pH值对壳寡糖-柠檬酸盐-果胶自组装的影响

Effect of pH on the Self-Assembly of Chitooligosaccharide-Citrate-Pectin

通过研究不同pH值条件下壳寡糖-柠檬酸盐-果胶复合溶液的浊度、宏观/微观状态,结合复合物红外光谱及扫描电镜超微结构分析,探讨了pH值对壳寡糖-柠檬酸盐-果胶自组装行为的影响。结果表明:pH值会影响壳寡糖、柠檬酸盐与果胶分子之间的静电与氢键作用,且随着pH值的提高,复合溶液浊度呈先上升后下降的趋势,当pH值为5时浊度高达89.72%,链状复合物相互交错叠加、出现沉淀物;当pH3或pH6时,复合溶液可保持均匀、稳定状态。该结果可为壳寡糖在果汁及其他含聚阴离子食品体系的运用提供参考。

By studying the turbidity,macroscopic/microscopic state of chitooligosaccharide-citrate-pectin composite solution under different pH conditions,combined with the composite infrared spectroscopy and scanning electron microscope ultrastructural analysis,the effect of pH on chitooligosaccharid-citrate-pectin self-assembly was discussed.The results show that pH will affect the electrostatic and hydrogen bonding between chitooligosaccharide,citrate and pectin,and with the increase of pH,the turbidity of the composite solution first increases and then decreases.When pH is 5,the turbidity is as high as 89.72%,and the chain-like complexes are interlaced and superimposed,and precipitates appear;when pH3 or pH6,the complex solution can maintain a uniform and stable state.The results can provide reference for the application of chitooligosaccharide in fruit juice and other food systems containing polyanions.