The Effect of Ultrasonication Time on Gelatin Characteristics of Cobia Fish (Rachycentron canadum) Skin

Cobia skin is still rarely used as a raw material for gelatin production, even though this fish contains a certain amount of collagen which can be a promising source of gelatin. Ultrasound can be used as an alternative to assist the gelatin extraction process when applied with an appropriate time duration. The purpose of this study was to determine the effect of ultrasonication time on the gelatin characteristics of the cobia skin and determine the best ultrasonication time treatment based on its gel strength and viscosity. The research method used was an experimental laboratories with a Complete Randomized Design (CRD) pattern with ultrasound time of 20 minutes, 40 minutes, and 60 minutes and control treatment. The data were analyzed using ANOVA and further analysis of Honestly Significant Differences (HSD) was carried out to determine the differences in treatment. Each treatment was repeated 3 times. The results showed that the ultrasonication treatment affected all gelatin parameters of cobia skin gelatin. Some parameter values at ultrasonication treatment were lower than control treatments such as protein content, moisture content, ash content, and pH, but the yield, gel strength, and viscosity parameters tend to improve as the ultrasound time increases. The ultrasonication treatment for 40 minutes was the best treatment to produce cobia skin gelatin with the highest gel strength and viscosity of 391.40 bloom and 7.33 cP.