2021 Volume 28 Issue 2 Pages 98-106
A rapid and simple method was developed for the determination of emetic toxin (CER; cereulide) produced by Bacillus cereus in processed foods. CER was extracted using 70% hydrated acetonitrile and n-hexane. The n-hexane layer was separated and evaporated. The residue was redissolved in acetonitrile and defatted with n-hexane saturated with acetonitrile, and The acetonitrile layer was then analyzed using LC-MS/MS. To validate this method, foods that cause food poisoning by B. cereus, including cooked rice, fried rice, pilaf, and pasta, were spiked with 1 ng/g or 100 ng/g CER, and recovery test were performed. CER recovery rates from these 4 processed foods were 75%–92% at 1 ng/g, and 70%–91% at 100 ng/g with satisfactory repeatability and all other parameters. It was possible to detect CER in fried rice about 6 hours after inoculation with B. cereus.
