ANALYSIS OF QUALITY INDICATORS OF CHILLED AND FROZEN BEEF

Introduction. In countries of Europe are implementing mechanisms for the humane treatment with farm animals, which provides also minimizing the pain and suffering of animals during slaughter. For this, government of EU in 2009 year adopted the corresponding Regulation № 1099/2009. 
Established, that stress before slaughtering animals leads to an increase the level of catecholamines and creatinekinase in their organism, which causes rapid glycolysis, during which accumulates lactic acid in the meat. This leads to a decrease level of glycogen, which causes change pH of the meat and capacity holding the water, the meat acquiring tougher and darker color. 
In Ukraine many Ukrainian enterprises of the meat industry received certificates, that attesting the accordance of their products the conditions of "Halal", which opens for them the way to new markets of selling the meat of beef. 
However insufficiently studied remains the issue of storing the qualitative indices of halal meat during transportation on long distance. The data about study the date of expiration such meat also absent. 
The purpose of this work was to study the qualitative indices of cooled and frozen meat of certified beef of breed of Aberdeen-Angus, to establish the date of expiration. 
Research materials and methods. The object of the research: cooled and frozen meat of beef obtained from cattle of breed of Aberdeen-Angus of the company "HALAL MEAT COMPANY" is packed in vacuum bags for establish the date of expiration during storage for 16 months. 
In order to conduct the research were taken three samples of halal beef of the Aberdeen-Angus breed: sample № 1 – a neck cut from the scapular part of the carcass, sample № 2 – marbled beef for pork from the scapular part of the carcass, sample № 3 – marbled beef classic from the breast part of the carcass. 
The pH of the meat was determined on a pH meter Delta OHM HD2305.0 the Italian company SIMVOLT with a electrode KP70. 
Organoleptic evaluation of the product carried out in accordance with DSTU 4589:2006, determination of the number of mesophilic aerobic and facultatively anaerobic microorganisms - in accordance with GOST 10444.15, detection of bacteria of the group of Escherichia coli - in accordance with GOST 21237. 
Research on the presence bacteria of L. monocytogenes carried out according to DSTU ISO 11290-1, and the presence bacteria strain of Salmonella carried out in accordance with GOST 21237. 
The results processed by methods of variational statistics with using the standard package of programs of Microsoft Excel. 
Research results. When measuring the level of pH it established, that in the cooled test samples it was within the normal range and was: sample № 1 – 5.83, sample № 2 – 5.74, sample № 3 – 5.79. When they were stored after thawing the pH decreased. Thus, after 4, 12 and 16 months of storage, the pH of experimental sample № 1 was 5.25; 5.16 and 5.20; sample № 2 – 5.29; 5.21; 5.18; sample № 3 – 5.24; 5.17 and 5.21. 
After thawing the test samples, that were stored, occurred loss the moisture. Thus, when they were stored for 4 months the loss of moisture after thawing for sample № 1 was 5.2%, sample № 2 – 4.9%, sample № 3 – 4.3%. 
When carrying out organoleptic studies it established, that in all thawed test samples detected signs change of color after 4 months of storage and signs of spoilage after storage of 16 months. 
After carrying out microbiological studies it established, that pathogenic microorganisms such as Salmonella and L.monocytogenes detected in samples of thawed meat, which had been stored for 16 months. The number of mesophilic aerobic and facultatively anaerobic microorganisms during storage increased. Thus, in the cooled meat of sample № 1, sample № 2, and sample № 3, this indice was 6.8*103; 6.1*103 and 5.7*103, which did not exceed the requirements of the standard. For thawed test samples after 12 months of storage this indice increases: sample № 1 – 4.6*104, sample № 2 – 3.9*104, sample № 3 – 4.0*104. Exceeding the requirements of the standard of thawed samples of meat noted after 16 months of storage, which leads to their spoilage. 
Conclusions. In result of the conducted research it established, that the pH of all experimental samples of cooled meat of beef was within the normal range and was in average 5.78. 
During storage of experimental samples after their thawing, the pH decreased, which is associated with damage to fibers of meat caused by the formation crystals of ice during freezing and thawing. 
Also, when were stored the experimental samples for 4 months the loss of moisture after defrosting was from 4.3% in sample № 3 to 5.2% in sample № 1. 
The change the level of pH in the experimental samples and loss their moisture affected on organoleptic indices: changed the appearance of the meat, color, it has lost the juiciness. 
The number of mesophilic aerobic and facultatively anaerobic microorganisms after 16 months of storage exceeded the established standards according to GOST 10444.15. 
In the course of research it was established, that the recommended date of storage of halal meat of beef of breed of Aberdeen-Angus is 12 months at a temperature of -18...-25°С in vacuum packs.