Location: Bioproducts ResearchTitle: Calcium spraying for fabricating collagen-alginate composite films with excellent wet mechanical properties
|MA, YUXIN - Jiangnan University|
|MA, YUN - Jiangnan University|
|YU, ZHE - Jiangnan University|
|LIU, FEI - Jiangnan University|
|ZHONG, FANG - Jiangnan University|
Submitted to: Food Hydrocolloids
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/4/2021
Publication Date: 11/9/2021
Citation: Ma, Y., Ma, Y., Yu, Z., Chiou, B., Liu, F., Zhong, F. 2021. Calcium spraying for fabricating collagen-alginate composite films with excellent wet mechanical properties. Food Hydrocolloids. 124. Article 107340. https://doi.org/10.1016/j.foodhyd.2021.107340.
Interpretive Summary: Collagen films are used as casing for sausages, but are not as elastic as natural casings. The mechanical properties of the collagen films can be improved by dipping in alginate solution and then cross-linking with calcium ions. Two different methods of adding calcium to the film were examined in this study: addition before the film was dry after dipping and addition after the film had dried. Addition of calcium before drying resulted in films with improved mechanical and water resistant properties. In comparison, addition of calcium after drying resulted in films with improved mechanical properties and undisturbed collagen structures.
Technical Abstract: Two spray processes for adding calcium were designed to improve the mechanical properties of collagen fiber films in wet conditions. The processes were applied after immersion of the films in sodium alginate (SA) and glycerol solution. One process (P1) involved spraying after immersion but before the film had dried the film and the other process (P2) involved spraying after drying the film. Both processes significantly improved the wet mechanical properties of the films. However, P1 mainly enhanced the elasticity and stiffness, whereas P2 mainly enhanced the toughness. Ca-alginate complexes gradually formed in the samples after the addition of Ca2+, improving the water resistance of the samples. For the samples prepared using P1, Ca2+ penetrated inside the film and chelated SA and collagens to form a dense network, but further damaged the triple helix structures of collagens. For the samples prepared using P2, the sprayed calcium ions generated a protective layer of calcium alginate on the surface of the membrane and the secondary structure of the collagen was better maintained.