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

•Provided basic information on the physicochemical properties of ginkgo starch.•Revealed the mechanism of higher resistance to α-amylase of ginkgo starch.•Compared the characteristics of ginkgo starch with normal maize and potato 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 (5–20 μm) with a smooth surface. Compared with normal maize and potato starches, ginkgo starch had a significantly higher amylose content of 33.26%, a CA-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 (1463 cP), gelatinization temperature (69.23 °C), lower swelling factor and gelatinization enthalpy (4.34 J/g). Moreover, ginkgo starch showed the lowest hydrolysis degree of the three starches in vitro, 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.

Graphical abstract13C CP/MAS NMR spectra of normal maize, potato, ginkgo and amorphous starches.Figure optionsDownload full-size imageDownload as PowerPoint slide