抄録
In our previous paper, it was reported that cysteamine (CysA) in fresh sardine meat reacted with formaldehyde (FA) in the meat to form thiazolidine which may act as a precursor of nitrosothiazolidine (NTHZ) in fish meal. CysA is known to react with various carbonyl com-pounds including FA to form thiazolidine derivatives. Several types of carbonyl compounds have been reported to exist in dried sardines. In the present study, a survey was conducted on the distribution of notrosated thiazolidine dirivatives in fish meal samples. The presence of N-nitroso-2-methylthiazolidine (NMTZ) could be confirmed in three commercial fish meal sam-ples and also in the test meal samples after being treated with gaseous NO2. In the case of test meal samples, it was found that the yield of NMTZ apparently increased with the storage periods of raw materials at 10°C, and the changes in NMTZ contents were almost propor-tional to the levels of acetaldehyde in meal samples. The above-mentioned results indicate that acetaldehyde in the fish material would play an important role in the formation of NMTZ in fish meals.
