Irradiation and organic acid treatment for microbial control and the production of biogenic amines in beef and pork

The effect of irradiation and organic acid treatment in controlling the growth of microorganisms and the formation of biogenic amines (BAs) in ground beef and pork was studied. Bacillus cereus, Enterobacter cloacae, and Alcaligenes faecalis were inoculated into the ground beef and pork with approximately 107 CFU/g. A gamma irradiation was used with absorbed doses of 0, 0.5, 1, and 2 kGy, as irradiation treatment and 2 M solutions of acetic, citric, and lactic acid were used as organic acid treatment. Irradiation was effective in reducing the inoculated bacteria and achieved about 3 decimal reductions by 2 kGy. The levels of putrescine, tyramine, spermine, and total amount of biogenic amines were significantly reduced by irradiation of ground beef and pork inoculated with different microorganisms tested. On the other hand, organic acid treatment showed only 2 decimal reductions or less. The reduction of the BAs content was also limited and variable by organic acid treatment. Therefore, the results indicate that, for the controlling of microorganisms and production of biogenic amines in ground beef and pork, irradiation was more effective than organic acid treatment.