Submitted to: Global Aquaculture Advocate
Publication Type: Popular Publication
Publication Acceptance Date: August 10, 2006
Publication Date: July 20, 2008
Citation: Bower, C.K., Avena Bustillos, R.D., Olsen, C.W., Olson, D.A., Mc Hugh, T.H. 2008. Cost to Benefit - Fish Skin Yields Unique Gelatin Products. Global Aquaculture Advocate. 11(4):28-29. Interpretive Summary: Fish skins can be processed into food-grade gelatin. Unlike gelatins made from cattle and pig skins, those from coldwater fish remain liquid when not refrigerated. Fish skin gelatin's unusual functional properties may prove it useful as a binder, emulsifier and nutrient, as well as moisture and oxygen barrier for increasing the shelf life of foods and aquaculture feeds.
Technical Abstract: Gelatin is traditionally produced by hydrolysis of bones and skins from cattle and pigs. This can create problems for people with kosher and halal dietary restrictions, and also carries the potential of health hazards associated with outbreaks of bovine spongiform encephalopathy. The gelatins of coldwater fish skins differ from other gelatins in gel-set and melting temperatures. Skins from coldwater fish produce a gelatin that does not solidify at room temperature, making it difficult to directly substitute for gels prepared from the skins of cattle, pigs, and warmwater fish. This is actually an advantage, since it imparts unique functional properties that are not present in other gelatins. By-products such as fish skins from Alaska’s fishing industry represent an underutilized resource often subject to disposal costs rather than economic benefits. Currently, fish processing operations can mechanically separate skins from other fish components during the production of boneless fillets, making the collection of discarded skins economically feasible. These fish skins can be stabilized by various drying techniques without seriously hindering the yield and quality of extracted gelatin. Dried fish skins substantially decrease transportation costs and facilitate storage, perhaps eventually leading to widespread production of high-value fish skin gelatin of acceptable quality for food, aquaculture feeds and pharmaceutical uses.