Monitoring and risk assessment of biogenic amines in commercial Thua-Nao, a traditional Northern Thai fermented soybean paste

Abstract

Thua-Nao, a traditional fermented soybean product in Thailand, is susceptible to contamination with biogenic amines (BAs), thus increasing the risk to human health. The present study evaluated the contamination, formation, and risk assessments of BAs in two types of Thua-Nao. The elution conditions were optimized and used to analyze thua nao BAs with good correlation coefficients and high recovery. The average total BA content in dried Thua-Nao (D-TN; 342 mg/kg) was greater than that in fresh Thua-Nao (F-TN; 239 mg/kg), but the difference was not significant. Tyramine (TYM) was the dominant BA in thua nao, accounting for more than half of the total BAs in the majority of the samples, and it also exhibited a significant positive correlation with soluble protein and total BAs. The calculated highest estimated daily intake (EDI) and index of food safety (IFS) of TYM were 1.51 μg/kg/day and 0.008, respectively, among the age groups who consumed thua nao, indicating a low risk to human health. However, the acute risk index of TYM in F-TN and D-TN among patients taking monoamine oxidase inhibitors (MAOIs) was greater than 80 %. Thus, these results suggested that an adverse health effect is unlikely for the general population after excessive consumption of TYM-contaminated Thua-Nao, but it may have serious health implications for patients taking MAOIs.