Abstract:

The sensory index, total volatile base nitrogen (TVB-N) value, total number of bacteria and spoilage bacterial
flora in fresh pork stored at 4 and 25 ℃ were investigated to discover the critical point of spoilage and to determine its shelf
life. The correlations between quality parameters related to spoilage and spoilage bacteria were analyzed and described by
Pearson correlation coefficient. The results showed that the fresh pork stored at 4 and 25 ℃ displayed significant changes in
sensory index after 96 and 24 h of storage, respectively. The TVB-N values were (19.28 ± 0.22) and (20.14 ± 0.21) mg/100 g,
and bacterial count were (8.11 ± 0.29) and (7.91 ± 0.23) (lg(CFU/g)), respectively. There were remarkable relationships
between Pseudomonas spp. and the total number of bacteria or TVB-N values, with Pearson correlation coefficient of 0.955
(P < 0.01) and 0.901 (P < 0.01) at 4 ℃, respectively. At 25 ℃, there were remarkable relationships between Enterobacteriaceae
and the total number of bacteria or TVB-N values, with Pearson correlation coefficient of 0.914 (P < 0.01) and 0.871 (0.01 <
P < 0.05), respectively. These results demonstrated that the shelf life of fresh pork stored at 4 and 25 ℃ were 96 and 24 h,
respectively. There was consistency between sensory index and TVB-N values or total number of bacteria at the end of shelf
life. The main spoilage bacteria in fresh pork stored at 4 ℃ were Pseudomonas spp. and Enterbacteriaceae at 25 ℃.

Key words: pork, total volatile base nitrogen (TVB-N), spoilage bacteria, total bacterial count