金华火腿苦味肽形成途径及其呈味机理研究

金华火腿风味强烈深受消费者喜爱，但苦味缺陷严重降低了产品感官品质。申请人前期研究发现，金华火腿苦味缺陷形成与肌肉蛋白的强烈降解密切相关，然而造成苦味缺陷的苦味肽形成途径及其呈味效应机制尚待明确。本项目基于缺陷火腿的感官特性，采用感官评定结合多肽组学筛选和识别特征苦味肽，并构建肽指纹图谱；通过蛋白组学和酶活性分析评估母蛋白的降解过程和降解位点，探讨何种蛋白酶起主导作用；借助同源建模、分子对接和分子模拟，剖析苦味肽与受体蛋白的结合方式及结合位点；采用HEK-293T细胞模型解析苦味肽介导的苦味信号转导途径。本项目的实施有利于提高我们对苦味肽形成机制和苦味效应理论的认知，从而为未来主动调整工艺设计，降低苦味缺陷火腿发生率提供理论依据。

Jinhua ham is very popular among consumers due to its rich taste and strong aroma. However, the bitterness defect reduces sensory quality of Jinhua ham. Previous studies of applicant have demonstrated that the formation of bitterness defect in Jinhua ham is closely related to the intense degradation of muscle proteins. However, the formation pathway and taste mechanism of bitter peptides that cause the bitterness defect of Jinhua ham are not yet clarified. Based on the sensory characteristics of defective ham, sensory evaluation combined with peptidomics will be employed to screen and identify characteristic bitter peptides, and to construct peptide fingerprinting in this project. Proteomics and enzyme activities analyses will be used to evaluate the degradation of parent proteins and their cleavage sites, and to explore which protease plays a key role in degrading these parent proteins. The binding mode and binding sites of the interaction between bitter peptides and receptor proteins will be analyzed by homology modeling, molecular docking and molecular dynamics simulation. The signaling pathway mediated by bitter peptides will be further investigated using HEK-293T cell model. The implementation of this project is conducive to improving our understanding of the formation mechanism of bitter peptides and the theory of bitter effect, and to providing a theoretical basis for actively adjusting the process design and reducing the incidence of bitterness defect in Jinhua ham in the future.