Effect of hydrophilic groups in lipids on the characteristics of starch–lipid complexes

Abstract

SummaryThe complexation of starch and lipids has important implications for food quality, and the interaction is affected by hydrophilic groups in lipids. The complexation interaction of palmitic acid and its common esters with starch was investigated to clarify the influence of the hydrophilicity of polar heads in lipids. The results indicate that the difference in hydrophilic groups affected the characteristics of starch–lipid complexes. The difficulty level of complexation with starch was in the order of palmitic acid > glyceryl monopalmitate > L‐ascorbyl palmitate, with the degree of double helix of the L‐ascorbyl palmitate complex being the lowest. In contrast with palmitic acid, the viscoelasticity of complexes formed by glyceryl monopalmitate and L‐ascorbyl palmitate with a higher number of hydroxyl groups was enhanced and exhibited obvious elastic characteristics. The more intensive complexation interaction caused the more evident changes of the 13C NMR chemical shift attributed to starch. For the complexes of L‐ascorbyl palmitate, glyceryl monopalmitate, and palmitic acid, chemical shift values of carbon at the methylene in glucose units shifted upfield by 0.34, 0.18, and 0.10 ppm, respectively. Hence, hydrophilic groups in lipids significantly affected the formation, structure, and physicochemical properties of starch–lipid complexes.