Predictive Modeling of the Shelf-Life of Chilled Pork at Different Temperatures

This study was designed to establish a predictive model for the shelf-life of chilled pork with specific spoilageoorganisms.Pork leg muscles were washed with 80 ℃ sterile water,inoculated with Aeromonas spp.,sealpackaged,and stored at 0,4,7,15 or 20 ℃.The values of pH,TVBN and TBA and total viable count were determined during storage at the different temperatures.Besides,sensory evaluation was carried out.The resulting data were analyzed with the software Origin 8.0.The results show that the growth dynamics of A.spp.in chilled pork could be well fitted with a modified Gompertz model.Temperature effect on maximum specific growth rate and lag phase was described by the rootmean-squares(B lehradek) model as a good linear relationship with R2 values of 0.93 and 0.95,respectively.At the end of organoleptic shelf life,the average logarithmic value(lg NS) of A.spp.number(CFU/g) in pork samples stored at 0,4,7,15 or 20 ℃ was(6.33 ± 0.14)(lg(CFU/g)),and the average value of lg Nmax was(7.36 ± 0.21)(lg(CFU/g)).A shelf life(SL) model for chilled pork stored at 0–20 ℃ was established as follows: SL = [1/(0.026T-0.00048)2]-[(7.36-lgN0)/2.718 ×(0.0102T + 0.148)2] × {ln[-ln(6.33-lgN0)/(7.36-lgN0)]-1}.The model was validated by observing the actual shelf-life of pork at 8 ℃ and 12 ℃.The relative errors between the actual and predicted shelf-lives at 8 ℃ and 12 ℃ were both below 10%,suggesting that the predictive model was effective in predicting the shelf-life of chilled pork stored at 0–20 ℃.