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FSB1- 2004
Food Science and Biotechnology in Developing Countries
coagulated plasma, and agitated for 3 min, decanted again this operation was reported. The washed
coagulated plasma was placed on a gauze and it was pressed manually to eliminate the excess of water.
The plasma was placed inside a plastic bag, closed and stored in refrigeration at 4 ºC Effect of the time,
among the bleed of the animal and the refrigeration of the blood, and the time of refrigeration of the blood
before the separation and clotting (TRASC) in the yield and microbial contained of coagulated plasma. By
means of a factorial design 2x4x2 were studied: the time among the bleed of the animal and the
refrigeration of the blood (1 or 4 h, approximately at 37ºC) the (TRASC) (18, 42, 66 and 90 h) the
temperature of the laundry water (20 or 80ºC). Determination during storage (TRASC) the pH, total solids
for evaporation at 100ºC during 4 h and the total count of aerobic mesophilic . The yield was defined as
the quantity of solids recovered in coagulated and washed plasma by each 100g of solids of plasma
without coagulating ..During the storage at 4ºC, was determined the total count of aerobic mesophilic at
the 7 and 14 days. Effect of the addition of acetic acid and atmosphere of CO2 in the of shelf life of
coagulated plasma. Prepared samples of 100g of coagulated and washed plasma, with 48 and 67 h of
storage at 4ºC before cotting were added 0 and 0.5% of glacial acetic acid before their storage, it was also
made happen or not, a current of CO2 (4 Kg/cm2 for 2 min) in the bags containing the coagulated plasma,
the samples were stored at 4ºC. The determinations were carried out at the same times and under the
same conditions that in the previous experiment. Use of plasma proteins (PP) in Ground meat (GM) for
preparation of beef patties. Commercial ground meat was used, plasma proteins were obtained from the
recovery plant of FIRASA Company and pig fat (G) from the same company. Determination of pH,
protein, ether extract , ash, humidity and total count aerobic mesophilic were done by conventional
methods. For the shelf life, the samples were: GM, PP+10% of G, GM+10%(PP+10% G) they were
maintain in refrigeration (3°C) and freezing (-13°C). For the sensorial analysis 96 hamburgers, for each
treatment were prepared. .The formula for each treatment were: GM100%, GM90%+10%(PP+10%G) and
GM 80%+20%(PP+10%G). To all the samples was added 0.2% of salt. Cooked samples were offer to 64
panelist and requested they ordered the three samples offered for their preference by the attributes
appearance, odor, texture and flavor.
RESULTS AND DISCUSSION
Effect of the time, among the bleed of the animal and the refrigeration of the blood, and the time of
refrigeration of the blood before the separation and clotting (TRASC) in the yield and microbial contained
of coagulated plasma.
In the Table 1 the results of the effect of time between the bleed of the animal and the refrigeration are
presented and the time of storage of the blood (TRASC), in the obtaining of the coagulated plasma; as it is
observed a high significance it exists on the pH, of the time among the bleed of the animal and the
refrigeration of the blood, and of the time of refrigeration of the blood before the separation and clotting
(TRASC), since the values of pH of the blood maintained at 37ºC during 4 h are consistently bigger than
those only maintained 1 h, and in what concerns at the time of storage (TRASC) as this happens there is
a pH increase until the 66 h, this is accountable from the point of view that this situation is usually
presented when the substrate of the microorganisms is only protein, (like in the case of the blood), since
so that these can use it as source of carbon it should exist a proteolysis and a production of ammonia like
consequence of the liberation of the group amino of the amino acids and they use this way as source of
carbon the sour carboxylic acids, however, between the 66 and 90 h this effect no longer present
significant difference.
In what concerns to the humidity of the coagulated plasma, the time among the bleed of the
animal and the refrigeration of the blood had a significant effect where the humidity of the obtained
coagulated plasma maintained 4 h at 37ºC is higher to the obtained of plasma refrigerated 1h after
bleed. The time of storage (TRASC) it also affects in significant form the water contain of the coagulated
plasma having a tendency to obtain minor contain of water when the time increase ; this means that the
functional property of capacity of retention of water of the plasma is better maintain when the blood is at
37ºC and with short time of storage.
From our results it is deduced that they recover of proteins is between 70 and 80% of the
proteins contained in the plasma and that the time of storage of the plasma before coagulating (TRASC)
has a negative effect in the yield, because during the storage there is microbial growth and therefore
proteolysis, what affects the gelification properties, this agrees with Howell and Lawre (1985), which study
the effect from the tripsin addition to the plasma and they observe a very important reduction of the
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