Correlations between growth parameters of spoilage micro-organisms and shelf-life of pork stored under air and modified atmosphere at -2, 4 and 10 degrees C.
The correlations of the growth parameters (the initial cell number (N(0)), maximum cell number (N(max)), maximum specific growth rate (mu(max)), lag-phase (lambda)) of typical spoilage micro-organisms (lactic acid bacteria (LAB), coliforms, pseudomonads, Brochothrix thermosphacta) growing on sliced pork to the sensory shelf-life and microbial shelf-life were investigated. The changes in sensory quality and proliferation of micro-organisms on pork shoulder were studied at different atmosphere conditions (air and 40%CO(2)/59%N(2)/1%O(2)) and temperatures (-2, 4 and 10 degrees C). Microbial counts were fitted to the modified-Gompertz equation to obtain the growth parameters of different micro-organisms. B. thermosphacta and coliforms were predominant bacteria associated with spoilage of pork under all temperatures and air conditions. However, pseudomonads could only dominate under regular atmosphere condition. Using multiple linear regression, high correlations were found between the lag-time (lambda) of LAB (0.9814, 0.9830), B. thermosphacta (0.9895, 0.9849), or the maximum specific growth rate (mu(max)) of coliforms (-0.9583, -0.9695) and the microbial shelf-life and sensory shelf-life, respectively. The mu(max) and lambda of micro-organisms correlated well with microbial and sensory shelf-life. The shelf-life of pork is mainly correlated with the growth parameters of mu(max) and lambda than by N(max).
Liu
Fang
F
Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai Qi Xin Road 2678, Shanghai 201101, China.
Yang
Run-Qing
RQ
Li
Yun-Fei
YF
D000818:Animals; D001419:Bacteria / Q000254:growth & development*; D002245:Carbon Dioxide / Q000378:metabolism; D003258:Consumer Behavior; D003257:Consumer Product Safety; D005506:Food Contamination / Q000032:analysis*; D018857:Food Packaging / Q000379:methods*; D005519:Food Preservation / Q000379:methods*; D006801:Humans; D016014:Linear Models; D008461:Meat Products / Q000382:microbiology* / Q000592:standards; D008954:Models, Biological; D009584:Nitrogen / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D013552:Swine; D013649:Taste; D013696:Temperature; D014618:Vacuum
D002245:Carbon Dioxide; D009584:Nitrogen; D010100:Oxygen