基于线粒体蛋白质组研究不同极限pH值牛肉成熟期间肉色变化机制

不同极限pH值的牛肉颜色差异显著，高pH值的DFD牛肉，因其外观呈现紫黑色给肉类行业带来很大的经济损失。这一劣变的肉色在成熟期间能否得到改善、不同极限pH值牛肉在成熟期间的肉色变化机制亟待阐明。已有研究初步表明肉色变化与线粒体有关，但相关的关键酶及代谢通路尚未确定。因此，本课题拟以线粒体中的蛋白质组为研究对象，利用蛋白质组学确定不同极限pH值牛肉(5.4-5.8;5.8-6.1; >6.1)在成熟0-21天的线粒体差异蛋白；同时对应测定不同极限pH值牛肉的肉色、肉色货架期及肉色稳定性等肉色生物化学指标在成熟期间的变化规律；通过分析肉色指标与差异蛋白表达的相关性，结合蛋白质功能分析、亚细胞定位及代谢通路分析(KEGG)，确定与肉色相关的线粒体代谢路径和关键线粒体酶类。能够从线粒体蛋白质水平上阐述不同极限pH值牛肉成熟期间肉色变化的机制，为肉色劣变的控制、护色技术的开发提供理论依据。

The color is significant different between various ultimate pH beef. Typically, the DFD beef with high ultimate pH, shows up a very dark color, which has brought a large economic loss for the beef cattle industry. However, whether the dark color would be getting better, and how the different ultimate pH beef keep the color stability during ageing are current questions for the researchers to answer. Previous studies showed mitochondria probably related to beef color stability, but the related key enzymes and metabolism pathways are not yet determined. Thus, mitochondrial proteome analysis will be applied in this study to detect the differential mitochondrial proteins among the three ultimate pH beef (5.4-5.8, 5.8-6.1 or greater than 6.1) groups during ageing within 21 days. And the traditional biochemical meat color analysis will be also applied to determine the color, color shelf-life and color stability of those different types ultimate pH beef. Afterwards, the correlation between the biochemical indices and the expression of differential proteins will be analyzed, to determine the key mitochondrial enzymes involved in the color development during ageing. Finally, the metabolism pathways related to the maintenance of beef color stability during ageing will be predicted based on the bioinformatics, such as Gene Ontology, Protein subcellular localization and Kyoto Encyclopedia of Genes and Genomes. The information generated from this research will explain the mechanisms of the development of beef color with different ultimate pH during ageing from the mitochondrial proteome perspective. And in the practical sense, it will provide a theoretical basis for controlling the poor color beef, especially the DFD beef, and promote more color-sustaining technologies.