Study on the Preparation of V-type Porous Starch with High Oil Absorption Capacity

Abstract

In this research, V-type porous starch (VPS) with high oil absorption capacity was obtained by enzymatic hydrolysis of V-type granular starch (VGS) in ethanol aqueous solution. Firstly, the reaction condition of V-type granular starch (VGS) was optimized with oil absorption capacity and V-type crystal crystallinity as indexes. In 50% ethanol, aqueous solution the oil absorption capacity of VGS obtained by reaction 100 ℃ was the highest (176.23%). Then, the influence of enzymatic hydrolysis time, temperature and speed on the degree of hydrolysis, yield and oil absorption capacity of VPS were investigated. The optimal preparation conditions of VPS were obtained through single factor and orthogonal experiments: enzymatic hydrolysis time 4 h, temperature 25 ℃, and enzymatic hydrolysis speed 300 r/min. The oil absorption capacity of the optimal VPS was the highest (550.28%). Finally, the difference in the crystalline structure, granular morphology, specific surface area and bulk density were compared among normal maize starch (NMS), traditional A-type porous starch, VGS and VPS. VPS exhibited a unique sponge shaped irregular dense honeycomb structure, the highest specific surface area (39.94 m2/g) and the lowest bulk density (0.19 g/cm3), which were the reasons for its higher oil absorption capacity.

Keywords

• v-type granular starch
• aqueous-ethanol heat treatment
• ethanol-phase enzymatic hydrolysis
• v-type porous starch
• oil absorption capacity