Effectiveness of Alkaline Pretreatment and Acetic Acid Hydrolysis on the Characteristics of Collagen from Fish Skin of Snakehead

Abstract

<p>Fish skin is one of marine byproducts potential for alternative source of collagen. This study<br />investigated the effectiveness of alkaline and acetic acid pretreatment on the characteristics of<br />collagen from skin snakehead fish. The concentrations of alkaline pretreatment were 0.05; 0.1; 0.15<br />and 0.2 M for 2, 4, 6, 8, 10 and 12 hours, acetic acid concentrations were 0.05 M, 0.1 M, 0.15 M and<br />0.2 M for 1 and 2 hours. The experimental design used for alkaline and acetic acid pretreatment<br />was factorial completely randomized design. The result showed that the concentration of alkaline<br />0.05 M for 6 hours have significant effect on the elimination of non-collagen protein (p<0.05),<br />whereas for the optimum acetic acid at a concentration 0.1 M for 2 hours significantly different<br />on solubility and swelling. Extraction yields of collagen was 16%, with characteristics of whiteness<br />66.67%, protein content 96.21%, viscosity 10 cP, Tmax 159.9oC and glass transition temperature<br />78.55oC. The dominant amino acid composition were glycine (27.11%), proline (13.87%) and<br />alanine (12.58%). Functional groups collagen from skin snakehead fish has β-sheet structure<br />which is a characteristic of collagen.</p>