Agriculture 4. Technologies of storage and processing
of agricultural products
Assoc. Prof. V.Yu. Ovsyannikov, student A.N. Denezhnaja,
student T.S. Kirichenko, student Yu.S. Kraminova
Voronezh State University of Engineering Technologies,
Russia
Analysis of
the methods of the concentration of the extract of the pancreas of large
livestock
The
sphere of the carrying out and the rotation of medicines are one of the
elements, which ensure the national security of Russia, and directly it depends
on the state of the economy of the country.
By the
most important task of domestic medical industry is satisfaction of the need of
public health and population of the country for highly effective, qualitative
and safe pharmaceutical production one of the most important forms of raw
material for which they appear the organs of slaughter animals, obtained from
large, small livestock and pigs.
Evaporation
is the basic industrial method of the concentration of the aqueous extracts of
endocrine raw material. Because of termolabilnosti of protein and number of
other substances the thickening is accomplished in the vacuum, at a reduced
boiling point. However, it is impossible completely to eliminate the negative
effect of thermal effect on the sensitive protein-carbohydrate raw material.
So
vacuum the evaporation of the extract of the pancreas of large livestock is
accompanied by the irreversible denaturing of some fractions of proteins. As a
result the prolonged working of extracts into the vacuum apparatus the partial
coagulation of proteins is accompanied by the formation of elaborate protein-
mineral complexes. In the extracts appears flake-shaped sediment of the gray or
auger brown color, the process of accumulation of which depends on the degree
of thickening and bears exponential nature.
A
prolonged thermal effect and an increase of the acidity in the process of
thickening is accompanied by the partial hydrolysis of fatty and carbohydrate
complexes with the formation of the complexes of organic acids, which decreases
the quality of the concentrated product.
In
connection with that presented special attention deserves the thickening by the
freezing out method of moisture or freeze concentration. Method is based on the
phenomenon of the crystallization of moisture during cooling of aqueous
solution down to the temperature lower than cryoscopy. The process of freezing
moisture is accompanied by a continuous increase in the concentration of dry
matter and, therefore, by continuous depression of the freezing point of
solution. Dependence between depression of the freezing point and concentration
is connected not only with the growth of a total quantity of dry matter, but
also with the concentration, expressed by the number of particles of the
dissolved substance per unit of volume of solvent.
For
this reason the presence of the substances, which are distributed in the
multicomponent solution with different degree of dispersion, respectively
unequally influences the freezing point of solution. The presence of the
colloidal degree of dispersion and high-molecular connections practically does
not influence freezing point in comparison with the molecular substances.
By the
purpose of this work was study and comparison of the quality indicators of the
aqueous extracts of the pancreas of large livestock of those concentrated
vacuum evaporation and freezing under laboratory conditions.
The measured
volumes of the extracts of the pancreas were subjected to vacuum- evaporation
at the laboratory vacuum to evaporator at a residual pressure by 19,6… 20,2 kPa
and a temperature of 60 °S with the periodic sampling for determining the
content of dry matter. After thickening of solution to the specific content of
its dry matter were quenched to the temperature 20 °С with the aid of the thermostat UTU-2.
Freezing moisture
from the tested products was conducted in the cooling chamber of the
low-temperature table of frigera HC 280/70.1 with by the gravity circulation of
air with the temperature – 30 °C. the temperature of cooling extract, cryoscopy
temperatures and the cooling time measured and recorded with the aid of the twelve
point potentiometer KSP-4 (class of precision 0,5) with the collection of
Chromel-Copel thermocouples (diameter of joint 0,5 mm) and the electronic
stopwatch.
After the necessary
holding time they extracted extract from the camera of refrigerator table and
transferred into the cuvette of the hand press, where was separated the frozen
out moisture in the form of ice from the concentrated liquid by extrusion under
pressure 16… by 20 kPa.
The extracts,
obtained by evaporation and freezing of moisture subjected vacuum to
organoleptic and physical chemistry analysis [3].
The analysis of obtained
data shows that the color in the concentrate of the extract of the pancreas,
obtained freezing better remains than during the vacuum evaporation. The
content of protein substances and fats in the extract of the pancreas, obtained
vacuum by evaporation somewhat lower than in analogous that frozen out, and the
value of the titrate acidity is above.
It should be noted that
the activity of the extract of the pancreas of that concentrated by freezing
proved to be somewhat higher than with the concentration of analogous extract
vacuum by evaporation, whishes indicate the best retention of the ferments of
the gastric juice: trypsin and chymotrypsin, that cause the proteinaznuyu The
analysis of the organoleptic and physical chemistry indices of extracts,
concentrated by freezing and vacuum by evaporation shows that the method of
concentration to a considerable degree determines the quality of the extracts
of the pancreas. The vacuum evaporation of moisture, utilized at present, does
not always ensure the retention of the quality of aqueous extracts with the
concentration, due to the destruction of protein, fatty substances, and amino
acids.
Thus, it is experimentally proven that the
concentration makes it possible to completely ensure the retention of the
organoleptic and physical chemistry properties of the extract of the pancreas
with freezing, unambiguously indicating the advantage of this method of the
concentration of products, necessary for obtaining of a whole series of the
medical preparations, utilized for treating the diseases of stomach.
The method of
concentration by freezing yet does not have wide acceptance, since obtaining
cold - more expensive process than obtaining water vapor. Because of the high cost
of refrigerator equipment the process of concentration by freezing with the
second heat removal is approximately 2 times more expensive than the process of
evaporation with the catching of aromatic substances.
The maximum
concentration of dry matter, which it is possible to reach, is limited by the
viscosity of the concentrated product at freezing temperature and by the
eutectic point of solution, with which it is not possible to separate water in
the form of ice.
They do not reach
high degree of concentration, since for this it is necessary to considerably
lower the temperature of initial product. The magnitude of losses of solutes is
also the important criterion, which determines optimum degree of concentration:
the higher the concentration, the greater the loss.
But, in spite of above-enumerated deficiencies,
concentration freezing remains the bezalternativnym method of thickening
product with the maximum retention of initial chemical composition [4, 5].
Literature
1. The pancreas of large livestock and pigs frozen.
Technical specifications. ALL-UNION STATE STAN. 11285-73. M.: Publishing house
of standards 1973 g. - 4 p.
2. Reference book on
the production of organic preparations, Gurov v.a., Inozemtseva M.A.,
Zamikhovskiy A.B. M.: Food industry, 1970. - 348 p.
3. Physical chemistry
and bacteriological control in the meat industry. Kogan PERHAPS, Pozhariskaya
L.S., Ryndina A.P., Freydlin E.M. M.: Food industry. - 1971, 462 p.
4. L. Pap Freeze concentration. Translation.
with Hungarian, edited by O.G. Komyakova. - M.: Light and Food Industry, 1982.
- 97 p.
5.
Ovsyannikov V.Yu. Study of the process of freezing moisture from the extracts
of the endocrine and special raw material. Diss. cand. tech. the sciences.
Voronezh. State. tech. Acad., 2003. 184 p.