Characteristics and Functional Properties of collagen extracted from Nile tilapia (Oreochromis niloticus) skin

Abstract

: Tilapia skin might be used as a new source of collagen, therefore collagen extracted from Nile tilapia skin can be utilized as food products because of its good functional properties. Two extraction methods were used to obtain acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) from Nile tilapia skin. In this study, collagen was characterized in terms of FT-IR Spectrum, amino acid analysis, SDS-PAGE and Thermal denaturation temperatures (Td). Also, some major functional properties including solubility, oil and water absorption, emulsifying activity and stability, foaming ability, foam stability, and gelation properties were determined. The results showed that the yields of ASC and PSC were 4.30% and 1.84 % (on a wet weight basis), respectively. Amino acid composition analysis indicated that the imino acid content of ASC and PSC were found to be 172.10 and 164.18 residues per 1000 residues, respectively. SDS-PAGE results indicated that ASC and PSC were type I collagen. The FTIR Spectrum confirmed that the presence of a triple-helical structure characteristic of ASC and PSC. The denaturation temperature of ASC and PSC were 26⁰C and 25⁰C respectively. The solubility of ASC and PSC were highly solubilized in the pH range of 2–3. ASC and PSC had good water and oil absorption capacity. Gelation studies revealed that ASC and PSC have good gelation properties. Consequently, Nile tilapia skin could be used as a good source to extract ASC and PSC which can be used to add high value in the food industries.