Zhang Tianmeng, Wang Ying, Zhu Jing, Chen Chao, Jiang Tao, Fang Siyi, Liu Hanghang, Tong Haoyun, Xia Qiang, Sun Yangying, Pan Daodong, Cao Jinxuan, Zhou Changyu
Zhejiang Key Laboratory of Intelligent Food Logistic and Processing; Zhejiang-Malaysia Joint Research Laboratory for Agricultural Product Processing and Nutrition; College of Food Science and Engineering, Ningbo University, Ningbo 315211, China.
China Food Flavour and Nutrition Health Innovation Center, Beijing Technology and Business University, Beijing 100048, China.
Food Chem. 2025 Apr 30;472:142991. doi: 10.1016/j.foodchem.2025.142991. Epub 2025 Jan 20.
To investigate the mechanism of Rhodotorula mucilaginosa on structural protein degradation and taste development of Jinhua ham, the effects of Rhodotorula mucilaginosa and Pichia kudriavzevii on proteolytic enzyme activities, surface hydrophobicity, myofibril microstructure, protein degradation, free amino acids and sensory attributes were investigated during the dry-ripening of Jinhua ham. The inoculation of Rhodotorula mucilaginosa EIODSF019 (RE) and Rhodotorula mucilaginosa XZY63-3 (RX) consistently exhibited higher proteolytic enzyme activities compared with Pichia kudriavzevii XS-5 (PK). The decrease of α-helix exposing more internal hydrophobic groups of myofibrillar proteins, contributed to higher surface hydrophobicity of RE compared with PK and RX. RE showed the highest proteolysis index among all groups, which could be attributed to more degradation of myosin, actin and troponin; the changes were confirmed by the intense breakdown of myofibrils observed by atomic force microscopy and transmission electron microscopy. 36 down-regulated proteins mainly derived from myofibrils and catalysis-related enzymes were identified in RE by TMT-labeled quantitative proteomics analysis. The degradation of myosin, actin and troponin showed the most intense response to the accumulation of glutamic acid, lysine and alanine. Partial least square regression analysis and correlation analysis revealed that the breakdown of MYH14, MYH3, TNNI1 and TNNTI was highly correlated with improvement of umami, richness and aftertaste.
为探究黏液红酵母对金华火腿结构蛋白降解及风味形成的作用机制，研究了黏液红酵母和季也蒙毕赤酵母在金华火腿干腌过程中对蛋白水解酶活性、表面疏水性、肌原纤维微观结构、蛋白质降解、游离氨基酸及感官特性的影响。与季也蒙毕赤酵母XS-5（PK）相比，接种黏液红酵母EIODSF019（RE）和黏液红酵母XZY63-3（RX）后蛋白水解酶活性始终较高。α-螺旋减少，肌原纤维蛋白内部疏水基团暴露增加，使得RE的表面疏水性高于PK和RX。RE在所有组中表现出最高的蛋白水解指数，这可能归因于肌球蛋白、肌动蛋白和肌钙蛋白的更多降解；原子力显微镜和透射电子显微镜观察到肌原纤维的强烈分解证实了这些变化。通过TMT标记定量蛋白质组学分析，在RE中鉴定出36种下调蛋白，主要来源于肌原纤维和催化相关酶。肌球蛋白、肌动蛋白和肌钙蛋白的降解对谷氨酸、赖氨酸和丙氨酸的积累反应最为强烈。偏最小二乘回归分析和相关性分析表明，MYH14、MYH3、TNNI1和TNNTI的分解与鲜味、丰富度和余味的改善高度相关。
