卡拉胶对酸乳稳定性的影响与机制  

Effect of Carrageenan on the Stability of Yogurt and Its Mechanism

作　　者：王辉[1] 张洪凯[1] 余子阳 李胜 胡秀婷[1] WANG Hui;ZHANG Hongkai;YU Ziyang;LI Sheng;HU Xiuting(State Key Laboratory of Food Science and Resources,Nanchang University,Nanchang 330047,China)

机构地区：[1]南昌大学食品科学与资源挖掘全国重点实验室,江西南昌330047

出　　处：《食品科学》2025年第8期1-7,共7页Food Science

基　　金：国家自然科学基金地区科学基金项目(32160541)。

摘　　要：为阐明多糖亲水胶体对酸乳稳定性的影响机制,以卡拉胶为多糖亲水胶体代表,研究不同添加量卡拉胶对酸乳稳定性的影响以及卡拉胶与酪蛋白胶束的相互作用。结果发现,低添加量卡拉胶(0.05%)显著提高酸乳的稳定性,高添加量卡拉胶(≥0.10%)则降低酸乳的稳定性。相应地,当卡拉胶添加量低时,酸乳中蛋白质分布更均匀;而卡拉胶添加量高时,酸乳中形成了更大的乳清囊。流变学分析表明,添加卡拉胶提高了酸乳的黏度、储能模量(G’)和损耗模量(G”),且卡拉胶添加量越高,酸乳的黏度、G’和G”越大。这证明卡拉胶在酸乳中具有增稠作用,卡拉胶添加量越大,增稠作用越强。进一步研究卡拉胶与酪蛋白胶束的相互作用发现,当卡拉胶添加量为0.05%时,卡拉胶与酪蛋白胶束互溶;当卡拉胶添加量超过0.10%时,酪蛋白胶束聚集、尺寸增大甚至沉淀析出。此外,将卡拉胶溶液与酪蛋白胶束悬浮液混合时,体系的熵变(ΔS)为负值。这些结果表明卡拉胶与酪蛋白胶束在热力学上不相容,二者相互作用可能引起相分离。由此推测,当卡拉胶添加量较低时,卡拉胶与酪蛋白胶束互溶,此时,卡拉胶在酸乳中的增稠作用占主导作用,因此,低添加量卡拉胶提高酸乳的稳定性;当卡拉胶添加量较高时,卡拉胶与酪蛋白胶束热力学不相容引起相分离,降低了酸乳的稳定性。To elucidate the mechanism by which polysaccharide hydrocolloids affect yogurt stability,the effect of adding different concentrations of carrageenan as a representative of polysaccharide hydrocolloids in yogurt on its stability was investigated along with the interaction between carrageenan and casein micelles.It was found that carrageenan at a low concentration(0.05%)significantly improved yogurt stability,but exerted the opposite effect at a high concentration(≥0.10%).Correspondingly,the addition of low concentrations of carrageenan resulted in more uniform protein distribution in yogurt,while high concentrations of carrageenan led to the formation of larger whey pockets.Interestingly,rheological analysis showed that adding carrageenan increased yogurt viscosity,storage modulus(G’),and loss modulus(G”),and this effect was more pronounced at higher carrageenan concentration.This finding demonstrated that carrageenan had a thickening effect on yogurt,which increased with the increase in its concentration.Analysis of the interaction between carrageenan and casein micelles found that carrageenan at 0.05%concentration and casein micelles were miscible with each other.When the carrageenan concentration exceeded 0.10%,casein micelles were aggregated and even precipitated.Additionally,the entropy change(ΔS)of mixing carrageenan solution and casein micelle suspension was negative.These results indicated that carrageenan and casein micelles were thermodynamically incompatible,and their interaction might lead to phase separation.Thus,it was speculated that at low concentrations,carrageenan was miscible with casein micelles,and played a dominant role in thickening yogurt,thereby improving its stability.However,incompatibility between carrageenan at high concentrations and casein micelles led to phase separation,thus reducing yogurt stability.

关 键 词：酸乳 稳定性 卡拉胶 酪蛋白胶束 增稠作用 热力学相互作用 

分 类 号：TS201.7[轻工技术与工程—食品科学]