Growth and Volatile Compounds of Escherichia coli O157:H7 on Irradiated Pork

The growth kinetics and volatile compounds of Escherichia coli O157:H7 on irradiated, cubed raw pork were investigated in this study. The results showed that the Gompertz model fitted the growth data of E. coli O157:H7 on pork with high R-2 value, and the growth kinetic parameters exhibited respective features at different temperature and inoculum levels. For the volatile metabolites production of E. coli O157:H7, distinct variations occurred after the middle logarithmic phase of bacterial growth. Indole showed a rapid and obvious increase at the onset of the static phase; 2-heptanone, 2-nonanone and 2-tridecanone followed the trend of bacterial growth with lag, logarithmic and static phases; the signal intensities of 1-hexanol and 1-octanol increased at the logarithmic phase and decreased at the static phase. Practical ApplicationsThe relationship between growth and volatile production of E. coli O157:H7 on raw pork would provide some fundamental scientific data for the emerging odor inspection technique.