Physicochemical properties and in vitro digestibility of lotus seed starch-lecithin complexes prepared by dynamic high pressure homogenization

Abstract

The objective of this study was to investigate the physicochemical properties and in vitro digestibility of lotus seed starch-lecithin inclusion complexes (ICs), prepared by dynamic high pressure homogenization. Raman spectrometry indicated that the IC formed between starch and lecithin, compared with the control mixture, could modify the helix rearrangement between different amylose conformations, to promote the formation of an ordered and stable V-type conformation. The content of amylose single helix appeared to be an important factor in the formation of starch-lipid complexes. Dispersion stability and solubility determinations indicated that the effect of mixing lecithin with starch mainly focused on the dispersion stability and not the solubility of starch emulsions. ICs with a V-type conformation, formed by homogenization of lecithin and amylose, achieved the same, or better emulsion stability as mixed lecithin, and the formation of ICs reduced the affinity of starch chains for water molecules, lowering their solubility. Digestion analysis suggested that the higher proportion of microcrystalline region in V6I complexes, resulted in a lower digestion rate and a higher resistant starch (RS) content.