Department of Food Science and Technology, Luiz de Queiroz College of Agriculture, University of Sao Paulo, Piracicaba, SP 13418-900, Brazil.
Lipid Marker Omics Sciences, Pirassununga, SP 13638-407, Brazil.
Meat Sci. 2025 Jan;219:109682. doi: 10.1016/j.meatsci.2024.109682. Epub 2024 Oct 5.
This study aimed to explore the differences in the lipidome and mitochondrial fraction metabolome of Nellore cattle meat in different ranges of ultimate pH (pHu) normal (≤5.79), intermediate (5.80 to 6.19) and high (≥ 6.20) after 3- and 21-d postmortem. Instrumental color, myoglobin redox state, oxygen consumption, and metmyoglobin-reducing activity were measured during storage. A total of 472 lipids and 22 mitochondrial fraction metabolites were identified. Beef with high pHu showed positive regulation of ceramides involved in apoptosis and negative regulation of lipid classes related to membrane permeability and stability. In addition, lower carnitine content was noted in high-pHu beef than in normal-pHu beef. Acylcarnitines, phosphatidylinositol, and IMP showed upregulation in beef with intermediate pHu, indicating changes mainly related to energy, purine and pyruvate metabolism. Aging time impacted on the lipid content and metabolites involved in different metabolic pathways. These results provided new insights into beef's mitochondrial fraction lipid and metabolic profile with different pHu. In addition, beef with intermediate pHu differs from beef with high pHu due to changes in energy metabolism.
本研究旨在探讨不同终极 pH 值（pHu）范围（正常范围：≤5.79、中间范围：5.80 至 6.19 和高范围：≥6.20）下，3 天和 21 天宰后内罗尔牛肉脂质组和线粒体部分代谢组的差异。在贮藏过程中测量仪器颜色、肌红蛋白氧化还原状态、耗氧量和高铁肌红蛋白还原活性。共鉴定出 472 种脂质和 22 种线粒体部分代谢物。高 pHu 的牛肉表现出与细胞凋亡有关的神经酰胺的正调控，以及与膜通透性和稳定性有关的脂质类别的负调控。此外，高 pHu 牛肉中的肉碱含量低于正常 pHu 牛肉。酰基辅酶 A、磷脂酰肌醇和 IMP 在 pHu 中间的牛肉中上调，表明主要与能量、嘌呤和丙酮酸代谢有关的变化。老化时间影响不同代谢途径中涉及的脂质含量和代谢物。这些结果为不同 pHu 下牛肉线粒体部分的脂质和代谢特征提供了新的见解。此外，由于能量代谢的变化，pHu 中间的牛肉与 pHu 高的牛肉不同。
