Multifunctionalities of oleyl-branched oligosaccharide phosphate from potato starch with a high phosphate content.

Branched oligosaccharide phosphate (BOS-P) and oleyl BOS-P (OA-BOS-P) were prepared from potato starch with a high phosphate content by limited amylolysis with α-amylase and exhaustive digestion with glucoamylase and oleylation of BOS-P through a lipase-catalyzed solid-phase synthesis. The multifunctional properties of OA-BOS-P were evaluated in terms of surface tension, emulsifying ability, Ca(2+)-binding ability, and ability to control the gelatinization and retrogradation of potato starch. OA-BOS-P exhibited better emulsifying ability than BOS-P and Ca(2+)-binding ability similar to that of BOS-P. OA-BOS-P elevated the gelatinization temperature and reduced viscosity more than BOS-P. OA-BOS-P also reduced retrogradation as indicated by the reduction in the setback viscosity, turbidity, development of the ordered structure and crystalline structure, and digestibility, whereas BOS-P elevated the setback and turbidness, despite reducing the development of the crystalline structure, except for development of the ordered structure, similar to that of the control. These results show that OA-BOS-P could be a useful material with novel emulsifying, Ca(2+)-binding, and starchy food-controlling properties.