• 食品化学 •

### 食用级淀粉纳米颗粒乙酰化疏水改性及其消化特性

1. （广西民族大学化学化工学院，林产化学与工程国家民委重点实验室，广西林产化学与工程重点实验室/协同创新中心，广西多糖材料与改性重点实验室，广西 南宁 530006）
• 发布日期:2022-07-01
• 基金资助:
国家自然科学基金地区科学基金项目（21766004）；广西自然科学基金项目（2019GXNSFAA185008）

### Hydrophobic Modification of Food-Grade Starch Nanoparticles by Acetylation and Its Digestion Characteristics

YAO Xianchao, SHI Yonggui, JIAO Siyu, WU Yashan, YANG Wanyan, LIN Rihui

1. (Key Laboratory of Chemistry and Engineering of Forest Products, State Ethnic Affairs Commission, Guangxi Key Laboratory of Chemistry and Engineering of Forest Products, Guangxi Collaborative Innovation Center for Chemistry and Engineering of Forest Products, Guangxi Key Laboratory Cultivation Base for Polysaccharide Materials and Modifications, School of Chemistry and Chemical Engineering, Guangxi Minzu University, Nanning 530006, China)
• Published:2022-07-01

Abstract: Cassava starch nanoparticles with an average size of (273.8 ± 26.41) nm were prepared by ultrasonic crushing followed by ethanol sedimentation and were esterified with acetic anhydride to prepare hydrophobic nanoparticles. Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy showed that the degree of substitution (DS) of the esterified products was as high as 0.53 without adding any catalysts during esterification. X-ray diffraction (XRD) analysis showed that the crystal structure of starch nanoparticles did not change significantly after modification, and both the original and modified nanoparticles were amorphous. Scanning electron microscopy (SEM) showed that the morphology of the nanoparticles did not change significantly after modification. The three-phase contact angle increased with increasing DS, reaching a maximum of (109 ± 3.56)°, and the higher the DS, the longer the contact angle was maintained. The modified product was easier to disperse in the oil phase, leading to the formation of microemulsions. Surface modification changed the hydrophilic/hydrophobic properties of starch nanoparticles, and improved its potential for emulsification at the oil-water interface. In contrast to the unmodified sample, the modified sample showed similar enzymatic digestion curves and no fundamental change in eating quality, but lower enzymatic digestibility at the same time points, suggesting stronger resistance of the modified product with higher DS to enzymatic hydrolysis.