P2-22 Effects of Boning Time on Bacterial Load of Horse Meat

Tuesday, July 11, 2017
Exhibit Hall (Tampa Convention Center)
Brian Walker , University of Alberta , Edmonton , Canada
Heather Bruce , University of Alberta , Edmonton , Canada
Lynn McMullen , University of Alberta , Edmonton , Canada
Introduction:  The global horse meat market averages 700,000 tonnes per year with the majority being consumed in European and Asian countries. Canadian meat regulations require that the warmest part of a carcass reaches an internal temperature of 7°C prior to boning; however, no scientific data on the impact of early harvest on the microbiology of horse meat is available.

Purpose: To evaluate the impact of boning time on the total aerobic bacteria, lactic acid bacteria, and Enterobacteriaceae on horse meat.

Methods:  Horse carcass sides (>180kg; n=36) were chilled for 17, 26, or 30 h prior to boning. After chilling, the semimembranosus muscles were harvested from the right side. The entire surface (1036 cm2) of the muscle was swabbed and enumerated for total aerobic bacteria, lactic acid bacteria and Enterobacteriaceae. Muscles were cut into steaks, vacuum packaged and stored for up to 90 days at 0°C. At regular intervals steaks were removed for microbial analysis. Mean log CFU/cm2 were analyzed with ANOVA.

Results:  The time of boning had no effect (P>0.05) on the total aerobic, lactic acid bacteria, or Enterobacteriaceae when boned at 17, 26, or 30 h. Total aerobic counts were 1.6±0.4, 1.5±0.4, and 1.7±0.4 log CFU/cm2, lactic acid bacteria were 0.3±0.5, -0.4±0.7, and 0.0±0.5 log CFU/cm2, and Enterobacteriaceae were -2.2±1.2, -1.7±1.4, and -1.5±1.4 log CFU/cm2, respectively. Numbers are extremely low due to the large surface area that was swabbed. During storage numbers of organisms decreased initially and then increased during storage. Cell counts only reached a maximum of three log CFU/cm2 after 90 days of storage.

Significance:  Shorter chill times had no adverse effects on the hygienic condition of horse meat allowing horse meat to be harvested at a higher internal carcass temperature without compromising microbial quality and storage life.