Structural and physicochemical/digestion characteristics of potato starch-amino acid complexes prepared under...

Amino acids (AAs) are increasingly applied as nutrient supplements and played a crucial role in human nutrition and health maintenance. The objectives were to evaluate the effects of different AAs on the physicochemical and digestive properties of potato starch (PS); and investigate whether heat moisture treatment (HMT) or annealing (ANN) had different impacts on the complexes between starch and AAs. PS mixed with different AAs, represented by Lys, Ser, Ala, and Asp, were modified by HMT and ANN. Both different AAs addition and hydrothermal treatments significantly increased the pasting and gelatinization temperatures, and decreased swelling power, peak viscosity and enthalpy change for physically mixed samples. In general, different AAs retarded the recrystallization of PS, while hydrothermal treatments promoted retrogradation of PS. The addition of different AAs decreased the RDS and increased RS contents for all cooked samples. Electrostatic interactions between PS with phosphate-monoester derivatives and different charge-carrying AAs formed during hydrothermal treatments, resulting in modify physicochemical and digestive properties of PS. HMT showed greater influence on physicochemical and digestive properties of PS-AA complexes than ANN. This study will enrich interaction theory between starch and AAs, and improve the nutritional values of PS-based products during food thermal processing.