Physicochemical Properties of Α-Glucan Coating on Raw Starch Surface by Amylosucrase from Neisseria Polysaccharea

PS2 Poster session 2 Even numbers
Location (hall): 
Start/end time: 
Tuesday, July 2, 2019 - 15:45 to 17:15

Moon-Gi Hong1, Dong-Ho Seo2, Cheon Seok Park3, Sang-Ho Yoo4, Byung-Hoo Lee1

1Department of Food Science and Biotechnology, Gachon University, Seongnam, South Korea, 2Research Group of Healthcare, Korea Food Research Institute, Wanju, South Korea, 3Graduate School of Biotechnology and Institute of Life Science and Resources, Kyung Hee University, Yongin, South Korea, 4Department of Food Science and Biotechnology, and Carbohydrate Bioproduct Research Center, Sejong University, Seoul, South Korea

Amylosucrase (AS), a glycosyltransferring enzyme, produces linear α-1,4 glucans from sucrose as a donor molecule. In this study, the α-glucan-coated starch (α-GCS) was produced by AS (20 U/Lreactant) from Neisseria polysaccharea to improve the physicochemical properties of raw normal corn starch (NCS) under various reaction conditions (substrate concentration, pH, and temperature). The field-emission scanning electron microscopy and X-ray diffraction showed that the raw NCS was successfully coated by α-glucan without breaking the starch granule. Differential scanning calorimetry and rapid viscosity analyses of the α-GCS confirmed that the α-glucan coating decreased the degree of retrogradation in the initial stage, and the starch retrogradation was significantly decreased to 23.1% after 5 weeks compared to the control. The results clearly suggested that physicochemical properties of raw NCS were improved by the α-glucan coating by the AS treatment on the surface. Thus, the newly synthesized α-GCS can be utilized as a functional material in the starch-based food industry for shelf-life extension via controlled retrogradation.