Characteristics and Gel Properties of Gelatin from Goat Skin as Affected by Extraction Conditions

Characteristics and gel properties of gelatin from goat skin, as influenced by extraction conditions, were studied. Yield of gelatin was 22.1–23.1% (wet weight basis). All gelatins contained α-chains as the predominant components, followed by β-chain. However, no β-chain was retained when extracted at 70C. Gelatin extracted at 50C for 2.5 h exhibited the highest gel strength (267 g) (P < 0.05). Gelling and melting temperatures for goat skin gelatin were in the ranges of 21.18–25.17C and 30.69–34.12C, respectively. Gel strength, gelling and melting temperatures of gelatin gels generally decreased with increasing extraction temperatures and times. Gels of gelatin extracted at a higher temperature for longer time had larger strands and voids. Gelatin extracted at 50C for 2.5 h contained imino acids of 225 residues/1,000 residues and showed higher gel strength than bovine gelatin. Thus, it could be used as a potential replacer for commercial gelatins. Practical Appications: Gelatin has been used in food and non-food industries all over the world. With increasing demand of gelatin, particularly as the halal ingredient, the promising alternative raw material has been searched. Goat skin has become the potential collagenous starting material; however, the extraction conditions must be optimized to obtain the good quality gelatin. Therefore, gelatin from goat skin with properties equivalent to commercially available bovine or porcine counterparts can be produced and the goat skin can be better exploited.