Gelatin extraction optimization from skin of sub adult and adult pangasius hypophthalmus

Fish skin is the potential gelatin source since the increase of the demand for the halal food due to the religious consideration. The yield of gelatin obtained from connective tissue of animal skin greatly affected by the extraction process and age of the animals that used as raw material. Research about the potential of the Pangasius hypophthalmus (striped catfish) skin as halal gelatin source have been developing. However, there was no information about the correlation between the length of striped catfish that representing age with the gelatin content. Here we optimize the gelatin extraction method from striped catfish skin with different length body size (sub adult and adult size) using statistical analysis of Placket Burman Design. We performed preliminary study to determine the variables used in the main study. We used 9 variables in the extraction process and analyzed the p-value of each variable. According to this analysis, three variables with the lowest p-values were selected: temperature (p=0.000); soaking time in alkali solution (p=0.055) and soaking time in acid solution (p=0.244). Range value of selected variables were determined according to the related previous studies. Results from our study showed that the maximum yield of sub adult and adult were obtained when we used 70°C as temperature of extraction, i.e. 37.42% and 30.31%, respectively. In general, sub adult striped catfish have higher yield than the adult one at the temperature of 40 and 70°C. However, the gelatin yielded from extraction process temperature of ≥70°C exhibited dark pigmentation, while the gelatin that obtained with temperature treatment of ≤ 55°C showed less pigmentation. The gelatin yielded from.