肉的色泽是评价其新鲜与否和品质好坏的重要指标。在宰后成熟过程中，肉色容易受到环境和内在因素的影响而导致褐变。目前对于肉色的研究主要集中于肉色化学方面，但具体的肉色褐变的分子机制仍未探明。因此，本课题将借助蛋白质组学的相关技术，研究牛背最长肌、半腱肌、腰大肌在冷却成熟前后肌浆蛋白质组的变化。首先，通过与肉色基本指标的相关性分析找到与肉色褐变相关的差异蛋白；其次，借助生物信息学的研究方法对相关的差异蛋白进行蛋白相互作用分析、基因本体论注释及代谢通路分析；最后，使用定量蛋白质组学研究技术对与肉色密切相关的差异蛋白进行绝对定量。此外，研究肉色相关的重要代谢物含量的变化，结合蛋白质组学的研究结果，期望找出和肉色相关的潜在生物标记物，为揭示肉色褐变相关分子机制提供理论依据。

Meat color is an important indicator that helps evaluate the freshness and the quality of the meat. During the process of post-mortem aging, meat color is susceptible to impacts of the environmental and internal factors, leading to discoloration of meat. At present, the investigations mainly focus on meat color chemistry, however, the specific molecular mechanisms concerning meat discoloration are still unclear. Thus, the aim of this project is to utilize proteomics to study the changes in sarcoplasmic proteome of bovine longissimus lumborum, semitendinosus and psoas major during post-mortem aging process. First of all, the differentially expressed proteins will be identified and correlated with the physicochemical indices of meat color. Secondly, by means of bioinformatic approaches, pathway analysis, protein-protein interaction analysis and gene ontology analysis of differentially expressed proteins will be carried out. Eventually, quantitative proteomics will be employed in the abosolute quantification of differentially expressed proteins correlated with meat color. In addition, the metabolites that are related to meat color will be investigated as well. The research results of the metabolites combined with proteomics will be conducive to discovery of potential biomarkers and elucidation of related molecular mechanisms involved in the meat discoloration.