Fundamentals of food technology study manual

CHAPTER I. RAW MATERIALS AND SCIENTIFIC BASIS OF FOOD 
TECHNOLOGY 
1. Types of raw materials for food production 
2. Food industry enterprises are divided into two large groups according 
to the type of processed products: 
3. Enterprises processing plant raw materials. 
4. Enterprises processing animal raw materials. 
Plant raw material processing enterprises are divided into raw material 
primary processing and raw material secondary processing industries. Primary 
processing enterprises of raw materials can include flour and cereal, powdered 
sugar, canning, primary winemaking, primary preparation of alcohol, tobacco and 
tea leaves, vegetable oil production enterprises. Their raw materials are grain, fruit 
and vegetable crops, oilseeds, etc. Enterprises of secondary processing of raw 
materials include bread, pasta, confectionery, white sugar, secondary winemaking, 
tea and cigarette production, oil processing enterprises (margarine, mayonnaise, 
soap). The raw materials of these enterprises are products of primary processing 
enterprises: flour, sugar, vegetable oil, wine materials, etc. 
The more types of food industry products there are, the more diverse the raw 
materials are. Therefore, they can be divided into certain groups according to their 
main characteristics or chemical composition. For example, it can be divided into 
groups of dry vegetable raw materials and wet vegetable raw materials, or into 
groups of carbohydrate raw materials, oily raw materials, protein raw materials, 
and essential oil raw materials. 
Any raw material is a biomaterial, its specific properties are determined by 
indicators such as chemical composition, elements of cell and tissue structure. The 
chemical composition of these raw materials includes proteins, carbohydrates, 
lipids, vitamins, enzymes and trace elements. 
The quality of raw materials belonging to each group is measured and 
determined by specific parameters. These quantities are divided into groups of 
quantities indicating physical, chemical, technological, organoleptic and other 
properties of raw materials. In particular, grain quality indicators are divided into 
five groups: botanical-physiological indicators - plant type, variety, germination 
period and amount, germination energy; organoleptic indicators - color, taste, 
smell; physical indicators - shape and size, absolute and natural weight, etc.; 
mechanical parameters - tensile modulus, dispersibility, viscosity, etc.; chemical 
indicators - moisture content, ash content, gluten content, acidity, etc.; 
technological indicators - grain flour production, 
Fruit raw materials are divided into 4 groups according to their structure and 
production on the plant stem: seeds (apples, pears, citrus fruits), grains (cherries, 
cherries, plums, apricots), soft fruits ( grapes, currants, raspberries) and nuts 
(almonds, walnuts, pistachios). 
Raw materials are divided into 2 groups: vegetative - leaves, roots and stems 
(cabbage, lettuce, radish, onion, carrot, potato, beet, etc.) and fruits (zucchini, 
cucumber, tomato, peas, etc.). 

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Storage of raw materials is an organizational part of any technological 
process, the task of which is to store raw materials without loss or with minimal 
seed and to maintain or increase the quality of raw materials.The types of methods 
used in practice to solve the problem of storage of raw materials are: 
1. Preparation of raw materials for storage (cleaning from impurities, sorting, 
combing or storage, etc.). 
2. Drying of raw materials (grains and oilseeds) or canning (fruits and 
vegetables). 
3. Creation and automatic management of optimal conditions in the 
environment (composition, relative humidity, temperature). 
4. Preventing the entry of various pests and insects (insects, rodents, birds). 
5. Preparation of raw materials for production. 
The implementation of these storage measures not only preserves the 
quantity of raw materials, but also preserves its technological quality and lays the 
foundation for the production of quality food products. 
There are losses in the storage of raw materials until the processing period. 
These losses are of two types - loss in mass (decreased in weight) and loss in 
quality (decreased in desirable content). Although these losses are interrelated, 
mass loss does not always affect quality (spill reduction). Storage losses of raw 
materials can be divided into five groups: mechanical, physicochemical, biological, 
biochemical and chemical losses. Mechanical losses are mainly due to spillage, 
scattering, washing according to the physical properties of raw materials. 
Physico-chemical losses of raw material are mainly due to evaporation and 
drying. Such losses are mainly characteristic of liquid products, fruits and 
vegetables. 
The main two causes of biological loss of raw materials are microbiological 
processes and the increase of pests (insects and rodents). 
Biochemical losses occur in raw materials due to the continuation of the 
respiration process characteristic of a living organism. 
Chemical losses occur due to reactions that can be carried out under the 
influence of radiation, light, air oxygen, various inorganic catalysts. 
Prevention of the above-mentioned losses is the main task of storage of raw 
materials. The principle of organizing storage is chosen depending on whether the 
raw materials are dry (grain, flour, etc.) or wet (fruits and vegetables). 
Despite the fact that grains and grain products are very different, their storage 
properties are similar. When the humidity in their storage exceeds the critical limit, 
the rate of biochemical and microbiological processes increases dramatically. 
Because it is natural for every gram of grain and grain products to contain 
hundreds of thousands of microorganisms. The optimal temperature for their 
development is 20-40 
0
С. Therefore, if the temperature is kept at the level of 8-10 0 
С, the development of microorganisms is stopped. 
Types of water raw materials are more and more diverse than grain products. 
Despite the difference in their botanical type, variety, fruit or vegetable 
characteristics, quality level, the principles of storage conditions, storage 
preparation and storage are similar. Because the uniqueness of this group of raw 

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materials is that they contain a lot of moisture. One-fifth of this moisture is in the 
bound state, and the rest is in the free state. Therefore, they are very sensitive to 
metabolic processes and environmental conditions. These raw materials are stored 
at low temperatures and high relative humidity to prevent the loss of moisture in 
order to slow down the metabolism and microbiological processes as much as 
possible. Loss of moisture leads to fruit wilting and weight loss, It also causes 
decay and mold due to the decrease in immunity. Vegetables and fruits are also a 
favorable habitat for microorganisms. For example, 1-2 million per gram of outer 
skin layers of cabbage or potato. will be a microorganism. The resistance of 
aqueous raw materials to microorganisms depends on their chemical composition, 
natural properties and external environmental conditions. Maintaining the natural 
durability of raw materials is the main task of the preservation process. depends on 
natural features and external environmental conditions. Maintaining the natural 
durability of raw materials is the main task of the preservation process. depends on 
natural features and external environmental conditions. Maintaining the natural 
durability of raw materials is the main task of the preservation process. 
During the growth of plants, the processes of synthesis of useful substances 
are mainly carried out in their leaves, stems, seeds and fruits, while in the storage 
of agricultural products mainly hydrolytic - decomposition processes take place. 
However, after harvesting, the raw material undergoes a post-harvest ripening 
phase, in which the synthesis processes of the growth period come to an end. 
During the subsequent storage period, the raw material gradually undergoes the 
processes of the dormant stage from the post-harvest ripening stage. In such a 
natural state of rest, physiological processes are minimal and germination is not 
observed. However, in the process of respiration, oxidation-reduction reactions 
take place with the participation of enzymes, raw materials emit heat and carbon 
dioxide, toxins are broken down, and the immunity of raw materials increases. In 
this case, the consumption of raw material is extremely low. The main factor in 
maintaining this condition is low temperature. The deterioration of the quality of 
raw materials, which has lost its peaceful state, accelerates. Depending on the type 
of raw materials, it undergoes biochemical and chemical processes of self-heating, 
physiological nausea and, at the last stage, germination, and becomes completely 
useless. 
Raw material storage regimes are temperature, relative humidity and gas 
content of the environment. For example, there are three modes of storage of grain 
mass: dry state (up to critical moisture); in a cooled state; under oxygen-free 
conditions. In such regimes, it is possible to store grain for 3-4 months in 
enterprises, 2-3 years in silo elevators, and 4-5 years in special warehouses. 
Fruits and vegetables can be stored in a chilled state in two ways: chilled and 
frozen. The main condition for good storage of any fruit and vegetable is the 
optimally selected cooling temperature and relative humidity. For example, apples 
-0.5 to +0.5 
0
С; grains 0 
0
С; tangerine at temperatures from 0.3 to 2 
0
С and relative 
humidity of 80-85% for legumes; 85-90% for apples, grapes, pears; 78-83% is the 
optimal condition for citrus. Potatoes should not be cooled to temperatures below 0 
0 С. There are no universal storage conditions for fruits and vegetables. The shelf 

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life of any fruit and vegetable, even under optimal conditions, is its individual 
characteristic and has a certain limit. If fruits and vegetables such as apples, 
grapes, cabbage, some varieties of onions are stored for 6-7 months, tomatoes, 
cucumbers, 
The methods of preparing raw materials for processing are different, and 
which method to use depends on the type of raw materials, their physical 
condition, and the method of further processing. In this case, if the methods of 
preparation for processing of various dry-scattering raw materials are similar, the 
methods of preparation for processing of various aqueous raw materials will also 
be similar. 
Scientific basis of handling and processing of food raw materials 
Physico-chemical basis of food technologies.
Food technology studies the processing methods of converting raw materials 
into products. It is based on the laws of physics, chemistry, biology and other 
sciences, because any technological process is a complex of physical, chemical and 
other effects on raw materials. 
Food technological processes are very diverse, as are the types of products. 
Classification or grouping of technological processes is based on the similarity of 
the raw material processing method. Therefore, based on the generality of 
processing methods, they can be conditionally divided into four groups: Group I - 
productions based on hardening, Group II - physical-chemical productions, Group 
III - mechanical-thermophysical productions, Group IV - chemical productions. 
I. The main process in production based on tanning is tanning. Fermentation 
is used in the production of bread and bakery yeast, in beer, grape wine, alcohol 
production enterprises, etc. 
The specialty of this group of companies is the use of carbohydrate-digesting 
microorganisms in their technologies. The life activity of microorganisms ensures 
the progress of a certain technological process. Microorganisms, in turn, get energy 
to live from the oxidation of organic matter. Microorganisms can live in an aerobic 
(oxygen) or anaerobic (no oxygen) environment. In various technological 
processes, the characteristics of microorganisms living in these two conditions are 
used. 
Under the conditions of aerobic respiration, microbiological products 
(baker's yeast, enzyme preparations, some vitamins, etc.) are produced. 
In the conditions of anaerobic respiration (digestion) - mainly products that 
should contain ethyl alcohol (alcoholic beverages, wine, alcohol, etc.) are 
produced. 
II. The enterprises of the physico-chemical production group include white 
sugar, starch, vegetable oils, confectionery products and other production 
technologies. The process that summarizes them is the separation of necessary, 
useful substances from the raw materials by physical methods and processing by 
chemical methods. The main process in this is extraction or diffusion. For 
example, starch is obtained by washing (extraction) with water from crushed raw 
materials. An example is to dissolve some juices, white sugar (sucrose) from sugar 
beet, and vegetable oils from kunjara with gasoline. 

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III. Production based on mechanical-thermophysical processes covers many 
areas. Based on such technologies, mixing, separation, separation, grinding, 
grinding, pressure processing, etc., from mechanical processes; thermophysical 
processes include ventilation, drying, boiling, frying, etc.These processes are 
common in flour, pasta, confectionery, canning, and oil production enterprises. 
IV. Chemical reactions are the basis of chemical productions. Such 
technologies are used in the hydrolysis of starch with inorganic and biocatalysts, in 
the production of glucose, in the hydrogenation or peretherification of oils, in the 
production of various solid fat products and soap, in the hydrolysis of ethylene, in 
the production of ethyl alcohol, etc. 
Each of the four considered groups of production has its own basic 
processes, their concepts and laws. Below we will get acquainted with the basic 
concepts of the processes belonging to each group and describe the main laws. 
Microbiological and biochemical processes form the basis of fermentation 
technology in the production enterprises of the first group.These processes are 
carried out with the help of enzymes in raw materials or secreted by 
microorganisms. It is known that enzymes are biocatalysts, their nature, types, 
distribution in nature, properties were fully introduced in the "Biochemistry" 
course. Another force driving biotechnological processes is yeast. They are single-
celled microorganisms, the complete information about their structure, types, 
reproduction, etc., is fully studied in the course "Microbiology". As for the impact 
of microorganisms on raw materials in technological processes, the product is 
produced as a result of biochemical changes with the participation of enzymes 
synthesized and released as a result of their life activity. Different microorganisms 
synthesize different enzymes. For example, in the production of alcohol, amylase 
enzymes of mold fungi or malt (harvested barley) are converted into starchy mono- 
and disaccharides of wort (intermediate product), and then alcohol is produced 
from them under the action of enzymes of special yeasts. In beer production, 
ethanol, polyhydric alcohols and other substances determining the taste of beer are 
produced under the influence of complex (various) amylolytic and proteinase 
enzymes and yeasts contained in malt. Such examples can be seen in winemaking, 
acetone production, production of citric and lactic acids from nutrient acids, tea 
and tobacco fermentation processes. polyatomic alcohols and other substances 
determining the taste of beer are produced. Such examples can be seen in 
winemaking, acetone production, production of citric and lactic acids from nutrient 
acids, tea and tobacco fermentation processes. polyatomic alcohols and other 
substances determining the taste of beer are produced. Such examples can be seen 
in winemaking, acetone production, production of citric and lactic acids from 
nutrient acids, tea and tobacco fermentation processes. 
In the second group of productions, extraction and pressing methods are the 
most common methods of extracting important, useful substances from raw 
materials. Extraction processes in the food industry include sugar from sugar beets; 
pectin substances from apple juice; in winemaking, the salts and sugar of tartaric 
acid entering the wine bouquet from the grapes; enzyme preparations from primary 
fungal raw materials in pharmaceuticals; In the oil industry, an example is 

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technology such as extracting oil from oil. If the extraction method is cost-
effective, the products extracted by presslab are considered to be of high quality. 
Therefore, it is effective to use both methods in succession. 
Extraction is defined as the process of dissolving and separating one or more 
substances from a complex mixture of various substances with the help of a 
selective solvent. The extraction of soluble substances from the cell in the raw 
material is a two-step process. In the first stage, the solvent diffuses into the raw 
tissue, and in the second stage, substance transfer from the raw material to the 
solvent takes place. The basic law of molecular diffusion, described by Fick, 
determines the relationship between the amount of the extracted medium and the 
main parameters (indicators) of the process: 
D is the diffusion coefficient, a physical parameter of the raw material, 
which is equal to the amount of fashion that diffuses from a unit surface per unit 
time when the concentration gradient of this raw material is equal to one. The unit 
of measurement is m2/s. 
This equation can be used only if the concentration of the substance does not 
change, if the solvent does not accumulate in the raw material. However, in the 
process of extraction, the concentration of the substance in the raw material is 
constantly reduced. Therefore, such problems are solved by special differential 
equations. 
In the second stage of the extraction process, the extracted substance moves 
from the surface of the solid raw material to the liquid phase due to molecular 
diffusion and convection. This process is more complicated, but in engineering 
practice, the following equation is used: 
Unlike the diffusion coefficient, the mass transfer coefficient is not a constant 
value and depends on the size and shape of the crushed raw materials, the physical 
properties and speed of the solvent, the temperature of the process, etc. 
The basic concept of the extraction process is that the driving force behind 
the extraction is the concentration difference. 
Purification-refining. The phase extracted from the plant raw material, 
regardless of the type of extraction method, must be further purified. In the food 
industry, cleaning is called refining. Below are some common cleaning methods. 
Physical and physico-chemical methods of cleaning are known. Physical methods 
of cleaning liquids include filtration, separation, processes. 
Settling is the settling of small particles in a liquid under the influence of 
gravity. The rate of settling depends on the particle density, size and physical 
properties of the liquid. In the industry, mainly periodic and continuous quenchers 
are used. The main law of the settling process is that the efficiency of the 
equipment depends not on their height, but on the size of the settling surface and 
the settling speed of the particles. 
Filtration is the separation of the liquid phase by trapping the particles in 
suspensions with the help of porous barriers. The driving force of this process is 
the pressure difference in front of and behind the barrier. This difference in 
pressures is due to the transfer of the filtered suspension with the help of a pump or 
hydrostatic pressure; at the expense of creating a vacuum; is generated due to 

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compressed air pressure. In the food industry, filtration through a barrier and 
sedimentation layer is widely used. If the suspension has a low concentration and 
the particles are very small, special filtering substances (diatomite, perlite, 
cellulose, asbestos, etc.) are applied to the surface of the barrier to prevent 
clogging of the pores. These substances are used by adding up to 1% to the 
composition of the suspension. Ram, cartridge, drum, disc and vacuum filters are 
widely used in the industry. The main laws of the filtering process are as follows. 
As the layer thickness increases, if the pressure difference does not change, the 
filtration rate decreases.If the pressure difference increases with the increase in 
layer thickness, the filtration rate becomes constant. Hence, the rate of filtration is 
directly proportional to the pressure difference and inversely proportional to the 
total resistance of the barrier and the bed. 
Adsorption and deodorization processes are examples of physico-chemical 
cleaning methods. As you know, adsorption is the absorption of one or more 
components from a solution onto a solid surface. Adsorption can be selective and 
reversible. Porous solids (activated carbon, silica gel, cellulose mass, kieselguhr, 
bleaching earth) are used as adsorbents. Whitening in sugar production, 
winemaking, juice extraction and cottonseed oil production is carried out by the 
adsorption method. Adsorption is either physical or chemical. In chemical 
adsorption, in contrast to physical adsorption, a chemical reaction and a chemical 
bond occur between the molecules of the adsorbent and the absorbed substance. In 
industry, processes are divided into periodic and continuous types, mainly 
according to whether the adsorbent is in a stationary or mobile state. 
Deodorization is the evaporation of odorous substances under certain 
conditions without harming the quality of the processed product. Evaporation is 
carried out by mixing with hot steam. This process is mainly used for spotting oils. 
To prevent oxidation of the oil, it is necessary to ensure that the steam does not 
contain oxygen. 
Melting and crystallization. Crystalline substances are soluble. We have 
considered the application of the melting phenomenon in the extraction process in 
the food industry. Bringing the solute from the solution back to the crystalline state 
is the second stage of the white sugar (sucrose) production process. As we can see 
in the example of sucrose, it can only go from a supersaturated solution to a 
crystalline state. Crystallization centers are formed by growing crystals and 
keeping the solution in a supersaturated state by boiling. Supersaturation is 
measured as the ratio of the amount of solute in the solution to the amount of water 
in the solution. This coefficient is called supersaturation coefficient. If the solution 
contains non-sugar substances, the solubility of sucrose in such a solution increases 
again. 
Basic concepts of rheology. The main rheological properties of raw 
materials and products of the food industry include viscosity, tension, elasticity 
and strength. The same material may exhibit different properties depending on the 
condition and type of exposure. For example, pasta dough exhibits tension when it 
is quickly forced back. If a slow continuous force is applied, viscosity and 
viscosity will show. In many technological processes, the processed material goes 

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from one rheological state to an absolutely opposite rheological state, and in some 
cases it partially changes. First, densification occurs due to the loss of air or liquid, 
and then plastic deformation occurs due to the densification of material particles. 
Raw material, Studying the rheological properties of semi-finished products and 
products provides an opportunity to connect the construction of technological 
equipment, the dependence and kinematics of the main parts with the physical and 
mechanical properties of the material being processed. Studying the volumetric 
deformation of the material mass in the conditions of lateral compression under 
pressure provides an opportunity to solve the distribution of pressure within the 
volume of the mass, the degree of material compression, the relationship between 
material density and pressure, and other issues. This, in turn, provides an 
opportunity to provide pressure in technological processes, which positively affects 
the quality of the final product. Studying the volumetric deformation of the 
material mass in the conditions of lateral compression under pressure provides an 
opportunity to solve the distribution of pressure within the volume of the mass, the 
degree of material compression, the relationship between material density and 
pressure, and other issues. This, in turn, provides an opportunity to provide 
pressure in technological processes, which positively affects the quality of the final 
product. Studying the volumetric deformation of the material mass in the 
conditions of lateral compression under pressure provides an opportunity to solve 
the distribution of pressure within the volume of the mass, the degree of material 
compression, the relationship between material density and pressure, and other 
issues. This, in turn, provides an opportunity to provide pressure in technological 
processes, which positively affects the quality of the final product. 
Thermophysical descriptions of food products and principles of optimal 
thermal processing. Heat and mass transfer phenomena are important in 
technological processes. In most cases, these are non-stationary and irreversible 
processes that lead to changes in the properties, structure and quality of raw 
materials and semi-finished products. 
Food industry raw materials and materials are heterogeneous systems, solids 
and gaseous liquids with different structures. The thermophysical parameters of 
such materials depend primarily on their chemical composition and moisture 
content, and may change significantly during processing. It should be taken into 
account that the method and speed of heating or cooling can change the structure 
and properties of the product in different ways. By studying the thermophysical 
dimensions of materials, evaluating the thermophysical properties of food products 
and correctly connecting them with the technological processes of processing, 
ensures the quality of the product. 
The optimally selected thermal conditions of the processing process ensure 
the production of high-quality products with high productivity and economic 
efficiency. 
Review questions 
1. Classification of food industry enterprises by types of raw materials. 
2. Types of primary and secondary processing enterprises of plant raw 
materials. 

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3. Duties of storage of raw materials. 
4. Specific quality indicators of raw materials. 
9. Division of processing methods into groups. 
10. Productions based on curing. 
11. Physico-chemical productions. 
12. Productions based on mechanical-thermophysical processes. 
13. Chemical productions. 
14. The essence of processes involving enzymes and yeasts. 
15. The nature and application of pressing and extraction processes. 
16. The essence of filtering and filtering processes. 
17. Nature and application of adsorption and deodorization processes. 
18. The essence of melting and crystallization processes. 
19. Importance of rheological indicators of food raw materials and products. 
20. The concept of optimal thermal treatment. 
"Basic" words and phrases 
Plant raw materials, animal raw materials, types of enterprises, physico-
chemical losses, biological losses, chemical losses, storage tasks, storage 
principles, 
post-harvest 
ripening, 
resting 
state, 
fermentation, 
enzyme, 
microorganism , yeast, pressing, extraction, fermentation, filtration, adsorption, 
deodorization, dissolution, crystallization, rheological index, thermal treatment.