Citric acid crosslinked soluble soybean polysaccharide films for active food packaging applications

• Published in: Food chemistry 2024-04, Vol.438, p.138009-138009, Article 138009
• Main Authors: Liu, Jie, Dong, Yitong, Zheng, Xuejing, Pei, Ying, Tang, Keyong
• Format: Article
• Language: English
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2023.138009

In this work, a nontoxic crosslinking agent, citric acid (CA), was used to crosslink glycerol-plasticized SSPS films via a heat activated reaction. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy results confirmed the occurrence of esterification reaction between CA and SSPS. Microstructure of the CA-crosslinked SSPS films were characterized by scanning electron microscopy, atomic force microscopy and X-ray diffraction. The water resistance, mechanical, UV-barrier, water vapor barrier, antioxidant and thermal properties of SSPS films were enhanced by CA crosslinking. The SSPS film crosslinked with 5 % CA exhibited a maximum tensile strength of 6.5 MPa and a minimum water solubility of 34.3 %. The CA-crosslinked SSPS film also presented superior antibacterial properties against Gram-positive and Gram-negative bacteria. Application test results showed that the CA-crosslinked SSPS film can effectively delay the oxidative deterioration of lard during storage, suggesting that the developed CA-crosslinked SSPS film could be a promising candidate for active food packaging.