The relationship between molecular structure and film-forming properties of thermoplastic starches from different botanical sources

• Published in: International journal of biological macromolecules 2023-03, Vol.230, p.123114-123114, Article 123114
• Main Authors: Yang, Na, Gao, Wei, Zou, Feixue, Tao, Haiteng, Guo, Li, Cui, Bo, Lu, Lu, Fang, Yishan, Liu, Pengfei, Wu, Zhengzong
• Format: Article
• Language: English
• Subjects: Amylopectin; Amylose - chemistry; Chemical Phenomena; Film-forming characteristics; Molecular Structure; Pisum sativum; Starch - chemistry; Starches from different botanical sources
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2022.123114

To illustrate the correlations between molecular structures and the film-forming properties of thermoplastic starch from various botanical sources, starches from cereal, tuber and legume were modified by thermoplastic extrusion and the corresponding thermoplastic starch films were prepared including thermoplastic corn starch (TCS), thermoplastic rice starch (TRS), thermoplastic sweet potato starch (TSPS), thermoplastic cassava starch (TCAS) and thermoplastic pea starch (TPES) films. TPES film displayed a higher tensile strength (6.28 MPa) and stronger water resistance, such as lower water solubility (15.70 %), water absorption (42.35 %), and water vapor permeability (0.285 g·mm·h−1·m−2·kPa−1) due to higher contents of amylose and B1 chains. TCAS showed a smoother and more amorphous film due to higher amylopectin content, resulting higher elongation at break and larger opacity. TCS film was the most transparent due to a compacter network and more ordered crystallinity structure, which was suit for the packaging of fresh vegetables and aquatic products, whereas TCAS film was the opaquest, which protected package foods from light such as meat products, etc. The outcome would provide an innovative theory to regulate accurately the functional properties of thermoplastic starch films for different food needs. •The structure-function relationship of thermoplastic starch films was studied.•TPES film with higher contents of amylose and B1 chains displayed a stiffer structure.•TPES film displayed a stronger water resistance with higher amylose content and B1 chains.•TCAS film with higher amylopectin showed a higher elongation at break and opacity.•TCS film was the most transparent due to more ordered crystallinity structure.