Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/3/2001
Publication Date: 12/20/2001
Citation: Castelo, M.M., Koohmaraie, M., Berry, E.D. 2001. Microbial and quality attributes of ground pork prepared from commercial pork trim treated with combination intervention processes. Journal of Food Protection. 64(12):1981-1987. Interpretive Summary: Carcass antimicrobial treatments are commonly used in the meat industry to reduce the possibility of pathogen contamination. However, during the process of cutting the carcass into individual cuts of meat, recontamination can occur. Thus, applying antimicrobial treatments to trimmings provides an additional means to reduce bacterial contamination prior to grinding, thereby further reducing the probability of the presence of pathogenic bacteria in the final ground product. In addition, processes that involve the combination of antimicrobial treatments may give greater reduction of bacteria than would the separate, individual treatments. However, it is important that such treatments not affect product quality attributes. These experiments examined the ability of combination antimicrobial treatment processes of lean pork trimmings to reduce fecal bacteria populations in ground pork prepared from those trimmings, and also examined the effects of the processes on the color and processing quality of the ground pork. The combination processes included high pressure water washes, 2% lactic acid washes, and/or hot air treatments. Those processes that included lactic acid washes were the most effective at both reducing the numbers of fecal bacteria in the ground pork and suppressing their growth during refrigerated storage for 21 days. However, the process that included the use of both lactic acid and hot air was detrimental to the color and processing quality of the ground pork. The process that combined water and lactic acid provided the greatest microbial reduction and growth suppression without large negative effects on the quality attributes of the ground pork.
Technical Abstract: Effects of combination treatment processes of commercial pork trim on the microbial and quality attributes of the subsequent ground pork were examined. Fresh commercial pork trim inoculated with swine feces was subjected to five different intervention treatments: (1) control, (2) water (W, 15 deg C, 120 s), (3) W followed by 2% lactic acid wash (W+LA, LA: 15 deg C, 75 s), (4) Combination 1 (Comb 1; W+LA+hot air [HA, 510 deg C, 90 s]), and (5) Comb 2 (HA+W+HA). Following treatment, the pork trim was ground, vacuum packaged and stored at 4 deg C for 21 days. Populations of aerobic bacteria, coliforms, Escherichia coli, and lactic acid bacteria were monitored before treatment, after treatment (day 0), and at 2, 7, 14 and 21 days. In addition, uninoculated pork trim was treated as described above and the color and emulsion stability of the ground product was evaluated. Ground pork prepared from trim treated with any of the processes had lower initial microbial populations as compared to the untreated samples. W+LA and Comb 1, which included LA, were more effective than W and Comb 2 at both reducing initial populations and suppressing the growth of aerobic bacteria, coliforms, and E. coli in ground pork during refrigerated storage. By day 21, populations of aerobic bacteria in ground pork prepared from control, W-, and Comb 2-treated trim were 8.22-8.32 log10 CFU/g, but in W+LA and Comb 1 ground pork were 6.32 and 4.90 log10 CFU/g, respectively. Among trim interventions examined, Comb 1 was most detrimental to the color and emulsion stability of ground pork. W+LA treatment provided the greatest microbial reduction and inhibition without large negative effects on quality attributes of the ground pork.