Food Safety Focus (109th Issue, August 2015) – Food Incident Highlight

Microbiological Quality of Sushi and Sashimi

Last month, the Centre for Food Safety (CFS) released the report on the microbiological quality of sushi and sashimi. Whilst none of the 197samples had any food safety problems, four were found unsatisfactory regarding the hygienic indicators.

Proper acidification of cooked rice to pH4.6 or below is known to inhibit the growth of pathogenic bacteria, particularly Bacillus cereus. The sushi rice of all but two samples was at pH 4.6 or below.

The CFS advises people with weakened immunity, the elderly, pregnant women and young children who are at higher risk for foodborne illnesses to avoid eating sashimi or sushi with raw or undercooked ingredients. The CFS also urges the trade to observe the Microbiological Guidelines for Food and to keep sushi and sashimi at 4°C or below, and to discard the sushi displayed at above 4°C for over four hours. Food handlers are advised to check the pH value of acidified rice with the aim to achieve a pH value of 4.6 or below.

Some tools for measuring pH of sushi rice