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faces. Thus there is a transition from a liquid substance into a solid phase as a
result of the emergence and growth of crystals in solution. Crystallization is
usually performed in aqueous solutions. By lowering the temperature or removal
of the solvent decreases the solubility of a solid. The solution becomes
supersaturated, and the solid precipitates out of solution in the precipitate.
In food technology selection solids from solutions or melts as a crystalline
product is the final stage of the technological process of sucrose, glucose, salts
and other crystalline products. However, in many industries as a crystallization
phenomenon occurs in conjunction with other processes. For example, in the
production of butter, high fat cream conversion method of mixing multiple
quenched layers of cream with warm contributes to the massive nucleation.
There comes a critical moment of mass destruction membranes of the fat
globules, and phase inversion occurs.
By the heat exchanger includes such processes, in which the supply or
removal of heat: heating and cooling, evaporation, condensation. Heat exchange
between the two heat transfer fluids through the separation of the solid wall
called heat transfer. Coolant - a moving medium used to transfer the heat. As the
coolants in the food industry most widely used saturated steam, water,
combustion gases, air, and as refrigerants - ammonia, freon, brine, calcium
chloride, air, nitrogen.
Warming as a process step is present in almost all food industries. For
example, in direct contact with the heated coolant made of animal fat melting out
food from a soft raw fat, cooking sausages and savory products. The flue gases
are used for smoking meat - and fish products, sausages. The hot air used in the
preparation of dry dairy products and so on. D. Heating the wall through the
contact, such as pasteurization or sterilization, occupies a very important place in
any food technology. For example, in the dairy industry, this operation is
optional in the preparation of any dairy product, ie. K. Aim of inactivation of
microflora to further correct process.
To cool the products in food technology to 15 - 20 ° C using water and air.
For cooling products to lower temperatures using low-temperature refrigerants -.
Refrigerating brines, refrigerants, ammonia, etc. Cooling is also a very important
step in the food production. Raw materials, semi-finished and finished goods
cooled after heat treatment for further operations. Cooling treatment is used as
an alternative preservation and backup products. Evaporating - concentrating this
process solutions of low-volatile or non-volatile solid substances by evaporation
of the volatile solvent, and removing the vapors formed. The aqueous solutions
were evaporated in food technology.
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