Investigation of Biogenic Amines in Dried Bonito Flakes from Different Countries Using High-Performance Liquid Chromatography

Dried bonito flakes are used as a popular food ingredient worldwide due to their special umami flavor; however, little knowledge exists regarding their biogenic amines and secure content, as related research have not been conducted. Based on this, we investigated the biogenic amines content of dried bonito flakes using reversed-phase high-performance liquid chromatography (RP-HPLC) methods that incorporate UV detection. We chose 22 samples from Japan, Taiwan, the Philippines, and China (in Zhejiang, Fujian, Guangdong, Shanghai, Jiangsu provinces). This method can effectively separate eight types of biogenic amines (tryptamine, beta-phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine, and spermine). The correlation coefficient of this method was higher than 99%, and the limits of detection were determined to be between 0.10 and 0.70 mu g/L. The average recovery of the eight biogenic amines ranged from 81.49 to 97.99%; relative standard deviations were below 4%. This high recovery rate indicated that the method can accurately determine the biogenic amines within dried bonito flakes. Additionally, this method does not require purification of the sample, and the derivation is simpler than that of other methods. Using this method, the main amines found in dried bonito flakes were histamine, tyramine, and spermidine, and the detection rate was 100%. The maximum amount of histamine detected from samples from the Philippines was 1532 mg/kg, and the minimum was 18 mg/kg. The concentration of histamine in the dried bonito flakes was above the FDA safe standard limit for fish and fishery products. Based on this, the dried bonito flakes appear to be harmful to humans.