摘要
采用含不同浓度H_(2)O_(2)(0.0~10.0 mmol/L)的Fenton体系(H_(2)O_(2)-VC-FeCl_(3))模拟氧化应激环境对鲢鱼肌原纤维蛋白进行氧化,测定蛋白的巯基含量,以及蛋白凝胶的凝胶强度、白度、持水性、水分分布状态及微观结构,探究氧化度对蛋白凝胶特性的影响。结果表明:随着H_(2)O_(2)浓度的增加,蛋白的总巯基含量和白度、持水性呈先升高后降低的趋势。当体系中H_(2)O_(2)浓度较低(0.1~0.5 mmol/L)时,蛋白凝胶强度增大,白度得到改善;凝胶的三维结构孔洞的面积较小,且分布较为均匀,凝胶的持水力有所增强。但是当体系中的H_(2)O_(2)浓度较高(5.0~10.0 mmol/L)时,蛋白凝胶的白度下降,凝胶结构的有序性降低,孔洞面积变大,分布变得不均匀,凝胶的持水力下降,凝胶品质发生劣变。因此,适度氧化(0.1~0.5 mmol/L H_(2)O_(2))有助于蛋白凝胶特性的提高。肽段的LC-MS/MS结果显示,羟自由基对蛋白的主要氧化区域为肌球蛋白重链和肌动蛋白,甲硫氨酸、半胱氨酸、天冬氨酸和谷氨酸为高频氧化位点。
In this study,silver carp myofibrillar protein(MP)was oxidized with different concentrations of H_(2)O_(2)(0.0‒10.0 mmol/L)in the Fenton system(H_(2)O_(2)-VC-FeCl_(3))to explore the effect of oxidation degree on protein gel formation and gel properties.The sulfhydryl content of MP was measured.The gel strength,whiteness,water-holding capacity,moisture distribution and microstructure of MP gels were determined.The results showed that as H_(2)O_(2) concentration increased,the total sulfhydryl content,whiteness and water-holding capacity of MP increased first and then decreased.When the H_(2)O_(2) concentration in the system was low(0.1‒0.5 mmol/L),the gel strength and whiteness were both improved.The area of pores in the three dimensional gel structure became smaller,the distribution became more uniform,and the water-holding capacity of MP gels was enhanced.However,at high H_(2)O_(2) concentration(5.0‒10.0 mmol/L),the gel whiteness decreased,and the gel structure became disordered,the pore area became larger,the pore distribution became nonuniform,and the water-holding capacity decreased,indicating a deterioration in gel quality.Therefore,appropriate oxidation(0.1‒0.5 mmol/L H_(2)O_(2))contributed to the improved properties of protein gels.The analysis of the peptide composition by liquid chromatography-tandem mass spectrometry(LC-MS/MS)showed that the major oxidation regions of MP by hydroxyl radicals were the heavy chain of myosin and actin.Moreover,methionine,cysteine,aspartic acid and glutamic acid were recognized as the high-frequency oxidation sites of MP.
作者
张海萍
余小月
程梦颖
熊善柏
刘友明
ZHANG Haiping;YU Xiaoyue;CHENG Mengying;XIONG Shanbai;LIU Youming(National R&D Branch Center for Conventional Freshwater Fish Processing(Wuhan),College of Food Science and Technology,Huazhong Agricultural University,Wuhan 430070,China)
出处
《食品科学》
EI
CAS
CSCD
北大核心
2023年第6期9-16,共8页
Food Science
基金
国家自然科学基金面上项目(31871835)
财政部和农业农村部国家现代农业产业技术体系项目(CARS-45-28)。
