Antiretrogradation in cooked starch-based product application of tea polyphenols.

Abstract

Retrogradation in cooked starch-based products is a significant hindrance in extending the shelf life of these products as they become progressively hard to bite over short time periods (say 1 or 2 months). In this study, the effects of tea polyphenols (TPs) on cooked amylopectin-rich cassava starch have been investigated. Cassava starch was mixed with TPs and then gelatinized to form starch gels. The obtained gels were stored for up to 80 d and characterized by X-ray diffraction (XRD), hardness test, color analysis, and Fourier transform infrared spectroscopy (FT-IR). The results of XRD show that the formation of long-range ordered structure of amylopectin was retarded by the interaction of TPs with amylopectin via hydrogen bond. The results of hardness test show that the accelerating increase in the hardness of cassava starch gel was retarded by the addition of TPs. The increase in hardness versus time can be correlated well using a single-parameter exponential equation. The increase in hardness, variations in color, and FT-IR spectrum of the TPs treated samples during storage with TPs were relatively small, suggesting that the retrogradation of starch is inhibited by TPs. This work presents an opportunity of antiretrogradation in the related products. Retrogradation of cooked-starch-based products is still one of the most frequently encountered problems in food industry, which causes many problems such as hardening and syneresis of the products. The potential application of tea polyphenols (TPs) as antiretrogradation additives is demonstrated in this work. Experimental results show that the addition of TPs retards the retrogradation of cassava starch during long-term storage remarkably.