Effects of muscle alpha-tocopherol level and surface microbiological contamination on retail caselife of fresh beef from the US, Japan and Australia

This study evaluated effects of dietary supplementation of vitamin E (1000 IU vitamin E/daily for 100 days prior to harvest) to fed cattle on retail c aselife performance of fresh US beef in an export market (Japan). Economic performance (monetary losses associated with color deterioration) for US be ef from vitamin E supplemented cattle vs beef from non-vitamin E supplement ed cattle was contrasted. An additional, controlled study was performed to compare muscle alpha-tocopherol concentrations, color changes and microbiol ogical growth for fresh beef derived from vitamin E supplemented US cattle and fresh beef from cattle with an unknown history, but from other countrie s. Australian strip loin steaks had the highest muscle alpha-tocopherol con centrations (4.6 mu g/g tissue), followed by US strip loin steaks derived f rom vitamin E supplemented cattle (3.4 mu g/g tissue) and Japanese strip lo in steaks (2.8 or 2.5 mu g/g tissue). US strip loin steaks from non-vitamin E supplemented cattle had the lowest (p < 0.05) alpha-tocopherol levels (1 .7 mu g/g tissue). Aerobic plate counts and total coliform counts were gene rally low at 0 days of retail display, and they changed similarly among tre atments over 6 days of display, regardless of the country of origin of the beef. Vitamin E supplementation of US cattle reduced total Japanese retail store losses due to discoloration of US beef, in yen, by 5.2 percentage poi nts (p < 0.05), saving Japanese retailers US $0.24/kg. Data suggest that US beef-normally perceived, in Japan, to discolor more quickly in the retail display case than beef from Australia-would compete more favorably, in shel f-life, with beef from other countries if it was derived from cattle that h ad been fed supplemental vitamin E. (C) 1999 Elsevier Science Ltd. All righ ts reserved.