51A-38

M. SUGANO¹, H. C. Lee¹, and E. S. Tjong². (1) Food and Nutrition, California State University, Long Beach, CA, 800 W. First St. #1706, LA, CA 90012, (2) Technical Service, Red Chember Co., 1912 E. Vernon Ave., Vernon, CA 90058

Sushi is becoming more popular in America. Generally, seafood is very safe to eat; however, it is the most perishable of fresh foods. Many people are afraid of consuming raw fish for fear of bacterial growth, parasites, and poor sanitation. The first objective was to evaluate the microbiological safety of raw fish served at Japanese restaurants by bacterial and parasite tests in sashimi, and by testing the cleanness of serving equipment and foodhandlers' hands. The second one was to evaluate the antibacterial effects of wasabi and vinegar. This study evaluated the microbiological safety of raw fish served at 20 Japanese restaurants in Long Beach and its vicinities. Bacterial growth was evaluated by three indicator microorganisms. Parasite analyses were done by nondestructive methods with ultraviolet light. Swab tests (cutting boards, knives and foodhandlers' hands) were conducted to evaluate the cleanness, and the same microbiological tests were conducted. Four different combinations of sushi from each restaurant were tested to evaluate the antibacterial effects of vinegar and wasabi. Aerobic plate counts were below the FDA guidance level (ranging from 5x10⁵ to 10⁷ bacteria/g) and S. aureus and E. Coli were within guidelines. The pH of raw fish ranged from 5.7 to 6.4. No parasites were detected. For swab tests, 40% of the cutting boards tested and 10% of the knives tested were rather high in aerobic plate count. Vinegar substantially lowered the pH of the sushi (pH 4.7 to 5.9) compared to the pH without vinegar (pH 5.5 to 6.2). Bacteria counts of some sushi using vinegar and/or wasabi were lower than those of sushi without vinegar and wasabi. These results suggest that consuming raw fish at Japanese sushi restaurants is relatively safe. Vinegar and wasabi play an important role of reducing some bacteria in sushi.