Extraction of gelatin from red tilapia (oreochromis nilotica) skin

Gelatin is a functional protein that widely used in food industry to improve elasticity, consistency and stability. It can be extracted from the skin, scales and bones of fishes to provide the alternative sources for Muslim and Jews consumers. Gelatin from the skin of red tilapia fish (Oreochromis nilotica) treated with 0.2% sodiums. hydroxide (NaOH), soaked in 0.2% sulphuric acid and 1.0% citric acid. Later, gelatin extracted from the treated skins with distilled water at 45°C for overnight. The extracted gelatins were filtered, centrifuged and evaporated. The gelatin obtained was in white and soft-textured powder in appearance and there was slightly detectable fishy odour as dried powder. The concentration of glycine in the extracted gelatin was determined by using high performance liquid chromatography (HPLC). The extracted gelatin was hydrolyzed with hydrochloric acid (HCI) before injected into the column of HPLC. The concentration of glycine in extracted gelatin is 85.58 mg/mL.