this store has the following designations embossed or indelibly printed on the packaging:

1)mass fraction;

2)fat content;

)manufacturer, address;

)date of manufacture;

)expiration date;

)food and the energy value;

)compound;

)volume and barcode;

The store provides all the conditions for storing milk. It is stored in a special chamber where no light enters and there is constant ventilation of the room. The rules of the commodity neighborhood are also observed. Milk crates are placed on pallets. Store pasteurized at a temperature of 4 + -2 ° C for 5 days, sterilized from 0 to 10 ° C - 6 months, from 0 to 20 ° C - 4 months.

Conclusions and offers

Milk -biological fluid that is synthesized in the mammary glands of mammals from the constituent parts of the blood. Milk contains physiologically valuable nutrients that are well balanced, easily and completely absorbed by the human body.

The chemical composition of milk depends on the species and animals, the time of year, the conditions for feeding livestock, and other factors.

After analyzing the quality of milk sold by this store and having studied the suppliers, the range of milk, the following can be noted: when receiving milk, they evaluate not only the product, but also the container and vehicle on which this product was delivered. Transport must be sanitary transport, be clean, have all the conditions for transporting milk. Also, the representative of the supplier must have accompanying documents on the availability and quality of the product.

When comparing two samples of drinking milk, it turned out that milk, both during acceptance and during storage on the trading floor, did not change its organoleptic properties and complies with the requirements of the normative and technical document GOST No. 28283-89 “Drinking milk. Method for organoleptic evaluation of smell and taste, color and consistency.

When buying milk, each person makes a choice based on different indicators: price, taste, packaging, volume. Therefore, the assortment should be wide enough to satisfy different segments of the population.

Offers:

My suggestions for improving customer service: add a “new products” section to the trading floor, that is, put the received new products in this section. And also improve control over the trading floor, with the help of security guards.

Literature

1)Handbook of a commodity specialist food products- T.1 M .: Economics, 1987.

2)Mikulovich L.S. and others. “Commodity research of food products” - Minsk: BSEU, 1998.

)Mikulovich L.S. and others. “Commodity research of food products” - Mn .: Vysh. School, 2007.

)Kastornykh M.S., ed., Commodity research and examination of edible fats, milk and dairy products, M .: 2003.

)Shalygina E.A., General technology of milk and dairy products, M.: Kolos, 2001.

)Shepelev A.F. Commodity research and examination of milk and dairy products, Rostov, 2001.

Applications

Expiry date: 5 days

Date of the study: 05/18/2011.

Table 2.2.1

NameIndicators of the standardResearch resultsConclusionAppearance homogeneous liquid without sedimenthomogeneous liquid without sedimentmeets the requirements of the standardColorwhite with a slightly yellowish tintwhite, slightly with a yellowish tintmeets the requirements of the standardSmell and tasteclean, without extraneous flavors and odors not characteristic of fresh milk.pure, without foreign odors and tastes meets the requirements of the standardConsistency homogeneous, liquid without sediment .homogeneous, liquid without sediment. meets the requirements of the standard

Conclusion: pasteurized milk with 1.5% fat content in terms of quality, at the time of acceptance, meets the requirements of STB 1746-2007 “Drinking milk”.

Organoleptic assessment of the quality of drinking milk 1.5% fat

Product name: Pasteurized milk 1.5% fat

Date of manufacture: 18.05.2011

Expiry date: 5 days

Date of the study: 05/18/2011.

Table 2.2.2

NameIndicators of the standardResearch resultsConclusionAppearance homogeneous liquid without sedimenthomogeneous liquid without sedimentmeets the requirements of the standardColorwhite with a slightly yellowish tintwhite, slightly with a yellowish tintmeets the requirements of the standardConsistencyhomogeneous,liquid without sediment.homogeneous,liquid without sediment.complies with the requirements of the standardOdor and tasteclean, without extraneous taste and smell not characteristic of fresh milk .clean, without foreign odors and tastes meets the requirements of the standard

Conclusion: Drinking milk 1.5% fat did not change its organoleptic properties during storage. Complies with the requirements of STB 1746-2007 "Drinking milk".

The nutritional value of milk and products prepared on its basis determines its importance in children's and diet food. By including such foods in your diet, you will saturate the body with calcium and other valuable substances. Milk makes a person healthier and more beautiful.

What is nutritional value?

If you are interested in certain characteristics of products, you should know for sure what they mean. Yes, nutritional value is complete list properties that satisfy the physiological needs of the body. Most often, this concept means the content of proteins, fats and carbohydrates in every 100 grams of products.

It is also worth noting the importance of such an indicator as biological value. It characterizes the compliance of amino acid needs human body. Speaking of energy value, it is worth noting that this is the number of calories that are released during the processing of the product by the body.

Milk: chemical composition and nutritional value

Milk is the first human food, which gives the body everything it needs from birth. Due to the rich chemical composition, it is possible to maintain the active vital activity of the body. So, milk contains the following substances:

• proteins;
• fats;
• milk sugar;
• mineral salts;
• water.

It should be noted that this is a basic set of components that cannot fully characterize milk. The chemical composition and nutritional value can vary greatly, depending on the origin of the product, as well as the way it is processed.

If we consider in more detail the proteins contained in milk, they are represented by albumin, globulin and casein. The latter is involved in the formation of glycopolymacropeptide, which increases the absorption of other components. All proteins are characterized by easy absorption and contain all the amino acids necessary for the body.

Fats in milk are contained in the form of tiny particles. It is they who form everyone's favorite cream. Milk fat is 96% absorbed by the body, due to its high dispersion. Its content in the product depends on the season (summer this indicator decreases), as well as the quality of animal care.

Considering such an indicator as the nutritional, energy value of milk, one cannot fail to mention the carbohydrate component. It is represented by lactose. Precisely the presence this component due to the possibility of preparing fermented milk products.

The nutritional value of milk is determined by the high content of vitamins. The main ones are A and B. Ascorbic acid, nicotinic acid, riboflavin and thiamine are present in a small amount. The highest concentration of vitamins in milk is observed in the summer. Also, this indicator can be affected by the method of processing and storage conditions.

More about vitamins

As already mentioned, the nutritional value of milk and dairy products is largely due to the increased content of vitamins in them. So, if we take a closer look at the chemical composition, we can note the presence of the following useful components in it:

Different types of milk

The nutritional value of milk is largely determined by its origin. So, deer is considered the most nutritious. The concentration of proteins and fats reaches, respectively, 11% and 20%. As for the vitamin component, it is three times more saturated than in the case of cow's milk.

The nutritional value of milk is largely determined by the nature of the proteins that it contains. So, most farm animals (including cows and goats) give casein milk. And, for example, mare and donkey is albumin. Since it is most similar in composition to mother's milk, such milk is an ideal substitute for breastfeeding. Albumin particles are several times smaller than casein, and therefore we can talk about its good digestibility.

Whole milk

Despite the fact that milk is one of the most common products that has been known since childhood, not everyone thinks that there are several types that are characterized by certain indicators. So, for starters, you should pay attention to whole milk. The nutritional value, in this case, will be the highest, because the product has not been subjected to any processing. An exception may be the straining process, which is carried out immediately after milking.

Whole milk contains the highest amount of vitamins and minerals. There is also a high concentration of calcium, which is almost completely absorbed by the body. This product is credited with strengthening the immune system, normalizing the functioning of the nervous system, eliminating heartburn, accelerating metabolism.

However, there are a number of skeptical claims about whole milk. Given its high fat content, it is not suitable for feeding children. And in adulthood, not everyone tolerates this product well. So, according to the latest data, one sixth of the world's population suffers from lactose intolerance. Whole milk is an allergen, and can also cause dangerous infections.

Skimmed milk

The desire for harmony makes people buy products marked "0% fat". This trend has also affected milk. The amount of fat in it does not exceed 0.1%. In fact, this is the so-called reverse, which is obtained by separating cream from milk. It should be interesting to buyers that most of this milk is not sent to store shelves, but back to farms to feed animals.

Do not place high hopes on a product such as skimmed milk. Its nutritional value is negligible. Carbohydrates and proteins, respectively, 5% and 3%. Calorie content is characterized by an indicator of 35 kcal. At the same time, such milk is characterized by a rich vitamin and mineral composition. Nevertheless, doctors do not recommend using it on an ongoing basis.

It is worth paying attention to the manufacturing process. Nutritional value of dry skimmed milk significantly reduced during processing. When the fat component is removed, vitamins A and D are almost completely removed from the product. Thus, the proteins and calcium that remain in the milk are not absorbed by the body. With the frequent use of skimmed and powdered milk, the body's own resources are depleted.

Powdered milk: nutritional value

In a big city, it is not always possible to find a natural product. In addition, people tend to give known substances a more convenient form, such as powder. Powdered milk is a good example. The nutritional value of this product is the same as that of the original. But for this you need to prepare the so-called reconstituted milk. To do this, the powder is diluted in water (1: 7). At the same time, it is quite possible to cook from such milk homemade kefir, cottage cheese and other useful products.

The nutritional and biological value of milk is preserved thanks to a special manufacturing technology. Fast drying is carried out, and the temperature does not exceed 40 degrees. So everything useful material are saved. And due to the reduced moisture content (no more than 6%), it provides long-term storage product.

Nutritional value of condensed milk

It is worth admitting that few people are interested in such a question as nutritional value. For most people, this is a favorite delicacy. Nevertheless, condensed milk is not only tasty, but also a very useful product. To begin with, it is worth noting the high protein content in this product. Its concentration can reach 35%.

In fact, condensed milk is evaporated cow's milk. The nutritional value of the final product is slightly lower, but in general it is no less useful. Condensed milk is completely absorbed by the body, saturating it with calcium and phosphorus. Thus, by regularly consuming this product, you can strengthen the health of bones, eyes and enhance mental activity.

However, condensed milk should not be abused. The fact is that it contains a significant amount of sugar, which leads to a high calorie content (328 kcal) and a significant carbohydrate component (55.5 g). A large amount of the product contributes to the development of obesity, diabetes and caries.

Dairy products

The composition and nutritional value of milk make this product one of the most popular. However, in its pure form, few people love it. Most people prefer dairy products. They not only retain the benefits of milk, but also have a beneficial effect on the digestive system. So, you should especially pay attention to the following products:

• Kefir is made from pasteurized milk. A special leaven is added to it, after which the fermentation process begins. The nutritional value of this product depends entirely on the quality of the milk. If a whole product is used, then the protein component accounts for almost 3%, the fat concentration is 3%, and carbohydrates 4%.
• prepared from a pasteurized product using bacterial cultures. It will contain approximately equal amounts of fat and carbohydrates (about 3%) and 10% carbohydrates. Given the low acidity of the product, it is actively used in artificial feeding children.
• Belakt is also a fermented milk product produced using bacteria. It has a high content of enzymes. Another feature of the product is the presence in the composition of substances that, in their properties, resemble antibiotics.
• "Narine" is a fermented milk product that came to us from Armenia. There it is actively used for breastfeeding. Due to the special bacteria contained in the sourdough, the acidity index is quite low. And, getting into the body, "Narine" activates the production of a substance that suppresses pathogenic microbes. Proteins and fats in the product account for 3% and 4%, respectively, and carbohydrates - just over 6%.
• Koumiss is traditionally made from mare's milk. Nevertheless, recipes adapted for cow's are known. In milk, starter is added, which contains bacteria and yeast. The nutritional value largely depends on the quality of the base and the degree of maturity. It can contain up to 3% protein, up to 1% fat and 6% carbohydrates. The product is useful for digestion, and also has a tonic effect.
• Yogurt is not just a popular fermented milk product, but also a delicacy loved by everyone. In ancient times, it was prepared exclusively from To get yogurt, you need to add the so-called Bulgarian stick to the base. On average, the calorie content of the finished product is characterized by an indicator of 57 kcal. Proteins, fats and carbohydrates it contains, respectively, 4%, 2% and 6%. These figures may vary, depending on the type of milk and the method of processing. It is worth noting that only pure yogurt, which does not contain dyes and flavoring additives, has exceptional benefits.

Other popular products

Since ancient times, people have been interested in such a question as the nutritional value of milk. A great variety of dairy products are prepared on its basis. Nevertheless, there are a number of popular ones that are almost always present on the table, namely:

• Curd is one of the most valuable products nutrition, which is characterized by a high protein content (about 14%). Its preparation is based on processes. Curd is characterized by high acidity. But this indicator decreases with an increase in the level of fat content of the product.
• The process of making cheese is based on the precipitation of casein. Depending on how the milk is processed, the product can be hard, soft, brine or melted. The protein component can reach 30% (as well as fat).
• Sour cream is a product made from pasteurized cream. It is quite fatty (this figure can reach 40%).

Milk quality

The high nutritional value of milk proteins determines the popularity of this product. Nevertheless, only what is of high quality is useful for the body. The characteristics of milk largely depend on how the processing was carried out.

The milk that entered the plant is first of all checked by organoleptic index. If it turned out to be in accordance with the standards, it is carefully filtered to remove impurities. Next, the fat content is normalized by adding skim milk or cream.

The most important are the stages of pasteurization and sterilization. These processes are necessary for the destruction of pathogens, as well as a number of enzymes. Thus, it is possible to get safe product, which is characterized by long-term storage.

Pasteurization is carried out by prolonged heating. As a result, milk changes its natural taste. It is also worth noting the decrease in the concentration of calcium in the product.

Is milk dangerous for humans?

The nutritional and biological value of milk makes this product one of the most useful. Nevertheless, it is worth mentioning the danger that it carries. Milk can serve as a source of dangerous infectious diseases. In this case, viruses can get into the product from the animal and during processing.

Viruses can be found not only in milk, but also in products prepared on its basis. This increases the incubation period of the bacteria. So, the most dangerous diseases transmitted through milk are the following:

• Foot and mouth disease is a viral disease that affects the mucous membranes and respiratory tract. It appears in the form of blisters and ulcers. The virus of this disease is resistant to heat. To get rid of it, you need to boil the milk for at least 5 minutes.
• Brucellosis is a disease that affects almost all body systems. Its danger lies in the fact that at the initial stage it is almost asymptomatic. Milk from animals infected with brucellosis is subjected to prolonged boiling followed by pasteurization.
• Tuberculosis - affects mainly the respiratory system. If such an infection is found in an animal, then milk is strictly forbidden to be eaten.
• Other dangerous infections are anthrax, rabies, hepatitis, plague, and others. Animals with such diseases are subject to destruction with the obligatory presence of a sanitary doctor.

Conclusion

From the very first days of a person's life, it is milk that supplies the body with all the necessary nutrients and vitamins. Thus, the benefits of this product are undeniable. To maintain bones, digestive, nervous and other body systems in optimal condition, milk simply must be present in the diet. It is important to choose quality product, and whole or fat-free should be treated with caution.

Currently on the market there are wide range of dairy products, which are also characterized by high nutritional value. Among them, you can often find many copies marked "Farm" or "Rustic". Contrary to fashion trends, such products should be treated with extreme caution, because milk that has not been subjected to heat treatment and pasteurization may contain viruses that are dangerous to humans.

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INTRODUCTION

Of everything huge amount(about 150 items) of fermented milk products that have flooded our market, the undoubted leader is kefir - in the CIS it is about 2/3 of all dairy products.

This drink was not previously produced anywhere except the USSR. However, it would be a mistake to assume that the world has not appreciated great taste kefir - today it is made in many countries.

Before the First World War, some fermented milk products were generally unknown to Europeans, and this is recognized by the Europeans themselves. Doctors unanimously consider kefir one of the most useful products (from among fermented milk) that exist on the planet. It has already been proven theoretically and practically that kefir can not only normalize the microflora of the stomach and intestines, but also affect nervous system, and metabolism in the body, and significantly reduce the risk of cancer.

The birthplace of kefir is considered to be North Ossetia. In the Caucasus, there are many legends about the origin of kefir, more precisely, kefir sourdough. According to one version, the grains of kefir fungi were brought to the highlanders in his staff by the prophet Mohammed himself. One of the local names for kefir fungi literally translates as "millet of the prophet." However, it should be said that in the Caucasus the secret of making kefir was kept secret for centuries (almost like secrets good cheese in Europe, in the families of cheese makers, passed down from generation to generation).

So, the first official message about kefir was preserved in the text of the report in the Caucasian Medical Society of 1867, which spoke of healing benefits kefir. It is not surprising that the Caucasus used to be a health resort of the imperial court: the nobles constantly visited the mineral springs, so to speak, "went to the waters", about which information can be found even in the novels of M.Yu. Lermontov, who himself, by the way, "hired" an apartment literally at the foot of Mount Mashuk.

The All-Russian Society of Doctors at one time turned to the famous dairy farmer Balandin with a request to establish the production of kefir in Russia. So, despite the strictest prohibitions, Balandin's assistants managed to take 10 pounds of kefir grains to Russia, and this turned out to be enough to establish the production of kefir in Russia.

1. Characteristics of the group of fermented milk products

Products obtained from milk as a result of lactic acid fermentation (sometimes with the participation of alcoholic fermentation) are called fermented milk products.

There are dairy products:

Group 1 - products of simple (lactic acid fermentation) - fermented baked milk, various types of yogurt, acidophilus milk, cottage cheese, sour cream, yogurt,

2 - group - products of combined (lactic + alcoholic fermentation) - these are kefir, koumiss, etc.

Products of the 1st group have a fairly dense, uniform clot and a sour-milk taste due to the accumulation of lactic acid. Group 2 products have a sour-milk, refreshing, slightly stinging taste due to the presence of ethyl alcohol and carbon dioxide, and a gentle clot penetrated by the smallest bubbles of carbon dioxide. The clot of these products is easily broken when shaken, due to which the products acquire a uniform liquid consistency, which is why they are often called drinks.

In the production of fermented milk products, pure cultures of lactic acid bacteria are used. Depending on the products produced, the composition of pure cultures includes lactic acid streptococcus, bacillus bulgaricus, acidophilus bacillus, flavoring bacteria and lactic yeast. Each product is made using certain cultures of microorganisms.

The main biochemical processes that occur during the production of fermented milk products are as follows: lactic acid and alcoholic fermentation of milk sugar, casein coagulation and gelation; As a result of these processes, the texture, taste and smell of finished products are formed.

The properties of clots depend on the composition of milk and bacterial starter cultures, thermal and machining, method and duration of coagulation of milk proteins and other factors.

The digestibility of fermented milk products is higher than the digestibility of milk, since they affect the secretory activity of the stomach and intestines, as a result of which the glands of the digestive tract secrete enzymes more intensively, which speed up the digestion of food. With a pleasant, slightly refreshing and spicy taste, these products stimulate the appetite, thereby improving the general condition of the body. The medicinal properties of fermented milk products are based on the bactericidal activity of lactic acid bacteria and yeast in relation to pathogens of a number gastro- intestinal diseases, tuberculosis and other diseases. The dietary properties of fermented milk products are explained by the beneficial effect on the human body of a microorganism and substances formed during the fermentation of milk (lactic acid, alcohol, carbon dioxide, antibiotics and vitamins).

fermented milk kefir food raw materials

1.1 Chemical composition and nutritional value of fermented milk products

Microelements. These are valuable components of milk, necessary for the normal functioning of the body. They are part of enzymes, vitamins, activate or inhibit the activity of many of them. Some trace elements catalyze chemical reactions in milk and dairy products that lead to malformations. For example, excess copper in milk causes fat autoxidation and ascorbic acid oxidation, resulting in an oxidized taste in milk.

Vitamins. Milk contains all the vital vitamins, although some of them are present in enough. Vitamins are divided into two groups: fat-soluble (A, D, E) and water-soluble (C, PP, group B). There are functional differences between both groups of vitamins. So, fat-soluble vitamins exhibit a specific effect in the formation of tissues and cell groups; water-soluble B complexes are part of enzymes, including milk enzymes. Many vitamins are highly sensitive to high temperatures, light, acids, bases, and oxygen. Therefore, milk should be subjected to gentle processing in order to preserve the vitamins from destruction as much as possible.

Vitamins are of great importance for the body. They are part of the enzymes involved in protein, fat and other metabolism. Their deficiency leads to diseases - avitaminosis. Some vitamins affect the redox potential of milk, so they act as antioxidants; there are vitamins (carotene, B2) that give a certain color to milk and dairy products. Vitamin C prevents oxidative processes in milk and butter.

Minerals. The average content of these substances in milk is 0.7%, fluctuations can be in the range of 0.5 - 1%. Minerals are also found in milk in the form of salts of inorganic and organic acids in the molecular, colloidal and insoluble state. The most important are phosphoric and citric acid. O mineral composition milk is judged by the elements that remain in the ashes after burning it. This method is inaccurate, since organic compounds are destroyed during combustion, mineral salts are partially oxidized, partially volatilize. Therefore, in reality, there are more minerals in milk than the amount that is established by burning a sample of milk at a temperature of 550 - 600 ° C. Minerals are divided into macro- and microelements.

Milk sugar (lactose). It is found only in milk and dairy products. In cow's milk, on average, it contains 4.7% (fluctuations from 4.5 to 5.2%).

Depending on the end products of decomposition formed, different types fermentation.

Lactic acid fermentation is the most common. It is caused by enzymes of lactic acid bacteria. In the first stage, under the action of the enzyme lactase, milk sugar attaches a particle of water and breaks down into two hexoses: galactose and glucose. Further, pyruvic acid is formed from hexoses, which is reduced with the participation of lactic dehydrase to form lactic acid.

Lactic acid fermentation occurs under anaerobic conditions, but can also occur under aerobic conditions, because lactic acid bacteria are facultative. Lactic acid, accumulating in milk, causes protein coagulation and changes its properties. This fermentation underlies the production of fermented milk products and cheeses.

Propionic acid fermentation proceeds under the action of enzymes secreted by propionic acid bacteria. The products of this fermentation are propionic and acetic acids, carbon dioxide, water; it usually takes place during the maturation of Swiss, Soviet and other hard cheeses; observed after the appearance of lactic acid under the action of lactic acid bacteria.

Alcoholic fermentation together with lactic fermentation is used in the production of koumiss, ayran, kefir. As a result of fermentation, alcohol from 0.2 to 3% accumulates in products.

Butyric fermentation produces butyric acid, carbon dioxide, and hydrogen. Butyric fermentation in the production of dairy products is undesirable. In the presence of this fermentation, products deteriorate, they acquire an unpleasant taste and smell, cheeses and cans of milk cans swell. Butyric fermentation indicates unsanitary conditions for milk production and contamination with spore bacteria. These bacteria get into milk with particles of soil, manure, dust, feed, withstand pasteurization, and then, getting into normal conditions, begin to develop.

Sour-milk drinks have a characteristic taste and texture that meets the taste habits of the population. Them distinctive feature is the diversity of the microflora of starter cultures.

In accordance with the classification, fermented milk drinks can be conditionally divided into drinks prepared using multicomponent starter cultures of mesophilic lactic acid streptococci, thermophilic lactic acid bacteria and acidophilic bacilli, as well as drinks produced using thermophilic lactic acid bacteria. Lactic acid bacteria used in sourdough determine the main technological factors of production, as well as the taste and texture of the product.

Sour-milk drinks can be classified according to the main features, as follows:

according to physico-chemical parameters: fatty (6; 4; 3.2%); low-fat (2.5; 1.5; 1%); low-fat, with a normal or high content of milk protein;

by consistency: with a broken clot, with an undisturbed clot;

by types of lactic acid bacteria used for starter: prepared on multicomponent starter cultures (mesophilic lactic acid streptococci, thermophilic lactic acid bacteria, acidophilus bacilli) and on natural symbiotic starter culture;

according to the method of heat treatment: from pasteurized and baked milk;

according to the method of fermentation: developed by thermostatic (packed in small containers) and reservoir methods (in large containers).

1.2 Classification and range

Fermented milk products are products obtained from milk as a result of lactic acid fermentation (sometimes with the participation of alcoholic fermentation).

There are two groups of products:

Group 1 - products obtained as a result of only lactic acid fermentation - fermented baked milk, various types of yogurt, acidophilus milk, cottage cheese, sour cream, yogurt; have a fairly dense, homogeneous clot and a sour-milk taste due to the accumulation of lactic acid;

2nd group - products obtained by mixed lactic and alcoholic fermentation - kefir, koumiss, etc .; they have a sour-milk refreshing, slightly stinging taste due to the presence of ethyl alcohol and carbon dioxide, and a delicate clot, which is penetrated by the smallest bubbles of carbon dioxide, easily breaks when shaken, due to which the products acquire a uniform liquid consistency, which is why they are often called drinks.

The digestibility of fermented milk products is higher than that of milk, as they affect the secretory activity of the stomach and intestines, as a result of which the glands of the digestive tract secrete enzymes that accelerate the digestion of food more intensively. The dietary properties of fermented milk products are explained by the beneficial effect on the human body of microorganisms and substances formed during the fermentation of milk - lactic acid, alcohol, carbon dioxide, antibiotics and vitamins.

In the production of fermented milk products, pure cultures of lactic acid bacteria are used. Depending on the products produced, the composition of pure cultures includes lactic streptococcus (common yogurt), Bulgarian stick (Mechnikov yogurt, ryazhenka, varenets), acidophilus bacillus (acidophilic yogurt, acidophilus, acidalact, bifidok, bififrut), aroma-forming bacteria and lactic yeast (kefir mushrooms (kefir)). Each product is made using certain cultures of microorganisms.

Upon receipt of fermented milk products, the following main biochemical processes occur: lactic acid and alcoholic fermentation of milk sugar, casein coagulation and gelation; As a result of these processes, the texture, taste and smell of finished products are formed.

Coagulation of casein is caused by lactic acid formed during lactic fermentation of lactose (in the manufacture of cottage cheese by the acid-rennet method, lactic acid and the introduced rennet extract). When the pH of milk decreases, casein particles form aggregates and threads of a three-dimensional network of the milk clot, which captures the dispersion medium with fat globules and other components of milk (gelation). The properties of the clot depend on the composition of milk, the modes of thermal and mechanical treatment, the method and duration of coagulation of milk proteins, and other factors.

Fermented milk products are produced by thermostatic and reservoir methods.

With the thermostatic method, pasteurized milk is cooled to a temperature favorable for the development of sourdough microorganisms (for example, for yogurt 38--45 ° C), and cultures of lactic acid bacteria are introduced into it; fermented milk is bottled, which are corked and labelled. Milk bottles are placed in thermostats until a clot forms. After fermentation, the product is sent to a cold chamber, where it is kept for several hours for some compaction of the clot as a result of swelling of the protein (casein) and enhancement of the aroma due to the development of aroma-forming bacteria.

Products developed by the thermostatic method have an undisturbed dense clot.

With the tank method, which is more productive and economical, milk is fermented in large metal tanks. In the process of fermentation, it is continuously kneaded to destroy the clot, kept at low temperatures in the same containers; the resulting product is poured on automatic machines into bottles or paper bags.

The temperature regime and the duration of fermentation depend on the microflora that is part of the starter cultures. The end of fermentation is fixed by the strength of the clot and titratable acidity. For drinks, it is 75--85 °T, for sour cream 65-70 °T, for cottage cheese of various fat content 60-85 °T. The consistency, taste and smell of products are formed during this technological process. Lactic acid determines the consistency of the protein clot and gives a pleasant sour taste to the products. The accumulation of aromatic substances (volatile acids, acetaldehyde, diacetyl, adetoin, etc.) is the result of the vital activity of bacteria and yeast and depends on the composition of the bacterial starter and fermentation conditions. So, volatile acids (acetic, propionic, etc.) actively accumulate in kefir and cottage cheese, diacetonyl and acetoin - in kefir, sour cream, koumiss, acetaldehyde - in yogurt.

Due to the metabolic activity of starter cultures, antibiotic substances (nisin, benzoic acid, etc.) are formed that can retard the growth of pathogens of intestinal diseases, tubercle bacilli, etc. Starter culture microorganisms are able to synthesize vitamins C, group B, and some others, so fermented milk products contain more of these vitamins than in milk.

The composition of fermented milk products includes all the main nutrients, well balanced and easily digestible. These products have a number of additional useful consumer qualities - they accumulate carbon dioxide, lactic acid and other flavoring substances that stimulate appetite, stimulate the secretion of gastric juice, and improve metabolism. Live microorganisms are able to take root in the human intestine, suppressing putrefactive processes and preventing the formation of toxic products of protein breakdown.

Consumption of reduced-calorie dairy products helps to avoid excess weight and related diseases. Reducing the calorie content of dairy products is carried out by reducing or almost completely eliminating fat while maintaining or increasing the biological value of products by enriching them with vitamins (D, C, group B), calcium (adding milk powder, tricalcium phosphate, calcium gluconate).

A person should consume about 1.5 liters of dairy products per day (in terms of milk), including 0.5 liters of milk, cow butter 15-20 g, cheeses 18 g, sour cream and cottage cheese 20 g each.

Yogurt has several varieties, and their names depend on the heat treatment of milk (pasteurized or sterilized), the fat content in it and the composition of the bacterial starter used.

Yogurt mvchnikovskaya is obtained from pasteurized milk fermented with a culture of lactic acid streptococci with the addition of a culture of bulgarian sticks in a ratio of 4:1. Adding Bulgarian sticks to milk gives the product a more pronounced taste and delicate texture. Milk is fermented at a temperature of about 40--50 ° C, fermentation ends after 2.5--3 hours at a temperature of 38 ° C. The finished product has a pure sour-milk taste and smell, a moderately dense undisturbed stable clot, glossy on a break, without gas formation and whey release.

Yogurt ordinary is prepared from pasteurized milk by fermentation with starter from one culture of mesophilic lactic streptococcus (at a temperature of 32--35 ° C). It has a dense prickly clot, a refreshing slightly acidic taste. The duration of fermentation is 5-6 hours.

Southern curdled milk is made from pasteurized milk fermented with cultures of Bulgarian bacillus and thermophilic lactic streptococci in a ratio of 3:1 with or without the addition of lactose fermenting yeast. Fermentation temperature 50--55 °C. The Bulgarian stick is a strong acid-forming agent, therefore the southern curdled milk has a higher acidity (up to 140 °T). The finished product has a refreshing, pinching, sour taste, thick creamy, slightly viscous consistency.

Ukrainian curdled milk, or fermented baked milk, is produced from a mixture of milk and cream, normalized to a fat content of 6%, kept at a temperature of 95 ° C for 3-4 hours (stewed) and fermented with pure cultures of thermophilic races of lactic acid streptococcus. Ryazhenka is fermented at a temperature of 36--38 ° C for 2.5--3 hours. The finished product has a sour-milk pure taste (acidity 80--110 ° T) with a pronounced taste of pasteurization and a delicate clot without gas formation, the color of ryazhenka is cream with a brownish tinge. Ryazhenka is without additions and sweet. Depending on the mass fraction of fat, fermented baked milk is divided into: fat-free, low-fat, low-fat, classic, fatty, high-fat.

When enriched with biologically active substances and additives, fermented baked milk is divided into: fortified, enriched with microelements, enriched with macroelements, enriched with probiotics. When adding probiotic cultures of Bifidobactericum, the product is classified as bifidobacteria.

Yogurt acidophilus is prepared from milk fermented with pure cultures of lactic acid streptococci with the addition of acidophilus bacilli. For starter take 4.8% pure cultures of streptococcus and 0.5--2% acidophilus bacillus. In order for lactic acid streptococcus to develop simultaneously in milk, the fermentation temperature is set at 40--42 ° C. If, during fermentation, mucous races of acidophilus bacillus are introduced, then acidophilic yogurt has a slightly viscous clot. The acidity of curdled milk is 80-110 °T.

1.3 Raw materials used for the production of kefir

Requirements for the prepared milk.

According to GOST 13264-70, milk as a raw material for the production of high-quality dairy products is subject to requirements for physico-chemical, organoleptic and sanitary and veterinary indicators.

Milk should be natural, obtained from healthy cows, have a clean, pleasant, sweetish taste and smell characteristic of fresh milk; color from white to light cream, without any color spots and shades, uniform consistency, without protein clots and lumps of fat, without sediment, density not lower than 1027 kg/m3. Colostrum is not subject to acceptance in the first 7 days after calving and old milk 10-15 days before the start of the cow. Pronounced fodder flavors are not allowed in milk, especially onion, garlic, wormwood, which do not disappear even during technological processing. Milk with a persistent smell of chemicals and petroleum products, with the addition of neutralizing agents, with a residual content of chemicals protection of plants and animals, a musty aftertaste, a viscous consistency, which indicates the presence of putrefactive and foreign microflora in large quantities.

Compliance of milk with the standard in terms of physical and chemical parameters is established by analysis for the content of mass fraction of fat, titratable acidity, density and, if necessary, SOMO (by mass fraction of fat and density).

Calculations for delivered milk are made according to the basic fat content and protein content corresponding to the average norms for a given raw region.

Upon acceptance, milk is monitored for sanitary and microbiological condition by checking once a decade for mechanical contamination, peduntase or resazurin tests for bacterial contamination.

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term paper, added 07/04/2010


Importance of milk as a food product. Chemical composition and properties of milk. Thermophysical and optical properties, chemical composition and nutritional value of fermented milk products. Butter as a food product. The effect of milk on human health.

abstract, added 02/07/2013


Assortment of fermented milk drinks. Enrichment of fermented milk products with biologically active substances. Bacterial preparations for fermented dairy products. Dairy products functional purpose in human nutrition.

thesis, added 07/31/2013


Characteristics of the nutritional and biological value of basic foodstuffs. Biological hazards associated with food, genetically modified foods. Levels of impact of technogenic factors on the human body in the process of absorption of food.

control work, added 06/17/2010


Classification of vitamins on the basis of solubility. The chemical composition of milk intended for the production of butter. Products of lactic and alcoholic fermentation (yogurt; kefir, koumiss, acidophilic sour milk drinks, sour cream, cottage cheese).

Milk and dairy products are essential food products. They are the main products of dietary and clinical nutrition and differ from other food products in that they contain all the substances necessary for the body in an optimally balanced state. Milk provides normal growth, development and vital activity of the body. High nutritional, biological and medicinal properties milk has long been valued; in ancient times, milk was given such names as “juice of life”, “white blood”, “source of health”, etc.

The great Russian physiologist I.P. Pavlov viewed milk as amazing food prepared by nature itself and characterized by easy digestibility and nutritional value. The digestibility of milk and dairy products in the human body is 95-98%. The inclusion of dairy products in any diet increases its usefulness and quality indicators, contributes to better assimilation other components.

Physiological value(FC) - the ability of food components to activate the activity of the main body systems. FC is provided by physiologically active substances (PAS).

Depending on the effect on the human body physiologically active substances can be divided into the following groups:

1. PAS, which have a stimulating effect on the human nervous system. These include alkaloids: nicotine, caffeine, theobromine, as well as ethyl alcohol.

2. PAS affecting cardiovascular system. This group includes minerals, potassium, magnesium, calcium; vitamins B1, PP,

3. FAV, activating the digestive system. They include minerals: sodium, chlorine, enzymes, phospholipids, vitamins, fiber, hemicelluloses, pectin, aromatic substances, glycosides, nitrogenous and nitrogen-free extractives, hop resins and acids.

4. PAS that enhance the immune system. These include substances with a pronounced bactericidal and fungicidal action: polyphenols, dyes, aromatics, vitamins: B 1 , PP, glycosides, organic acids, among which benzoic, salicylic, gallic, citric, and lactic acids are distinguished by the greatest bactericidal activity.

5. PAS, which contribute to the removal of harmful substances from the body: toxins, toxic elements, bacterial etc. poisons. This group is represented by pectins, fiber, and some proteins.

It should be noted that harmful substances are considered to be of no value to the human body (for example, bacterial and fungal toxins), as well as beneficial substances that have negative impact on the human body in doses exceeding the MPC.

The above list of PAS related to different groups indicates that many food substances are multifunctional.

Nutraceutical components in milk favorably affect the human body: calcium, lactoferrin, lactoperoxidase, immunoglobulins, whey proteins, linolenic acid, oligosaccharides, phospholipids, etc.

There are many more nutraceutical components in colostrum, and some of them are present in much higher concentrations than in regular milk.

Milk and dairy products are extremely valuable and indispensable products in the prevention and treatment of diseases such as gastrointestinal, heart and blood vessels, liver, kidneys, diabetes, obesity, acute gastritis, etc. They should be consumed as part of a balanced diet to maintain tone and as a factor in increasing life expectancy.

Dairy products are of exceptional importance in the nutrition of children, especially in the initial period of their life, because. contains a significant amount of phospholipids, essential amino acids, normalizing the processes of growth and development of the body.

The physiological value of milk increases significantly when consumed in the form of fermented milk drinks. Their use contributes to the creation of an acidic environment in the intestinal tract and, as a result, the suppression of putrefactive microflora and the normalization of digestion. Therefore, dairy products are widely used as a remedy for intoxication of the body. poisonous products putrefactive microflora. Dairy products are digested much easier and faster than milk. In addition, they contain a large number of antibiotic substances with bactericidal action.

Milk (in the amount of 1 liter) satisfies the daily human need for animal fat, calcium, phosphorus; 53% - in animal protein; by 35% - in irreplaceable fatty acids ah and vitamins A, C, thiamine; 12.6% in phospholipids and 26% in energy.

Due to its unique chemical composition, dairy products can replace all other food products. The chemical composition of milk and dairy products is extremely diverse, and all of their components are essential in nutritional physiology.

Dairy products contain water, proteins, fats, carbohydrates, minerals, vitamins, organic acids, dyes, immune bodies, enzymes, gases, etc. Various factors influence the chemical composition: type of animal, age, conditions of feeding and keeping, period years, etc. (Table 2)

table 2

The chemical composition of cow's milk

Protein substances of dairy products. They are the most nutritionally valuable part of dairy products, they consist of casein and whey proteins - albumin and globulin. In addition to them, dairy products contain shell proteins of fat globules and some other little-studied protein substances, as well as nitrogenous compounds.

Squirrels dairy products have an extremely favorable quantitative and qualitative composition of amino acids, including all essential amino acids. Therefore, dairy proteins are considered complete. In addition, milk proteins, unlike other animal proteins, are relatively easy to reproduce and are recognized as the cheapest, which allows them to be used more and more every year as food additives to non-dairy products.

Milk protein surpasses the ideal protein in amino acid composition, which determines its high physiological value (see table 3).

Milk is a product of high biological value. Of the constituent parts of milk, of particular importance is:

A protein that is complete in terms of amino acid composition and has a high digestibility.

Milk fat contains biologically active fatty acids and is a good source of vitamins A and D.

Minerals in milk are represented by calcium, phosphorus, which are found in it in the form of organic salts that are easily absorbed by the body.

The high biological value of milk and dairy products makes them absolutely indispensable in the nutrition of children, the elderly and sick people.

Milk - perishable product, which is a good breeding ground for the development of pathogens of various diseases.

Chemical composition and nutritional value of cow's milk

The chemical composition of milk depends on

animal breeds,

lactation period,

The nature of the feed

Milking method.

The chemical composition of milk: proteins - 3.2%, fats - 3.4%, lactose - 4.6%, mineral salts - 0.75%, water - 87-89%, dry residue - 11 - 17%.

Milk proteins have a high biological value. Their digestibility is 96.0%. Essential amino acids are contained in sufficient quantities and optimal ratios. Milk proteins include: casein, milk albumin, milk globulin, fat globule shell proteins.

Casein accounts for 81% of all milk protein. Casein belongs to the group of phosphoproteins and is a mixture of its three forms - a, p and y, which differ in the content of phosphorus, calcium, and sulfur.

Milk albumin has a high content of sulfur-containing amino acids. The content of albumin in milk is 0.4%. Milk albumin contains a lot of tryptophan. Milk globulins are identical to blood plasma proteins and determine the immune properties of milk. Milk globulins make up 0.15%, immune globulins - 0.05%. The protein of the shells of fat globules is a lecithin-protein compound.

milk fat in milk is in the form of the smallest fatty globules and is represented by 20 fatty acids, mainly low molecular weight - butyric, caproic, caprylic, etc. Polyunsaturated fatty acids in milk, in comparison with vegetable oil, few. light, oxygen, heat cause salting and rancidity of milk fat. Milk contains phosphatides - lecithin and cephalin. Of the sterols, milk contains cholesterol, ergosterol.

carbohydrates in milk are lactose, which, when hydrolyzed, breaks down into glucose and galactose. Lactose tastes less sweet (5 times) than beet sugar. Caramelization of lactose occurs at 170 - 180°C.

Minerals. Milk contains calcium, phosphorus, potassium, sodium in the form of easily digestible organic salts.

It should be noted the high content of calcium salts and its good ratio with phosphorus (1:0.8).

Of the trace elements in milk contains: cobalt - 0.3 mg / l, copper - 0.08 mg / l, zinc - 0.5 mg / l, as well as aluminum, chromium, helium, tin, rubidium, titanium.

Vitamins. With milk, a person receives vitamins A and D, as well as some amounts of thiamine, riboflavin. The content of vitamin A in milk is subject to seasonal fluctuations. In fermented milk products, the content of thiamine and riboflavin increases by 20-30% due to their synthesis by lactic acid microflora.

Milk contains many enzymes, included in its composition and produced by the microflora present in it. The level of individual enzymes is used to assess the degree of bacterial contamination of milk. For example, reductase is used to assess the degree of bacterial contamination of raw milk, phosphatase and peroxidase - to check the effectiveness of milk pasteurization.

Sanitary and epidemiological significance of milk. The role of milk in the occurrence of intestinal infections, food poisoning of a bacterial nature, measures for their prevention. Animal diseases transmitted through milk and sanitary assessment of milk obtained from farms that are unfavorable for tuberculosis, brucellosis, foot-and-mouth disease and other animal diseases.

Milk is an excellent nutrient medium for the development and reproduction of most types of microorganisms. Diseases transmitted through milk can be divided into two groups:

1) animal diseases

2) human diseases.

Animal diseases transmitted to humans through milk

The main diseases transmitted to humans through milk are

Tuberculosis,

Brucellosis,

coccal infections.

Brucellosis called Br. melitensis, Br. abortus bovis, Br. abortus suis.

Brucellosis affects cows, sheep, goats, deer; from pets cats and dogs.

2 forms of the disease:

Professional form on contact

Brucella are resistant to environment and are well preserved in milk and dairy products.

Sick animals are brought to separate brucellosis farms, the milk obtained from such animals is neutralized by heating, boiling for 5 minutes and used for household needs within the farm - for feeding calves.

Milk of animals that react positively to brucellosis, but without clinical signs of the disease, is allowed to be eaten after preliminary reliable pasteurization (30 min at 70 ° C); Pasteurization of such milk must be carried out on the farm. At dairies, milk coming from farms that are unfavorable for brucellosis is pasteurized again. Due to the special danger of Br. melitensis milking sheep with clinical signs of brucellosis is prohibited.

To prevent brucellosis, it is necessary once a year for the entire livestock to produce serological (Wright and Heddelson) or allergic (Burne) reactions to identify diseased livestock. This is part of the tasks of veterinary workers who monitor the condition of animals.

Tuberculosis It is caused by tubercle bacilli of three types: human, bovine, avian. The largest number tubercle bacilli enters milk with udder tuberculosis of animals, as well as generalized and miliary forms of tuberculosis. Tuberculosis sticks remain viable in milk for 10 days, dairy products - 20 days, butter in the cold - 10 months, cheeses - 260-360 days. Milk from cows with tuberculosis is to be destroyed, and from cows that react positively, but do not have a clinical picture of tuberculosis, it is allowed to use it in nutrition after thorough pasteurization at a temperature of 85 ° C for 30 minutes.

Pasteurization must be carried out at the place of receipt of milk.

To prevent transmission through milk of tuberculosis from a person, it is necessary:

1) annual examination of employees of farms and dairy enterprises for tuberculosis;

2) removal from work of patients with an active form of tuberculosis;

anthrax caused by bacillus B. anthracis, which can be excreted in milk. The microbe itself is unstable and quickly dies in the environment, but is able to form stable spore forms. Milk from cows with anthrax must be destroyed under the supervision of a veterinarian. Preliminary neutralization of milk is carried out by adding 20% ​​chlorine-lime milk, boiling for 2-3 hours, adding 10% alkali and further heat treatment at a temperature of 60-70 ° C.

For the prevention of anthrax, active immunization of animals with a live attenuated Tsenkovsky vaccine or a live vaccine from an avirulent strain is used. The milk of vaccinated animals with the Tsenkovsky vaccine must be boiled for 5 minutes for 15 days. When using the STI vaccine, milk is used without restrictions; when the animal's temperature rises, the milk must be boiled.

Q fever, or pneumorickettsiosis, is caused by Burnet's rickettsia. Burnet's rickettsiae are excreted by animals in urine, milk, feces and fetal membranes. They are resistant to chemical and physical factors, they remain viable when heated for an hour at 90 ° C. In lactic acid products they remain viable for 30 days, butter and cheese - 90 days. Rickettsia Burnet is the most persistent of all other non-spore pathogens. Milk from animals with Q fever must be destroyed. Persons caring for sick animals must follow the instructions for caring for sick animals.

foot and mouth disease caused by a virus. Contained in saliva, urine, feces, milk of sick animals. The consumption of raw milk from sick animals is the cause of human disease. In the environment, the foot and mouth disease virus is stable, remains viable for 2 weeks, in feed - 4 months. It is very sensitive to the effects of physical and chemical factors. At 80-100 °C it dies instantly, it also dies quickly at pH 6.0-6.5. Quarantine is imposed on dysfunctional farms for foot and mouth disease and the export of milk is prohibited. Milk from sick animals must be boiled for 5 minutes. Such milk does not contain the virus and can be used on the farm. The ban on the export of milk is associated with the risk of the spread of foot-and-mouth disease to nearby areas. In some cases, when boiled milk and cream cannot be used on the farm, delivery to factories may be allowed under strict veterinary and sanitary supervision over the processing of exported containers.

Mastitis. Milk-borne food poisoning is mainly due to diseases of staphylococcal etiology. The main cause of staphylococci entering milk is mastitis in dairy cattle. With mastitis, milk is salty in taste and has an alkaline reaction. In milk, physical and chemical parameters change. Enterotoxin, which is formed in milk, withstands heating up to 120 ° C, is preserved in pasteurized milk, products that have undergone heat treatment.