Abstract:

The hot water extraction of collagen from tilapia skin was optimized using Box-Behnken design and response surface methodology and the collagen was analyzed for its physicochemical properties. The optimum conditions for the improved extraction of collagen from tilapia skin were determined as follows: soaking tilapia skin in 0.213 mol/L HCl solution with a ratio of material to liquid of 1:20 (m/V) at 4 ℃ for 21 min prior to the hot water extraction with a ratio of material to liquid of 1:7 (m/V) at 42 ℃ for 12.6 h, and the optimized extraction led to a collagen content of 293.018 mg/g. The collagen was rich in glycine, proline and hydroxyproline. SDS-PAGE analysis showed that this collagen contained α1, α2 and β chains indicating that it is a typical type I collagen. Its gel strength and characteristic viscosity were 682 g and 1.461dl/g, respectively.

Key words: tilapia skin, collagen, hot water extraction, gel strength, characteristic viscosity