Study on physicochemical and in-vitro enzymatic hydrolysis properties of ginkgo (Ginkgo biloba) starch

Ginkgo biloba seed starch was isolated and its morphological, compositional, physicochemical, and structural characteristics, and in-vitro enzymatic hydrolysis, were investigated. Ginkgo starch granules were oval or spherical (5-20μm) with a smooth surface. Compared with normal maize and potato starches, ginkgo starch had a significantly higher amylose content of 33.26%, a C_A-type crystal pattern and a significantly higher crystallinity degree (40.2%). Because of its different chemical composition and structural characteristics, ginkgo starch exhibited a higher pasting temperature (80.95°C), setback viscosity (1463cP), gelatinization temperature (69.23°C), lower swelling factor and gelatinization enthalpy (4.34J/g). Moreover, ginkgo starch showed the lowest hydrolysis degree of the three starches invitro, indicating its higher resistance to α-amylase digestibility in the case of retrogradation. The present study demonstrated that ginkgo starch is a robust and potentially useful nutritional source of enzyme-resistant starch, and provides useful information for food industries using ginkgo seeds.