Location: Bioproducts ResearchTitle: Modulating physicochemical properties of collagen films by cross-linking with glutaraldehyde at varied pH values
|ZHANG, TING - Jiangnan University|
|YU, ZHE - Jiangnan University|
|YUN, MA - Jiangnan University|
|LIU, FEI - Jiangnan University|
|ZHONG, FANG - Jiangnan University|
Submitted to: Food Hydrocolloids
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/9/2021
Publication Date: 10/11/2021
Citation: Zhang, T., Yu, Z., Yun, M., Chiou, B., Liu, F., Zhong, F. 2021. Modulating physicochemical properties of collagen films by cross-linking with glutaraldehyde at varied pH values. Food Hydrocolloids. 124. Article 107270. https://doi.org/10.1016/j.foodhyd.2021.107270.
Interpretive Summary: Collagen films can be used as casings for sausages, but have low strength and poor stability at high temperatures. The films can be cross-linked with glutaraldehyde at different pH values to improve their mechanical properties. Cross-linking under acidic or low pH conditions resulted in films with slightly improved mechanical properties. However, cross-linking under alkaline or higher pH conditions resulted in greatly improved mechanical properties. Consequently, the mechanical properties of the films can be tailored by varying the pH of the cross-linking reaction.
Technical Abstract: Collagen films cross-linked with glutaraldehyde (GTA) at different pH values were prepared to explore the influence of pH on their physicochemical properties. The films were characterized using FTIR spectroscopy, XRD analysis, SDS-PAGE, shrinkage temperature, fluorescence analysis and SEM. The results indicated that crosslinking degree and reaction position were different at different pH values. The optimal cross-linking degree in collagen films was obtained under neutral and alkaline conditions. The main reaction under acidic conditions was intramolecular cross-linking and this gradually shifted to intermolecular cross-linking with an increase in pH. Cross-linked films had improved mechanical properties and thermal stability as well as higher b* values compared to films without cross-linking. These improvements correlated with the degree and position of crosslinking reactions. Controlling the reaction pH can be used to modulate the physicochemical properties of the collagen films to match specific application requirements.