Effect of stress associated to different storage conditions on species diversity and microbial metabolites in beef as evaluated by pyrosequencing, PCR- DGGE, SPME-GC/MS and 1HNMR

摘要

Beef chops were stored at 4℃ in four different conditions: (i) air (A), (ii) modified atmosphere packaging (MAP), (iii) vacuum packaging (V), (iv) bacteriocin-activated antimicrobial packaging (AV). After 0 to 45 days of storage analyses were carried out to determine viable counts of spoilage-associated microbial populations; microbial metabolites by SPME-GC/MS and 1HNMR; microbial diversity by PCR-DGGE and pyrosequencing. The microbiological shelf-life of meat increased with increasing selectivity of storage conditions. A and MAP allowed shorter lag times for most of the microbial groups compared to storage in V and AV conditions. The culture-independent analysis of DNA directly extracted from meat by pyrosequencing showed that Ralstonia sp., Limnobacter sp. and B. thermosphacta were the most abundant species occurring in the meat at time zero.