Comparison of the physicochemical quality of tuna bone gelatin extracted using aren vinegar with commercial gelatin

Gelatin is a protein derivative of collagen that is denatured through a heating process preceded by a pre-treatment process using a base or acid. Acid solutions commonly used in pre-treatment are synthetic acids such as hydrochloric acid, acetic acid and citric acid. However, in this study, natural acid from the fermentation of nira water, namely aren vinegar, was used. This study aims to characterize the physiochemical properties of tuna bone gelatin soaked in aren vinegar for 25 days (Gl) and 35 days (G2) and compare it with commercial fish bone gelatin (CG). The data obtained were analyzed by the Independent T-Test at a 95% confidence level. The results showed that differences in soaking time affected the yield, color degree, viscosity, moisture content, ash, fat, protein and amino acid profile of gelatin. The yields of Gl and G2 were 7.42% and 5.20% respectively, protein were 72.31% and 81.74% respectively, lower than CG with 92.34%, and viscosity was 8 mPaS and 11.83 mPaS respectively, higher than the CG viscosity of 4 mPaS. Gl and G2 met the moisture content requirements based on GMIA (2019) in the range of 8-13%, but not CG. The average amino acid composition of Gl was lower than G2 and CG and had the lowest brightness level. The pH of Gl and G2 was not significantly different and each was significantly different from CG.