the oxidation processes, maximally preserve sensory, the properties and biological
value. The advantages of the cryogenic freezing are minimally changing the nutritional
and biological value of the fruits and vegetables, maximizing the mass of the product
and the possibility of organizing the production in confined areas with the use of simple
technological equipment. The main disadvantage of this freezing method is the high
cost of the liquefied nitrogen. A new method of the cryogenic contact freezing in
conventional type cells using granular carbon dioxide is characterized by a reduction
in production costs [11].
To reduce the negative physical and chemical changes that occur during the
freezing and storage of the plant material, namely drying and oxidation, the packaging
of products in containers of different types of packaging materials is used [12-14]. The
optimum packaging of the frozen fruits and vegetables in terms of preserving their
consumer properties is the packaging of polymer materials. It is proved that the degree
of weight loss of fruits and vegetables is directly proportional to the vapor permeability
of the packaging material. However, if the seal is impermeable, the evaporating
moisture will settle in the form of frost on the inner surface of the packaging material
which makes it impossible to visualize the product.
One of the factors of preservation of the quality of the products formed during
freezing is the observance of the optimum conditions for its storage. According to the
recommendations of the scientists the storage temperature should not exceed minus
18ºС. However, the studies of the recent years have established that this temperature
does not guarantee the complete crystallization of the moisture.
The high level of the frozen production formed during the production process,
during its life cycle can not be preserved without the integrity of the refrigeration chain
and the corresponding temperature regimes on each of its components. The failure to
comply with the requirements for the integrity of the refrigeration chain at any of the
units is accompanied by recrystallization, defrosting, laceration, loss of cellular juice
and soluble dry matter, including vitamins. At the same time the enzymatic activity
increases, the oxidation processes are intensified, and the consumer properties of the
fruits and vegetables decrease.
The final link in the complex chain of the formation and preservation of the quality
of the frozen fruit and vegetable products is its preparation for consumption. In case of
violation of the recommended methods of defrosting (with the use of surface or internal
heating), or unsatisfactory performance of the product the quality can significantly
deteriorate.
In view of the above, we have developed a functional model of production as a
control system (Fig. 1). Its elements are subsystems of the market, science, production
with internal and external coordination and subordination relations.
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