Antimicrobial Ice-based Novel Meat Grinder Sanitation Process

Introduction: An estimated 60% of all retail beef sales are in the form of ground beef.  There are existing protocols and control points in meat processing, which specify the frequency and proper procedures for grinder sanitization.  Current industry protocol is to disassemble and then clean meat grinders at the end each shift.  However, if contamination occurs between two cleaning operations, large amounts of the product could be contaminated and subject to recall.  

Purpose: This study was designed to develop a rapid intervention step to sanitize meat grinders without disassembling them.   

Methods: Meat grinders were contaminated by processing 500 g beef trims spiked with either 3 or 6 log CFU/g E. coli O157: H7.  After contamination, 600 g peroxyacetic acid ice (300 mg/L) along with 500 ml peroxyacetic acid solution (300 mg/L) were processed through meat grinders to inactivate pathogen.  After antimicrobial ice treatment, two 250 g uninoculated beef pieces were ground and collected to determine transfer of pathogens from meat grinder to ground beef samples.  Six hundred g deionized water ice with 500 ml deionized water treatment (DI ice), and no treatment controls were used in this study.  Each experiment was repeated at least five times.  

Results: When grinders were inoculated with low levels of pathogens, antimicrobial ice treatment completely eliminated E. coli O157: H7 cross-contamination.  While DI ice and no treatment control yielded a significantly higher (P < 0.05) pathogen recoveries; 1.98± 0.31 and 2.82± 0.26, respectively.  Antimicrobial ice treatment of meat grinders inoculated with higher levels of pathogens yielded recoveries of 1.60±0.42 log CFU/g E. coli O157: H7 in the ground beef.  Which is significantly lower than DI ice (3.48±0.18 log CFU/g) and no treatment control (4.79± 0.41 log CFU/g)) recoveries (P < 0.05).    

Significance: This novel method could provide a rapid alternative to the traditional meat grinder sanitation process.