This study assessed the potential use of various physiological stress biomarkers as indicators of carcass and meat quality traits in 240 pigs subjected to the standard marketing conditions and minimal stressful antemortem handling using Pearson correlations. The most important pork quality traits (pH and temperature, water holding capacity, and color) had limited correlations with stress metabolites (lactate, glucose), stress hormones (cortisol, adrenocorticotropic hormone), stress enzymes (creatine kinase, aspartate amino transferase, alanine amino transferase), electrolytes (sodium, chloride), and acute-phase proteins (haptoglobin, C-reactive protein, albumin), indicating poor reliability in predicting pork quality. Albumin level was moderately positively correlated with live weight, hot carcass weight, cold carcass weight, and back fat thickness. Alanine amino transferase level was moderately positively correlated with live weight, hot carcass weight, and cold carcass weight. Cortisol level was moderately positively correlated with live weight, hot carcass weight, cold carcass weight, and back fat thickness, and moderately negatively correlated with the lean carcass content. Increased lactate dehydrogenase level was moderately correlated with decreased drip and cooking loss. In conclusion, lactate dehydrogenase could help pork producers predict pork quality variation, while cortisol, alanine amino transferase, and albumin could be useful in prediction of carcass quality.

ИНУЛИН КАК ПРЕБИОТИК И ЗАМЕНИТЕЛЬ ЖИРА В МЯСНЫХ ПРОДУКТАХ

The purpose of food packing in modified atmosphere is to extend its sustainability by preventing both biochemical processes and growth of spoilage bacteria. Gases or their mixtures which are mostly used in the modified atmosphere food packing technology are carbon-dioxide (CO2), oxygen (O2) and nitrogen (N2). The aim of our research was to examine the influence of packaging in modified atmosphere and vacuum on the total volatile basic nitrogen (TVB-N) content and pH in muscle of rainbow trout (Oncorhynchus mykiss) and common carp (Cyprinus carpio), as well as to determine the most suitable gas mixtures for packing of these freshwater species. Three sample groups of trout and carp cuts were investigated. The first two groups were packaged in modified atmosphere with different gas ratios: 60%CO2+40%N2 (I group) and 40%CO2+60%N2 (II group), whereas the samples from third, control group, (III group) were vacuum packaged. During trials samples were stored in refrigerator at +3?C. Determination of TVB-N and pH was performed on 1st, 7th and 14th day of storage. The obtained results indicate that the investigated mixtures of gases and vacuum as well had a significant influence on the values of TVB-N in trout and carp cuts samples. The lowest increase in TVB-N was established in trout and carp cuts samples from the group I, whereas the highest increase was established in samples from group III. Statistical significant difference (p < 0,001) between the average values of TVB-N for trout (I group: 18,17 ? 0,93; II group: 20,90 ? 0,81 and III group: 36,18 ? 2,65 mg N/100 g ) and carp cuts (I group: 26,74 ? 1,48; II group: 30,02 ? 0,31 and III group: 35,10 ? 1,75 mg N/100 g) was established on 14th day. The lowest pH value was established in samples packaged in modified atmosphere with 60% CO2 +40% N2 (I group). On 14th day of testing the obtained value was 6,15 ? 0,09 for trout and 5,94 ? 1,11 for carp samples. Increase in pH value in trout samples packed in vacuum was established during the whole period of investigation (p < 0,001), while in carp cuts samples packaged in vacuum the increase in pH value (p < 0,05) was established up to 7th day of testing. Based on the obtained results it can be concluded that gas mixture consisting of 60% CO2 and 40% N2 was the most suitable for packaging of fresh trout and carp cuts in terms of selected chemical parameters, such as TVB-N and pH.

In order to satisfy the increasing demand for food production which will reach the consumers in a safe condition, and at the same time meet their expectations in terms of quality, the packaging industry has been continually developing and striving to implement new technologies such as nanotechnology. By application of nanoparticles and other nanomaterials of various organic and inorganic compounds in standard packaging materials, the quality of packaging such as polymer-flexibility, gas barrier properties, temperature/moisture/ light stability, thermal and chemical stability and biodegradability has been improved. Moreover, the use of polymer nanotechnology enables constant monitoring of packaging conditions, providing in that way the preservation of fresh food, extension of shelf life of foods and improvement of products quality and safety. The application of nanopackaging on the market is slowed due to lack of data on potential risk to human health and the impact on the environment, as well as to lack of legal regulations. These shortcomings affect public perception of nanotechnology, but when these problems are overcome application of nanopackaging promises to become an irreplaceable part of industrial production of food.

Salmonella is one of the most important zoonotic pathogens and the consumption of pork meat is one of the major sources of human infection. The aim of this study was to investigate the presence of salmonella on pig carcasses. Samples were taken from slaughterhouse A in two instances (sampling I and II, a total of 300 samples) and in slaughterhouse B once (sampling III, a total of 120 samples), from pork carcasses after the stunning and after the processing. Of the total number of examined samples, the percentage of positive samples for salmonella from pork carcasses after stunning was 46.7% (90/42), and samples from the carcasses after processing 3.3% (90/3). Operations taking place on the slaughter line could have an effect on the salmonella contamination of carcasses.