茶多酚在钙交联果胶/壳聚糖复合膜中的缓释性研究

分别制备了果胶/壳聚糖复合膜和钙交联的果胶/壳聚糖复合膜，研究不同配比对膜溶胀性的影响以及茶多酚在钙交联复合膜中的释放行为。结果表明，果胶/壳聚糖膜随着配比的不同，溶胀率随之变化，溶胀率最小的膜是果胶与壳聚糖之比为1:0.5，2 h的溶胀率为9.5。钙交联果胶/壳聚糖膜的溶胀率与钙含量有关，适量的钙交联使膜的溶胀率降低，其最小溶胀率在6 h只有2.1，过量的钙会导致膜的溶胀率增大。茶多酚在交联膜中的缓释规律与溶胀率一致，释放率随着钙交联度的增加而减少，但过量的钙使得释放率变大，可通过调节钙用量来控制茶多酚的释放率；茶多酚释放率随着茶多酚含量的增加而增大，在pH=3的溶液中释放速率大于pH=9的溶液。

Controlled Release of Tea Polyphenols from Calcium-crosslinked Pectin/Chitosan Complex Films

Pectin/chitosan films and calcium-crosslinked pectin/chitosan complex films were prepared. The effect of different proportions on swelling ratio of films and the release rate of tea polyphenols from crosslinked films were investigated. The results indicated that the lowest swelling ratio of pectin/chitosan films was 9.5 after 2 h when the pectin-chitosan ratio was 1:0.5. The swelling ratio of calcium-crosslinked pectin/chitosan films varied with calcium content and the lowest one was only 2.1 after 6 h. The excess calcium caused increase of the swelling ratio. The controlled release rule of tea polyphenols from crosslinked films agreed with swelling ratio of the films and the release rate can be controlled by calcium content. The release rate decreased with increasing calcium crosslink level, but increased with excess calcium content. The release rate increased with increasing tea polyphenols contents. Tea polyphenols released faster in solution at pH 3 than that at pH 9.