Effect of Sand-Frying-Triggered Puffing on the Multi-Scale Structure and Physicochemical Properties of Cassava Starch in Dry Gel.

Yonglin He,Sheng Li,Damao Wang,Guohua Zhao,Jia Chen,Fayin Ye

doi:10.3390/biom11121872

Yonglin He, Sheng Li + Show 4 more

Open Access

https://doi.org/10.3390/biom11121872

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Abstract

This study revealed the underlying mechanisms involved in the puffing process of dried cassava starch gel by exploring the development of the puffed structure of gel upon sand-frying, chiefly focused on the changes in the multi-scale structure and the physicochemical properties of starch. The results suggested that the sand-frying-induced puffing proceeded very fast, completed in about twenty seconds, which could be described as a two-phase pattern including the warming up (0~6 s) and puffing (7~18 s) stages. In the first stage, no significant changes occurred to the structure or appearance of the starch gel. In the second stage, the cells in the gel network structure were expanded until burst, which brought about a decrease in moisture content, bulk density, and hardness, as well as the increase in porosity and crispness when the surface temperature of gel reached glass transition temperature of 125.28 °C. Upon sand-frying puffing, the crystalline melting and molecular degradation of starch happened simultaneously, of which the latter mainly occurred in the first stage. Along with the increase of puffing time, the thermal stability, peak viscosity, and final viscosity of starch gradually decreased, while the water solubility index increased. Knowing the underlying mechanisms of this process might help manufacturers produce a better quality of starch-based puffed products.

Highlights

Accepted: 12 December 2021As is well known, starch is a versatile ingredient widely used in various foods as a thickener, stabilizer, or a gelling agent
The alterations of appearance, puffing ratio, porosity and moisture content, color, and textural properties of starch gel in the sand-frying puffing process were investigated, and associated results were displayed in Figure S1 and Table 1
Starch was only degraded during the stage. These results revealed that hierarchical degradation of cassava starch occurred puffing stage [26]

Summary

Introduction

Accepted: 12 December 2021As is well known, starch is a versatile ingredient widely used in various foods as a thickener, stabilizer, or a gelling agent. To ensure the high quality of starch-based snacks, puffing methods such as extrusion puffing, hot air puffing, microwave puffing, oil frying puffing, gun puffing, and sand- or salt-frying puffing, were adopted as a critical procedure in their production [6]. By these means, a serial of high quality puffed products was produced from cereal grains (wheat, oat, rye, barley, rice, black rice, glutinous rice, maize, sorghum, millet, and buckwheat) [7,8,9], amaranth seeds [10], quinoa seeds [11], chickpea [12], banana slices [13], mango chips [14], and fish crackers [15]

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