Structural Factors Responsible for Dynamic Rheological Properties during Gelatinization and Retrogradation of Starches

影響澱粉糊化與回凝動態流變性質之結構因素

賴鳴鳳(Vivian M. F. Lai) ； 蔡玫琳(Mei-Lei Tsai) ； 呂政義(Cheng-Yi Lii)

《中央研究院化學研究所集刊》 44期 (1997/03) Pp. 71-88

https://doi.org/10.6522/BICAS.1997.44.8

摘要

本文乃以秈（KSS7）、梗（TNu67）和糯米（TCW70）等三種米澱粉的顆粒與分子結構為基礎，系統地回顧其糊化與回凝時動態流變性質之發展。文中分別討論了澱粉的膨潤－溶解性與顆粒硬度對其動態流變參數的貢獻，並藉以解析其對糊化與回凝機制之影響。整體而言，澱粉糊化時動態儲存模數（G'）的增加主要受到緊密堆積的顆粒特性所影響，而回凝時之G'值的增加則隨溶出的或添加的直鏈澱粉分子及膨潤顆粒間的交互作用所左右。混合糯性和非糯性米澱粉會導致澱粉系統的G'值顯著降低；而添加2%直鏈澱粉分子雖會降低米澱粉糊化之G'值，然會提高其回凝時之G'值，顯示了直鏈澱粉分子在回凝機制上有較重要的貢獻。上述這些行為都與澱粉分子的微細結構極為相關。

並列摘要

The dynamic rheological properties during gelatinization and retrogradation of rice starches are reviewed based on the granular and molecular structures of three rice starches isolated from indica (KSS7), japonica (TNu67), and waxy rice (TCW70), The contributions of the swelling-solubility properties and the granular rigidity of starches to their dynamic rheological properties have been discussed for the elucidation of starch gelatinization and retrogradation mechanisms. Generally, the storage modulus (G') increase during the gelatinization of starches is mainly governed by the characteristics of close-packed granules. However, the G' increase during subsequent retrogradation is influenced by the interactions between leached-out or added amyloses and swollen granules. A combination of waxy and non-waxy rice starches results in a drastically decreased G', possibly due to phase separation, Addition of amylose molecules will also decrease G' values during gelatinization of starches, but increase them during retrogradation. All these behaviors are essentially correlated with the molecular structures of starch components.