外源氨基酸对牡蛎肽美拉德反应产物风味特性的调控作用

为改善牡蛎肽美拉德反应产物腥味浓、鲜香味不足的问题，基于牡蛎肽-半胱氨酸-木糖体系，借助感官评定明确了外源氨基酸对其气味与滋味特性的影响，结合挥发性风味物质的组成、整体气味轮廓以及肽相对分子质量分布剖析了风味差异的原因。结果表明，与单一添加甘氨酸或谷氨酸相比，复合添加这两种氨基酸对牡蛎肽美拉德反应产物的去腥增香具有更理想的效果。甘氨酸和谷氨酸的协同作用显著降低了庚醛、辛醛等关键腥味化合物对整体气味属性的影响，挥发性风味成分的种类增加至21种，从而提高了整体香气的丰富性。与此同时，复合添加外源氨基酸促进了美拉德反应过程中牡蛎肽的降解，提高了相对分子质量小于1 000的呈味肽的比例，进而改善了体系的滋味品质。该研究可为调控牡蛎调味料风味品质提供科学依据。

Flavor Characteristics of Oyster Peptide Maillard Reaction Products Regulated by Exogenous Amino Acids

In order to improve the strong fishy smell and insufficient fresh fragrance of oyster peptide Maillard reaction products (MRPs), the effects of exogenous amino acids on the odor and taste characteristics were explored by means of sensory evaluation based on oyster peptide-cysteine-xylose system. The causes of flavor differences were analyzed with the combination of the composition of volatile flavor compounds, the overall odor profile and the relative molecular weight distribution of peptides. The results showed that compared with the addition of glycine or glutamic acid alone, the addition of the two amino acids effectively removed fishy smell and enhanced aroma of oyster peptide MRPs. In addition, the synergistic effect of glycine and glutamic acid significantly reduced the impact of key fishy compounds, such as heptanal and octanal, on the overall odor properties, while the types of volatile flavor components increased to 21, which improved the richness of overall aroma. Meanwhile, the compound addition of exogenous amino acids promoted the degradation of oyster peptides during the Maillard reaction and increased the proportion of flavor peptides with relative molecular weight less than 1 000, which enhanced the taste quality of the system. This study could provide scientific basis for regulating the flavor quality of oyster seasoning.