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The goal of this study conducted in Serbia was to detect HEV in pig liver samples from slaughterhouses, retail outlets, and environmental swabs over the course of a year. All positive HEV samples were measured and expressed as HEV gene copy numbers per gram of sample, and a representative number of samples were sequenced using the Sanger approach. A total of 45 HEVpositive samples were re-amplified using nested RT-PCR employing CODEHOP primers targeting ORF2 (493 nucleotides). The average prevalence of the HEV genotype 3 in all pig liver samples from the slaughterhouses was 29%, while HEV prevalence was 44% in liver samples from animals younger than 3 months. HEV RNA was found in thirteen out of sixty (22%) environmental swab samples that were taken from different surfaces along the slaughter line. Our findings confirmed seasonal patterns in HEV prevalence, with two picks (summer and winter periods) during the one-year examination. Among HEV-positive samples, the average viral particles for all positive liver samples was 4.41 ± 1.69 log10 genome copies per gram. Phylogenetic analysis revealed the majority of HEV strains (43/45) from Serbia were grouped in the HEV-3a subtype, while two strains were classified into the HEV-3c subtype, and one strain could not be classified into any of the HEV-3 subtypes.

This study presents the results related to changes in aw value and bacteriological status of fermented sausages during maturation without and with added starter culture, stuffed into a narrower and wider casing. Values of aw of narrower and wider diameter sausages with and without added starter cultures decreased during ripening, and were close to values of 0.9. Enterobacteriaceae in narrower diameter sausages were not detected on day 18, i.e., the end of the ripening process, and these bacteria were not detected in wider diameter fermented sausages on day 25 or at the end of ripening (day 35). The increase in the lactic acid bacteria in narrow and wider diameter sausages without added starter culture was slower than the increase in the number of these bacteria in sausages with added starter culture.

This study was conducted to determine the microbiological status of 390 beef and pork minced meat samples collected over three years from 52 retailers in the territory of Belgrade. The numbers of aerobic colony counts, Escherichia coli, and the presence of Salmonella spp. are prescribed criteria for this group of meat semi‑products. Salmonella spp. was confirmed in one sample of minced beef meat (0.8%), while unsatisfactory E. coli counts were only determined in pork meat samples (2.7%). In 2021, all samples complied with the microbiological criteria for minced meat The highest occurrence of positive samples was observed during the III quarter of 2022 (P=0.04) with a frequency of 9.3%. The level of contamination of minced pork with E. coli bacteria in the same quarter was significantly higher compared to the II quarter of 2022 (627±75 vs. 292±9 cfu/g, P=0.009). Improvement of process hygiene and revision of process control, along with permanent education of food staff on the principles of GMP and GHP, are necessary for maintaining food safety and public health.

Broiler meat quality depends on the interaction of several factors, including genotype, slaughter age/body weight, pre-slaughter handling, and slaughter method. The aim of this study was to determine the effect of slaughter weight on meat yield and quality of broilers. The material consisted of 42 broilers, classified into three groups: lighter (3000 g). The following meat yield parameters were measured: cold carcass weight, breast weight before and after deboning, breast skin and bone weights, thigh weight before and after deboning, thigh skin and bone weights, drumstick weight before and after deboning, and drumstick skin and bone weights. Meat pH (M. pectoralis major) and instrumental colour (breast and drumstick) were measured 24 h post-mortem. Meat quality classes (pale, soft and exudative and normal meat) were determined based on breast muscle L* value. Heavier broilers had higher (P<0.05) cold carcass weight, breast, thigh and drumstick weights both before and after deboning compared to medium and lighter broilers. In contrast, meat quality traits were not significantly (P>0.05) affected by slaughter weight. In conclusion, production of heavy broilers had a beneficial effect on meat quantity, while the effect of slaughter weight on meat quality was negligible., Kvalitet mesa brojlera zavisi od interakcije velikog broja faktora, uključujući genotip, starost/telesnu masu, postupaka pre i posle klanja. Cilj ovog ispitivanja bio je da se ispita uticaj telesne mase na prinos i kvalitet mesa brojlera. Istraživanje je sprovedeno na 42 brojlera, grupisanih u tri grupe: brojleri telesne mase manje od 2500 g, brojleri telesne mase između 2500 i 3000 g i brojleri telesne mase veće od 3000 g. Ispitivani su sledeći pokazatelji prinosa mesa: masa hladnog trupa, masa grudi pre i posle otkoštavanja, masa kože i kostiju grudi, masa karabataka pre i posle otkoštavanja, masa kože i kostiju karabataka, masa bataka pre i posle otkoštavanja i masa kože i kostiju bataka. Od pokazatelja kvaliteta mesa određivani su pH vrednost grudne muskulature, instrumentalno (L*, a* i b*) boja grudne muskulature, karabataka i bataka 24 časa nakon klanja. Meso brojlera je razvrstavano u klase kvaliteta (bledo, meko, vodenasto – BMV i meso normalnog kvaliteta) na osnovu L* vrednosti instrumentalno određene boje u M. pectoralis major. Brojleri velike telesne mase imali su veću masu hladnog trupa, kao i veću masu grudi, karabataka i bataka u poređenju sa brojlerima iz druge dve grupe. Nije utvrđen uticaj telesne mase na pokazatelje kvaliteta mesa brojlera. Stoga se može zaključiti da se klanjem brojlera velike telesne mase dobija najveći prinos mesa što predstavlja dobru sirovinu za dalju preradu. Sa druge strane, utvrđen je zanemarljiv uticaj telesne mase na kvalitet mesa brojlera.

Hepatitis E virus (HEV) is a zoonotic virus that can cause acute hepatitis in humans. Besides the fecal-oral route, transmission can occur by consumption of undercooked pig liver. Genotype 3 is the most frequent genotype found in Europe. Studies on HEV in slaughter-age pigs have not been conducted in Serbia so far. Pork meat production and consumption in Serbia is on average, higher than in the rest of Europe. With the aim to identify the circulating HEV genotypes, pig livers and swab samples from three pig slaughterhouses located in three different sub-regions of Serbia were collected. A nested RT-PCR was used to amplify the hypervariable HEV ORF-1 region (334 bp). The amplicons yielded in this study were sequenced, and a molecular phylogeny analysis based on the maximum likelihood method, including HEV sequences reported in several other countries, was performed. The average prevalence of HEV genotype 3 in 3-month-old pigs was 34%. Phylogenetic analysis revealed the majority of HEV amplification fragments from Serbia were grouped in four clades within sub-genotype 3a and were also genetically related to German, Italian, Slovenian, and American HEV sequences. Sub-genotypes 3b and 3j were also found in a single pig each. This study provides the first analysis of the genetic diversity and circulation dynamics of HEV in pigs at slaughterhouses in Serbia.

Broiler meat quality depends on the interaction of several factors, including genotype, slaughter age/body weight, pre-slaughter handling, and slaughter method. The aim of this study was to determine the effect of slaughter weight on meat yield and quality of broilers. The material consisted of 42 broilers, classified into three groups: lighter (3000 g). The following meat yield parameters were measured: cold carcass weight, breast weight before and after deboning, breast skin and bone weights, thigh weight before and after deboning, thigh skin and bone weights, drumstick weight before and after deboning, and drumstick skin and bone weights. Meat pH (M. pectoralis major) and instrumental colour (breast and drumstick) were measured 24 h post-mortem. Meat quality classes (pale, soft and exudative and normal meat) were determined based on breast muscle L* value. Heavier broilers had higher (P<0.05) cold carcass weight, breast, thigh and drumstick weights both before and after deboning compared to medium and lighter broilers. In contrast, meat quality traits were not significantly (P>0.05) affected by slaughter weight. In conclusion, production of heavy broilers had a beneficial effect on meat quantity, while the effect of slaughter weight on meat quality was negligible., Kvalitet mesa brojlera zavisi od interakcije velikog broja faktora, uključujući genotip, starost/telesnu masu, postupaka pre i posle klanja. Cilj ovog ispitivanja bio je da se ispita uticaj telesne mase na prinos i kvalitet mesa brojlera. Istraživanje je sprovedeno na 42 brojlera, grupisanih u tri grupe: brojleri telesne mase manje od 2500 g, brojleri telesne mase između 2500 i 3000 g i brojleri telesne mase veće od 3000 g. Ispitivani su sledeći pokazatelji prinosa mesa: masa hladnog trupa, masa grudi pre i posle otkoštavanja, masa kože i kostiju grudi, masa karabataka pre i posle otkoštavanja, masa kože i kostiju karabataka, masa bataka pre i posle otkoštavanja i masa kože i kostiju bataka. Od pokazatelja kvaliteta mesa određivani su pH vrednost grudne muskulature, instrumentalno (L*, a* i b*) boja grudne muskulature, karabataka i bataka 24 časa nakon klanja. Meso brojlera je razvrstavano u klase kvaliteta (bledo, meko, vodenasto – BMV i meso normalnog kvaliteta) na osnovu L* vrednosti instrumentalno određene boje u M. pectoralis major. Brojleri velike telesne mase imali su veću masu hladnog trupa, kao i veću masu grudi, karabataka i bataka u poređenju sa brojlerima iz druge dve grupe. Nije utvrđen uticaj telesne mase na pokazatelje kvaliteta mesa brojlera. Stoga se može zaključiti da se klanjem brojlera velike telesne mase dobija najveći prinos mesa što predstavlja dobru sirovinu za dalju preradu. Sa druge strane, utvrđen je zanemarljiv uticaj telesne mase na kvalitet mesa brojlera.

Broiler meat quality depends on the interaction of several factors, including genotype, slaughter age/body weight, pre-slaughter handling, and slaughter method. The aim of this study was to determine the effect of slaughter weight on meat yield and quality of broilers. The material consisted of 42 broilers, classified into three groups: lighter (3000 g). The following meat yield parameters were measured: cold carcass weight, breast weight before and after deboning, breast skin and bone weights, thigh weight before and after deboning, thigh skin and bone weights, drumstick weight before and after deboning, and drumstick skin and bone weights. Meat pH (M. pectoralis major) and instrumental colour (breast and drumstick) were measured 24 h post-mortem. Meat quality classes (pale, soft and exudative and normal meat) were determined based on breast muscle L* value. Heavier broilers had higher (P<0.05) cold carcass weight, breast, thigh and drumstick weights both before and after deboning compared to medium and lighter broilers. In contrast, meat quality traits were not significantly (P>0.05) affected by slaughter weight. In conclusion, production of heavy broilers had a beneficial effect on meat quantity, while the effect of slaughter weight on meat quality was negligible., Kvalitet mesa brojlera zavisi od interakcije velikog broja faktora, uključujući genotip, starost/telesnu masu, postupaka pre i posle klanja. Cilj ovog ispitivanja bio je da se ispita uticaj telesne mase na prinos i kvalitet mesa brojlera. Istraživanje je sprovedeno na 42 brojlera, grupisanih u tri grupe: brojleri telesne mase manje od 2500 g, brojleri telesne mase između 2500 i 3000 g i brojleri telesne mase veće od 3000 g. Ispitivani su sledeći pokazatelji prinosa mesa: masa hladnog trupa, masa grudi pre i posle otkoštavanja, masa kože i kostiju grudi, masa karabataka pre i posle otkoštavanja, masa kože i kostiju karabataka, masa bataka pre i posle otkoštavanja i masa kože i kostiju bataka. Od pokazatelja kvaliteta mesa određivani su pH vrednost grudne muskulature, instrumentalno (L*, a* i b*) boja grudne muskulature, karabataka i bataka 24 časa nakon klanja. Meso brojlera je razvrstavano u klase kvaliteta (bledo, meko, vodenasto – BMV i meso normalnog kvaliteta) na osnovu L* vrednosti instrumentalno određene boje u M. pectoralis major. Brojleri velike telesne mase imali su veću masu hladnog trupa, kao i veću masu grudi, karabataka i bataka u poređenju sa brojlerima iz druge dve grupe. Nije utvrđen uticaj telesne mase na pokazatelje kvaliteta mesa brojlera. Stoga se može zaključiti da se klanjem brojlera velike telesne mase dobija najveći prinos mesa što predstavlja dobru sirovinu za dalju preradu. Sa druge strane, utvrđen je zanemarljiv uticaj telesne mase na kvalitet mesa brojlera.

Hepatitis E virus (HEV) is a zoonotic virus that can cause acute hepatitis in humans. Besides the fecal-oral route, transmission can occur by consumption of undercooked pig liver. Genotype 3 is the most frequent genotype found in Europe. Studies on HEV in slaughter-age pigs have not been conducted in Serbia so far. Pork meat production and consumption in Serbia is on average, higher than in the rest of Europe. With the aim to identify the circulating HEV genotypes, pig livers and swab samples from three pig slaughterhouses located in three different sub-regions of Serbia were collected. A nested RT-PCR was used to amplify the hypervariable HEV ORF-1 region (334 bp). The amplicons yielded in this study were sequenced, and a molecular phylogeny analysis based on the maximum likelihood method, including HEV sequences reported in several other countries, was performed. The average prevalence of HEV genotype 3 in 3-month-old pigs was 34%. Phylogenetic analysis revealed the majority of HEV amplification fragments from Serbia were grouped in four clades within sub-genotype 3a and were also genetically related to German, Italian, Slovenian, and American HEV sequences. Sub-genotypes 3b and 3j were also found in a single pig each. This study provides the first analysis of the genetic diversity and circulation dynamics of HEV in pigs at slaughterhouses in Serbia.

The aim of this study was to assess the expression of a toxic shock syndrome toxin-1 (TSST-1) gene of Staphylococcus aureus in different types of milk, depending on inadequate temperature and storage conditions. Pasteurized and UHT milk were inoculated with monotoxic TSST-1 strain of S. aureus and growth kinetics was determined by the drop plate method using Baird-Parker agar medium in accordance with EN ISO 6888-1. The patterns of gene regulation were detected by quantitative reverse transcriptase PCR. Relative quantification method for statistical significance testing was used to detect significant gene expression responses. The results of experiments showed the dependence of the growth rate and consequent up-regulation of TSST-1 encoding gene on storage time-temperature and type of milk. In contaminated pasteurized and UHT milk kept at both 15 degrees C and 22 degrees C S. aureus significantly increased its virulent potential over time. This effect was a bit more emphasized in UHT milk serving as a proof of concept. Possible explanation could be a presence of lactic acid bacteria in pasteurized milk which is known to have down-regulatory effect on TSST-1 gene. Maintenance of the milk storage temperature below 8 degrees C and employment of microbiological control measures in hygienic practices, from milk producer through retailer and on to the consumer is of utmost importance to decrease risk of non-emetic staphylococcal poisoning.

For the successful validation and verification of the HACCP system, a food business operator is obliged, among other duties, to have continuous microbiological data of carcasses which are followed by a certain dynamic that the subject himself prescribed. To obtain these data, it is necessary to perform systematic monitoring of indicator microorganisms. The most important meat hygiene indicators are Total Viable Counts (TVC) and Enterobacteriaceae (EC). TVC are defined as indicators of overall slaughter hygiene (equipment, environment, tools, workers), while EC are indicators of faecal contamination on carcasses. The aim of this study was to determine the microbial contamination of cattle and pig carcasses, level of hygiene of the slaughter process as well as whether variations hygiene levels were related to seasonality in Serbia during 2017. The year was divided into four quarters of three months each, while the microbiological results were classified into three levels of hygiene status (unsatisfactory, satisfactory or acceptable). The highest percentage of the results surveyed during the entire study was at a satisfactory hygiene level. Furthermore, we found there were differences in results between the quarters, which could be associated with seasonality. The best microbiological results, and so the best hygiene of carcasses, was recorded in the period April, May, June, while the worst microbiological results were observed in the period of July, August and September.

The aim of this study was to assess the expression of a toxic shock syndrome toxin-1 (TSST-1) gene of Staphylococcus aureus in different types of milk, depending on inadequate temperature and storage conditions. Pasteurized and UHT milk were inoculated with monotoxic TSST-1 strain of S. aureus and growth kinetics was determined by the drop plate method using Baird-Parker agar medium in accordance with EN ISO 6888-1. The patterns of gene regulation were detected by quantitative reverse transcriptase PCR. Relative quantification method for statistical significance testing was used to detect significant gene expression responses. The results of experiments showed the dependence of the growth rate and consequent up-regulation of TSST-1 encoding gene on storage time-temperature and type of milk. In contaminated pasteurized and UHT milk kept at both 15 degrees C and 22 degrees C S. aureus significantly increased its virulent potential over time. This effect was a bit more emphasized in UHT milk serving as a proof of concept. Possible explanation could be a presence of lactic acid bacteria in pasteurized milk which is known to have down-regulatory effect on TSST-1 gene. Maintenance of the milk storage temperature below 8 degrees C and employment of microbiological control measures in hygienic practices, from milk producer through retailer and on to the consumer is of utmost importance to decrease risk of non-emetic staphylococcal poisoning.

For the successful validation and verification of the HACCP system, a food business operator is obliged, among other duties, to have continuous microbiological data of carcasses which are followed by a certain dynamic that the subject himself prescribed. To obtain these data, it is necessary to perform systematic monitoring of indicator microorganisms. The most important meat hygiene indicators are Total Viable Counts (TVC) and Enterobacteriaceae (EC). TVC are defined as indicators of overall slaughter hygiene (equipment, environment, tools, workers), while EC are indicators of faecal contamination on carcasses. The aim of this study was to determine the microbial contamination of cattle and pig carcasses, level of hygiene of the slaughter process as well as whether variations hygiene levels were related to seasonality in Serbia during 2017. The year was divided into four quarters of three months each, while the microbiological results were classified into three levels of hygiene status (unsatisfactory, satisfactory or acceptable). The highest percentage of the results surveyed during the entire study was at a satisfactory hygiene level. Furthermore, we found there were differences in results between the quarters, which could be associated with seasonality. The best microbiological results, and so the best hygiene of carcasses, was recorded in the period April, May, June, while the worst microbiological results were observed in the period of July, August and September.

This study was conducted to investigate the effects of raw material, pork and beef meat, ratio on the physicochemical characteristics of emulsion-type sausage. Five different frankfurter formulations were calculated as follows: B100 (40% beef meat); B75 (30% beef and 10% pork meat); B50 (20% beef and 20% pork meat); B25 (10% beef and 30% pork meat) and B0 (40% pork meat). Frankfurters made solely from beef meat (B100) showed significantly better emulsion stability than those made with pork meat (B0). The increase in the fat content also decreased gel strength, leading to lower values of hardness, cohesiveness, gumminess and chewiness. The optimal ratios between pork and beef meat to enhance the textural properties of frankfurters were B50 and B75. The lightness values (L*) increased with increasing pork meat content, while the redness values (a*) demonstrated the opposite trend. Protein, fat and total pigments displayed a positive relation, whereas water content exhibited a negative relation with a* values.