Top and bottom round steaks inoculated with Yersinia enterocolitica were stored vacuum packaged and in polyvinyl chloride (PVC) films at 1, 2.5 and 5°C for 21–35 days. Y. enterocolitica and total aerobic plate counts of steaks were consistently higher in the more oxygen permeable film (PVC) than in the vacuum packages. The microbial flora of the vacuum packaged steaks at the end of the storage period (21–35 days) consisted, in addition to Y. enterocolitica, primarily of Lactobacillus spp., that of the steaks stored in PVC of Pseudomonas