超声波辅助pH偏移处理对猪肝蛋白结构及乳化特性的影响  

Effect of Ultrasound-Assisted pH-shifting Treatment on the Structure and Emulsification Characteristics of Porcine Liver Protein

作　　者：陆今明 彭松林 杨凯麟 耿宏庆 尚永彪[1,2] LU Jin-ming;PENG Song-lin;YANG Kai-lin;GENG Hong-qing;SHANG Yong-biao(College of Food Science,Southwest University,Chongqing 400715,China;Chongqing Key Laboratory of Speciality Food Co-Built by Sichuan and Chongqing,Chongqing 400715,China)

机构地区：[1]西南大学食品科学学院,重庆400715 [2]川渝共建特色食品重庆市重点实验室,重庆400715

出　　处：《食品研究与开发》2023年第5期89-96,共8页Food Research and Development

摘　　要：该文探讨不同方法改性处理对猪肝蛋白(porcine liver protein,PLP)结构功能特性的影响。通过超声波处理、pH偏移处理和超声波辅助p H偏移处理对PLP进行改性,测定改性PLP的溶解度、表面疏水性、乳化特性、巯基含量、粒径、Zeta电位、一级和三级结构等指标及其变化情况。结果表明,超声处理会使PLP粒径减小,溶解度与Zeta电位绝对值增大;将PLP溶液调至p H3随后调回至中性(pH3-7),会使PLP粒径增大,溶解度与Zeta电位绝对值下降,超声辅助pH偏移处理后(p H3U-7)会使蛋白粒径下降,溶解度与Zeta电位绝对值增加但效果并不明显;将PLP溶液调至pH9随后调回至中性(p H9-7)及加入超声处理(pH9U-7)会使蛋白粒径减小,溶解度及Zeta电位绝对值增大。酸碱pH偏移及超声复合处理均降低PLP的荧光强度、活性巯基含量。电泳结果显示,pH3-7可能导致PLP的二硫键聚集,pH9-7对电泳条没有明显影响,超声的加入不会进一步改变电泳条带。相较于对照组,超声处理、pH9-7组和pH9U-7组均提高PLP乳化活性和乳液稳定性,而pH3-7及pH3U-7组的乳化活性与乳液稳定性降低。The paper aimed to explore the effects of different modified methods on the structure and function characteristics of porcine liver protein(PLP). PLP was modified by ultrasonic treatment,pH-shifting treatment,and ultrasound-assisted pH-shifting treatment. The solubility,surface hydrophobicity,emulsification property,sulfhydryl content,particle size,Zeta potential,primary and tertiary structure,and their changes in the modified PLP were measured. The results showed that the particle size of PLP decreased and the absolute value of solubility and potential increased after ultrasonic treatment. When the PLP solution was adjusted to pH3 and then returned to neutral(pH3-7),the particle size of PLP increased,and the solubility and absolute potential decreased. After ultrasound-assisted pH-shifting treatment(pH3U-7),the particle size of protein decreased,and the solubility and absolute potential increased,but the effect was not obvious. When the PLP solution was adjusted to pH9,then returned to neutral(pH9-7),and combined with ultrasonic treatment(pH9U-7),the particle size of protein decreased,and the solubility and absolute potential increased. Acid/base pH-shifting and ultrasound-assisted treatment reduced the fluorescence intensity and active sulfhydryl content of PLP. The electrophoresis results showed that pH3-7 may lead to the disulfide bond aggregation of PLP,pH9-7 had no obvious effect on the electrophoresis strip,and the addition of ultrasound did not further change the electrophoresis strip. Compared with the control group,ultrasonic treatment,the pH9-7 and pH9U-7 groups improved the emulsifying activity and lotion stability of PLP,while the pH3-7 and pH3U-7 groups reduced the emulsifying activity and lotion stability.

关 键 词：超声波 pH偏移 猪肝蛋白 分子结构 乳化特性 

分 类 号：TS251.9[轻工技术与工程—农产品加工及贮藏工程]