Lactic acid sprays reduce bacterial pathogens on cold beef carcass surfaces and in subsequently produced ground beef

Organic acids have been shown to be effective in reducing the presence of p athogenic bacteria on hot beef carcass surfaces; however, application for d econtaminating chilled carcasses has not been fully evaluated. In this stud y, a postchill, 30-s lactic acid spray (500 ml of 4% L-lactic acid, 55 degr eesC) was applied onto outside rounds that had been contaminated with Esche richia coli O157:H7 and Salmonella Typhimurium. subsequent to prechill hot carcass treatments consisting of water wash alone or water wash followed by a 15-s lactic acid spray (250 ml of 2% L-lactic acid, 55 degreesC). The pr echill treatments reduced both pathogens by 3.3 to 3.4 log cycles (water wa sh alone) to 5.2 log cycles (water wash and lactic acid). In all cases, the postchill acid treatment produced an additional reduction in E. coli O157: H7 of 2.0 to 2.4 log cycles and of 1.6 to 1.9 log cycles for Salmonella Typ himurium. The counts of both pathogens remained significantly lower in grou nd beef produced from the outside rounds that received prechill and postchi ll acid spray than from those that received a postchill spray only. These d ata Indicate that organic acid sprays may be successfully applied for patho gen reduction in beef carcass processing after the cooler, especially when combined with prechill treatments.