氨基甲酸乙酯是发酵食品中广泛存在的“2A”类致癌物，可由氨甲酰化合物和乙醇反应生成。葡萄汁中的氨基酸经酿酒酵母的氮代谢后，可生成氨甲酰化合物，进而形成氨基甲酸乙酯。为了研究氨基酸与葡萄酒中氨基甲酸乙酯的关系，本文构建了氨基酸缺失的模拟葡萄汁，比较了他们和正常模拟葡萄汁经主发酵后的氨基甲酸乙酯和尿素含量，并采用N15同位素示踪确认了氨基酸对氨基甲酸乙酯的贡献。结果表明：磷酸氢二铵单独作为氮源发酵不会产生氨基甲酸乙酯，用其替代缺失的氨基酸不会影响正常发酵过程；缺失精氨酸的模拟葡萄汁发酵后，尿素和氨基甲酸乙酯含量明显减少，而缺失其它氨基酸对二者无显著影响。N15同位素示踪证明精氨酸胍基的氮原子参与了氨基甲酸乙酯的合成。本文为发酵食品危害物的前体挖掘提供了新的思路，也为气质联用仪辨识同位素提供了方法借鉴。

Ethyl carbamate, a type 2A carcinogen, widely exists in fermented foods and is generated by the reaction of carbamyl compounds and ethanol. The amino acids in grape juice are transformed to carbamyl compounds via the nitrogen metabolism of Saccharomyces cerevisiae and in turn form ethyl carbamate. To examine the relationship between amino acids and ethyl carbamate in wines, this study used a simulated grape juice lacking amino acids and compared its ethyl carbamate and urea content with that in normal simulative grape juice after fermentation. In addition, an N15 isotope tracer was used to confirm the contribution of amino acids in the formation of ethyl carbamate. The results showed that as the sole nitrogen fermentation source, diammonium phosphate could not generate ethyl carbamate and did not affect the normal fermentation process when it replaced the missing amino acids. Furthermore, urea and ethyl carbamate contents decreased significantly in the arginine-lacking simulated grape juice after fermentation, whereas the lack of other amino acids had no significant effect on this measure. N15 isotope tracing proved that the guanidine nitrogen atoms of arginine were involved in ethyl carbamate synthesis. The results of this study provide a new direction for mining the precursor of hazardous substances in fermented foods.

国家自然科学基金资助项目 (31101275，31201354 )