Edible Gelatin from Some Fishes Skins as Affected B Y Chemical Treatments

Gelatin isolated from limed split wastes can be a high value product due to its special characteristics and has many potential future applications in Food, functional additives, Food and pharmaceutical industries. Concentrations of sodium hydroxide, sulfuric and acetic acids used in processing gelatin from Narrow barred, Carcharhinus Leucas, Siganus Sutor and Indo Pacific king mackerel skins affected yield. The highest yield of gelatin was obtained when concentrations 3.5%(w/v} of sulfuric acid and sodium hydroxide were applied to the skins followed by treatment with 4%(w/v) acetic acid. The highest yield depends on varieties of fish and the content of collagen exist in fish skins. Gelatin yield of Siganus Sutor skins was shown to be high in comparison with of Indo Pacific king mackerel. Gelatin yield of Narrow barred skins was shown to be high in comparison with others samples. The high yield depends on used chemical compounds concentrations and varieties of fish. Therefore, from the economic point of view, extraction of gelatin from Siganus Sutor, Narrow barred and Indo Pacific king mackerel skins was shown to be suitable. In conclusion, practical application is about to change fishery wastes into valuable edible protein(Gelatin) so that gelatin will used in food industries and other industries as Photographic gelatin and industrial gelatin.