茶多酚对馒头品质的影响及机理初探

Effects of Tea Polyphenols on the Quality of the Steamed Bun and Its Mechanism

探究茶多酚对馒头品质的影响并初步分析其分子作用机理。系统观察了茶多酚对馒头比容、质构、硬化速度及α-淀粉含量的影响;测定了茶多酚对淀粉的碘结合能力、溶解度、膨胀势以及热特性的影响;采用分子动力学模拟,探究了茶多酚与淀粉分子的相互作用。结果表明,茶多酚能够显著影响馒头的比容和质构,将硬化速度由195 g/h降低至138 g/h,并提高其α-淀粉含量;茶多酚的添加可降低淀粉的碘结合能力,提高溶解度(8.3%~38.1%)和膨胀势(11.4%~13.8%),降低糊化峰值温度(62.21~53.57℃)以促进淀粉的糊化,并延缓淀粉的老化;茶多酚主要通过氢键(最高占比氢键4GA_12@O2:EGCG_1@H18;占比5.6%)与淀粉发生分子相互作用,进而改变淀粉分子的空间构型,影响其理化特性。研究结果表明,茶多酚可以改变淀粉的理化特性和品质特性,具有作为新型淀粉改良剂的潜在价值。

Effects of tea polyphenols(TP)on the quality of the steamed bun was studied,and its molecular action mechanism was preliminary analyzed.The effects of TP on the specific volume,texture,hardening rate andα-starch content of steamed bun were systematically observed.And the effects of TP on the iodine binding capacity,solubility,swelling power and thermal properties of starch were determined.And then the molecular dynamics(MD)was used to study the interaction between TP and starch molecules.The results showed that TP had a significant effect on the specific volume and texture.Besides,TP could decrease the hardening rate(from 195 to 138 g/h)and increased theα-starch content of the steamed bun;the addition of TP decreased the iodine binding capacity,increased the solubility(from 8.3%to 38.1%)and swelling power(from 11.4%to 13.8%),and decreased the gelatinization peak temperature(from 62.21 to 53.57℃)for promoting the gelatinization of starch and delaying the retrogradation of starch.Furthermore,TP could interact with starch by hydrogen bonds(highest occupancy hydrogen bonds 4GA_12@O2:EGCG_1@H18,ratio was 5.6%),and changed the spatial configuration of starch molecules,leading to the variation of the physicochemical properties of starch.The results indicated that TP could change the physicochemical and quality characteristics of starch,and had potential value as a new starch modifier.