การสกัดและทำให้บริสุทธิ์ของเจละตินจากเศษหนังสัตว์ใหญ่ที่ยังไม่ผ่านการฟอกโดยใช้แอลคาไลน์โปรทีเอส / ปาริชาติ ลบแย้ม = Extraction and purification of gelatin from raw hide waste using alkaline protease / Parichat Lobyaem
This research focused on the extraction and purification of gelatin from raw hide waste using alkaline protease (Savinase 12T). The effect of extraction conditions including enzyme concentration (0-10,000 U/mg), time (20-180 min), temperature (40-60 °C) and pH (8-11) on the properties of gelatin was investigated. The results were then analyzed by a statistical program, Duncan's New Multiple Range test, to determine the extraction factors that significantly affected the important properties of gelatin, e.g. gel strength and viscosity, The analyses showed that enzyme concentration, time, temperature, pH and their interaction affected the gel strength at 95% confident level and the gel strength ranged between 4.6-165.8 g Bloom. In case of viscosity, only time, temperature, pH and their interaction significantly affected the viscosity which ranged between 1.59-3.07 cP. In the purification study, it was found that the molecular weight of gelatin varied directly with the gel strength and viscosity. The higher the molecular weight higher the gel strength and the viscosity. The molecular weight of gelatin was in the range of 100 K Da, which was corresponded to the gel strength and the viscosity of 160 g Bloom and 3.00 cP respectively. Chemical and physical properties of gelatin including solubility, pH, color, amount of As, Cu, Pb, S, Zn, moisture, fat, and colony forming unit were tested. The results showed that all properties were approved by Thai Industrial Standard of gelatin. Finally, the analysis of amino acid composition showed that the main components of gelatin were 26% glycine, 15% proline, 11% glutamic acid, 10% arginine, 9.9% alanine, 6% aspartic acid and 22.1% other amino acids.