Acetylated rice starch nanocrystals improved the physical, mechanical, and structural properties of native rice starch based films

• Published in: International journal of biological macromolecules 2023-12, Vol.253, p.127271-127271, Article 127271
• Main Authors: Yang, Fan, Wei, Yujun, Xiao, Huaxi, Zhang, Qian, Li, Jiangtao, Lin, Qinlu, Zhu, Dekun, Huang, Zhengyu, Liu, Gao-Qiang
• Format: Article
• Language: English
• Subjects: Acetylated starch nanocrystals; Film property; Nanocomposite films; Starch nanocrystals
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2023.127271

Rice starch nanocrystals (SNC) and acetylated rice starch nanocrystals (ASNC) with three different substitution degrees (DS) for 0.22 (ASNCa), 0.56 (ASNCb), and 0.83 (ASNCc), respectively, were synthesized. Starch nanocrystals (SNC, ASNCa, ASNCb and ASNCc) with varying concentrations (0–25 %) were used in the production of composite rice starch-based films plasticized with glycerol using the solvent casting technique. Films were compared concerning their morphology, moisture content and solubility, transmittance, tensile strength, elongation at break. The SNC and ASNC content and acetylated DS had a significant effect (p ≤ 0.05) on all the properties investigated when compared to the control film. The addition of ASNC resulted in less hydrophilic films and UV light barrier properties, and the addition of SNC and ASNC increased the rigidity of starch film. There was an increase of 156.7 % in tensile strength for 10 % ASNCc composite films and a reduction of 68.1 % in water vapor permeability for 20 % ASNCc composite films. The rice starch/ASNCb nanocomposite films with the addition of 5 % and 10 % ASNCb exhibited a compact, smooth, and flat surface structure. Therefore, these results showed that ASNC significantly improved the mechanical properties, surface morphology and thermal stability of the films. •Rice starch nanocomposite films were synthesized by incorporating with ASNC•The films added with ASNCb got a compact, smooth, and flat surface structure•The water solubility of the films decreased with increase in the concentration of ASNC•ASNC improved the mechanical properties and thermal stability of the films