The hygienic and organoleptic qualities of ground beef prepared from manufacturing beef pasteurized by immersion in hot water

Groups of 24 lots of manufacturing beef were untreated or treated by immersion in,rater of 85 degrees C for 15 s or 1 min. Each lot was ground, and total counts, coliforms and Escherichia coli were enumerated in samples from each ground lot. Each ground lot was divided into two portions, and their appearances were assessed by a panel 2, 24 and 48 hr after the treatment of the beef. Treatment for 15 s reduced the numbers of non-thermotolerant bacteria, including coliforms and E. coli, by about one order of magnitude. Treatment for 1 min reduced the numbers of non-thermotolerant bacteria by about two orders of magnitude, with reduction of the numbers of coliforms and E. coli in all samples to below the detection level of 1 CFUg(-1). Ground beef prepared from treated product tended to appear lighter in colour and duller than ground beef from untreated product, and to be more discoloured after 24 hr. However, the changes in the appearances of ground beef resulting from the treatment of manufacturing beef were small, and seemingly would not render the ground meat unacceptable for retail display. In a triangle taste test, there was no significant difference (p > 0.05) in the flavour of hamburger patties prepared from untreated beef or from beef treated for 1 min at 85 degrees C. The findings suggest that pasteurization of manufacturing beef could be a commercially useful technique for reducing the risk of infection with enteric bacteria to consumers of mass produced hamburger patties. (C) 1997 Elsevier Science Ltd.