Starch Retrogradation in Rice Cake: Influences of Sucrose Stearate and Glycerol.

Seon-Min Oh,Moo-Yeol Baik,Hee-Don Choi,Hyun-Wook Choi

doi:10.3390/foods9121737

Seon-Min Oh, Moo-Yeol Baik + Show 2 more

Open Access

https://doi.org/10.3390/foods9121737

Copy DOI

Abstract

Retrogradation properties and kinetics of rice cakes with the addition of glycerol (GLY) and sucrose fatty acid ester (SE) were investigated. In hardness, both rice cakes with glycerol (RGLY) and rice cakes with sucrose fatty acid ester (RSE) showed lower initial hardening compared with the control for up to 5 days. X-ray diffraction (XRD) pattern of RSE showed a B+V-type pattern, and the relative crystallinity showed that GLY and SE lowered the initial and final crystallization of rice cake. Both GLY and SE affected the retrogradation enthalpy, glass transition temperature, and ice melting enthalpy in differential scanning calorimeter (DSC). However, 1H NMR relaxation time (T2) of rice cake decreased regardless of additives. From these results, the addition of glycerol and sucrose stearate inhibits the retrogradation process of rice cakes, which will solve industrial problems. Applying the Avrami equation for retrogradation kinetics of rice cake was suitable in XRD and DSC with high coefficient of determination (0.9 < R2). Meanwhile, the other retrogradation index improved the R2 when the exponential rise to maximum equation was used. This suggests that there is an alternative of Avrami equation to predict the retrogradation.

Highlights

Rice cake is a traditional food developed since ancient time and mainly consumed in Asian countries
Retrogradation properties of rice cake with glycerol or sucrose fatty acid ester were investigated at macroscopic (Hardness), microscopic (DSC and X-ray diffraction (XRD)), and molecular levels (1 H NMR)
When glycerol and sucrose fatty acid ester were added to rice cake, they interfered with the starch re-association and recrystallization

Summary

Introduction

Rice cake is a traditional food developed since ancient time and mainly consumed in Asian countries. It is made with rice flour and water, and sugar or salt is added according to preference. Fresh rice cake has a sticky and soft texture, it tends to harden leading to poor digestibility and quality during storage. This is because starch, which is the main component of rice cake, will reassociate and recrystallize over time [1,2]. Many studies have attempted to retard starch retrogradation of rice cakes using various additives [5]

Methods

Results

Conclusion