Submitted to: Journal of American Leather Chemists Association
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/28/2004
Publication Date: 4/1/2005
Citation: Taylor, M.M., Marmer, W.N., Brown, E.M. 2005. Characterization of biopolymers prepared from gelatin and sodium caseinate for potential use in leather processing. Journal of American Leather Chemists Association. 100(3):149-159. Interpretive Summary: There has been considerable interest recently in the use of products from renewable resources for the production of goods that were customarily made from petroleum feedstuffs. Prior research from this laboratory demonstrated that gelatin, a by-product from the manufacture of leather, could be treated with enzymes to give products with superior functional properties. In this present study, we enzymatically combined gelatin with varying amounts of another sustainable resource, sodium caseinate from the dairy industry, to form biopolymers. These products have the advantage of possessing the unique properties of each protein and have the potential for generating novel products. We examined individually the properties of enzymatically modified gelatin and sodium caseinate, as well as their combined products. The properties of the gelatin biopolymers were enhanced by addition of even small amounts of the secondary protein, sodium caseinate. These distinctive reactions have the potential of generating products that could be used in leather processing, more specifically in preparation of coatings or as fillers for the leather, as well as being a solution to utilization of by-products from the leather and dairy industries.
Technical Abstract: Biopolymers formed from crosslinking of different proteins is an area of growing interest. Much has been reported in the literature on the properties of a variety of biopolymers synthesized by enzymatic treatment. These products have the advantage of possessing the unique properties of each protein and have the potential for generating novel products. Prior research from this laboratory demonstrated that gelatins of varying qualities could be enzymatically modified to give products with superior functional properties. SDS PAGE showed that these modified gelatins were highly polymerized, as demonstrated by an increase in higher molecular weight species. In this study, we examined individually the properties of modified proteins from renewable resources, specifically gelatins and casein, as well as their enzymatically combined products. The viscosities, gel strengths, and molecular weight distributions of the gelatin conjugate products show that the degree of crosslinking was enhanced by addition of even small amounts of the secondary protein. These unique reactions have the potential of generating products used in leather processing, more specifically in preparation of coatings or as fillers for the leather.