氨基酸对大米淀粉糊化和流变性质的影响  

Effects of Amino Acids on Pasting and Rheological Properties of Rice Starch

作　　者：罗舜菁[1] 李燕[1] 杨榕[1] 胡秀婷[1] 刘云飞[1] 刘成梅[1] LUO Shunjing;LI Yan;YANG Rong;HU Xiuting;LIU Yunfei;LIU Chengmei(State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China)

机构地区：[1]南昌大学食品科学与技术国家重点实验室,江西南昌330047

出　　处：《食品科学》2017年第15期178-182,共5页Food Science

基　　金：食品科学与技术国家重点实验室目标导向项目(SKLF-ZZA-201608)

摘　　要：以赖氨酸(lysine,Lys)、天冬氨酸(aspartic acid,Asp)和丙氨酸(alanine,Ala)分别代表带正电、负电、不带电3类氨基酸,采用快速黏度分析仪和流变仪研究氨基酸对大米淀粉糊化和流变性质的影响。结果表明,Lys和Asp均显著提高了大米淀粉的峰值黏度和崩解值(P<0.05),但是降低了淀粉的最终黏度和回生值,而Ala对淀粉的糊化性质影响微小,在一定浓度范围内无显著差异(P>0.05)。因此,带电的2种氨基酸(Lys和Asp)比不带电氨基酸(Ala)对淀粉糊化性质影响更强。此外,3种氨基酸对大米淀粉糊流变性质影响不同:动态流变学实验中,添加Lys和Ala使淀粉凝胶更具弹性,而Asp使淀粉凝胶变弱;静态流变学实验中,运用幂定律τ=kγm,对剪切应力τ和剪切速率γ进行了拟合,结果表明,原淀粉与添加氨基酸的淀粉的m值均小于1,表明淀粉及其氨基酸混合物都属于假塑性流体,并且Lys使淀粉假塑性增强,而Asp则相反。The objective of this study was to evaluate the effects of positively charged,neutral charged and negatively charged amino acids,represented by Lys,Ala,and Asp,respectively,on pasting and rheological properties of rice starch.The results showed that both Lys and Asp significantly increased peak viscosity(PV)and breakdown(BD)of rice starch and reduced final viscosity(FV)and setback(ST)(P<0.05).However,Ala had little influence on pasting properties(P>0.05).Thus,the two charged amino acids(Lys and Asp)had stronger effects on rice starch than the neutral one(Ala).In addition,all three amino acids had different effects on rheological properties of rice starch.Lys and Ala resulted in increased elasticity of starch gel,while Asp had the opposite effect.Besides,the relationship between shear stressτand shear rateγduring the steady flow test was analyzed by using the power law modelτ=kγm,and the results showed that the m values of all samples were<1,suggesting that both starch and starch-amino acid mixture were pseudoplastic fluid.Additionally,Lys enhanced the pseudoplastic behavior,while Asp had the opposite effect.

关 键 词：大米淀粉 氨基酸 糊化性质 流变性质 

分 类 号：TS235.1[轻工技术与工程—粮食、油脂及植物蛋白工程]