The characteristic of gelatin extracted from the skin of adult and sub-adult striped catfish (Pangasius hypophthalmus) using acid-base pretreatment: pH and FTIR

The gelatin is the biomaterial that produced by collagen denaturation. The age of animal was reported influences the collagen crosslinks which by that contribute to the gelatin quality. The aims of this study were to determine the characteristics of gelatin that extracted from the skin of adult and sub adult striped catfish (Pangasius hypophthalmus) using acid-base pre-treatment based on pH and FTIR (Fourier Transform Infrared) analysis. The gelatine were extracted from striped catfish skins of adult fish (total body length or TBL= 48.6 ± 1.9 cm) and sub-adult (TBL =38.9 ± 0.5 cm) using acid-base pre-treatment (CH3COOH and NaOH solution). The pre-treated skin was washed with tap water until neutral. Finally, the swollen skin was mixed with sterile water at a ratio 1/10 (w/v) and extracted using water bath at 40-70 °C for 60 minutes. In general, the pre-treated acid-base of adult and sub adult fish skin resulted the neutral pH gelatin. The FTIR spectra analysis of gelatin from adult and sub adult striped catfish skin exhibited the similar of wavenumbers included amide A, B, I, II, and III region. In both striped catfish skin gelatin adult and sub-adult were shown the functional groups of O-H, C-H, N-H, C = O, C = N, C = C, and N = O.