The molecular mechanism by which emulsifiers inhibit starch retrogradation has not been fully understood. The retardation effect of emulsifiers on potato starch retrogradation was investigated using dynamic viscoelastic measurements and differential scanning calorimetry. Molecular-level investigations of the adsorption between starch and amylose with sucrose fatty acid esters were conducted using isothermal titration calorimetry to elucidate the mechanism by which emulsifiers attenuate starch retrogradation. Starch gels containing highly hydrophilic and poorly hydrophilic emulsifiers exhibited a small increase in storage elastic modulus at 4 degrees C. Amylose chains exist in water with their helices loosened, and the hydrophilic groups of sucrose fatty acid ester molecules adsorb onto the amylose chains via hydrogen bonding and van der Waals interactions. The adsorbed emulsifiers acted as steric hindrance and inhibited amylose chain reaggregation, thus suppressing retrogradation. Through a multi-scale investigation-using rheology, thermal analysis, and calorimetry-this study effectively elucidates the molecular-level inhibitory effects of emulsifiers on starch retrogradation.
