Inoculation of Beef Steaks with Lactobacillus Species Before Vacuum Packaging. II. Effect on Meat Quality...

Biceps femoris steaks (n = 432) were inoculated with each of four Lactobacillus sp. (atypical streptobacteria and betabacteria) at a high or low level of cell concentration, vacuum-packaged, stored for up to 35 days at 1-3 C, displayed under retail conditions for 3 days and subsequently cooked for sensory panel analysis. Although there was some evidence that use of high level, rather than low level or no, inoculation with Lactobacillus cultures resulted in the lowest muscle surface pH and the brightest muscle color, the least surface discoloration and the highest overall appearance ratings following storage for 0-35 days, there were negative effects which negated efficacy of high level inoculation. Negative effects of use of high level, rather than low level or no, inoculation with Lactobacillus cultures included the highest incidence of off-odor, the highest incidence of defects during retail display (most extensive surface discoloration, most extensive peripheral discoloration, least desirable overall appearance) and the lowest palatability (juiciness, tenderness, flavor and overall palatability) ratings. Few of the differences among steaks were statistically significant but the preponderance of evidence (largely that based on numerical differences) suggests that inoculation with the Lactobacillus cultures used in this study will not improve storage life, retail caselife or palatability of beef.