摘要
研究了壳聚糖与果胶形成聚电介质复合物的作用。红外光谱IR图谱显示,壳聚糖和果胶形成的物质出现-NH3+-OOC-次价键,表明发生了-NH2和-COOH的次价键反应,说明壳聚糖和果胶分子之间发生了聚电解质反应。胶体滴定、浊度滴定实验结果表明,壳聚糖和果胶在pH5·0～6·0范围内按一定比例、通过静电相互作用形成聚电解质复合物(PEC)。壳聚糖与果胶形成PEC的最佳复合比例以及PEC临界转变pH(pHω)与壳聚糖的分子量、脱乙酰度密切相关。当壳聚糖的分子量由5万增至50万时,壳聚糖和果胶的最佳复合比例γφ由8∶2逐渐降低为3∶7,pHω由5·0升为6·0;壳聚糖脱乙酰度由80%升至95%时,γφ由8∶2逐渐降低为4∶6,pHω由6·5降为5·0。
Complexation between chitosan and pectin was studied.FIR spectrum of the polyelectrolyte complexes （PECs） showed that-NH3^＋ - OOC-secondary valent bond was formed between chitosan and pectin.This indicated that polyelectrolyte complexation was carried out between chitosan and pectin.The results of colloid and turbid titration shewed that PECs was formed by electronstatic interaction and in some proportion between chitosan and pectin at pH5.0-6.0.The optimium complexing proportion （γφ）of chitosan and pectin,transiting critical pH （pHω）of PECs was related with the degree of deacetylation （D.D） and Mw of chitosan.With the increasing of Mw of chitosan from 50kDa to 500kDa,the γφ decreased from 8：2 to 3：7 and pHω increased from 5.0 to 6.0 .With increasing of the D.D of chitosan from 80% to 95% ,the γφ decreased from 8：2 to 4：6 and pHω decreased from 6.5 to 5.0.
出处
《食品工业科技》
CAS
CSCD
北大核心
2009年第8期85-87,共3页
Science and Technology of Food Industry
基金
广东省科技计划项目(2007A020100001-11)
关键词
壳聚糖
果胶
聚电解质复合物
chitosan
pectin
polyelectrolyte complexes
