Effect of soybean polysaccharide and soybean oil on gelatinization and retrogradation properties of corn starch

Abstract

This investigation stems from the wide interest in mitigating starch retrogradation, which profoundly impacts the quality of starch-based food, garnering significant attention in the contemporary food industry. Our study delves into the intricate dynamics of soluble soybean polysaccharide (SSPS) and soybean oil (SO) when added individually or in combination to native corn starch (NCS), offering insights into the gelatinization and retrogradation phenomena. We observed that SSPS (0.5 %, w/w) hindered starch swelling, leading to an elevated gelatinization enthalpy change (∆H) value, while SO (0.5 %, w/w) increased ∆H due to its hydrophobicity. Adding SSPS and/or SO concurrently reduced the viscosity and storage modulus (G') of starch matrix. For the starch gel (8 %, w/v) after refrigeration, SSPS magnified water-holding capacity (WHC) and decreased hardness through hydrogen bonding with starch, while SO increased hardness with limited water retention. Crucially, the combination of SSPS and SO maximized WHC, minimized hardness, and significantly inhibited starch retrogradation. The specific ratio of SSPS to SO was found to significantly influence the starch properties, with a 1:1 ratio resulting in the most desirable quality for application in starch-based foods. This study offers insights for utilizing polysaccharides and lipids in starch-based food products to extend shelf life.

Keywords: Corn starch; Soluble soybean polysaccharide; Soybean oil; Starch gelatinization; Starch retrogradation; Starch rheological properties.