초임계 이산화탄소를 이용한 밀배아 oil의 효소적 에탄올화 반응 특성

Abstract

Enzymatic ethanolysis of wheat germ oil with immobilized lipase was investigated for enhancing the function of wheat germ oil. As an alternative to chemical hydrolysis, which is difficult to control, the biochemical ethanolysis by lipase is uncomplicated to carry out. Lipases are highly versatile and efficient bio-catalysts for these esterification reactions. With better reaction technologies, the by-products recovered from food processing can be turned into valuable products or at least converted into useful sources. It is possible to convert lipid to monoglyceride and diglyceride by enzymatic ethanolysis. Monoglyceride and diglyceride are widely used as emulsifiers in the food and medical supplies industry. Ethanolysis reactions were carried out in two different systems; non-pressurized and pressurized system. In non-pressurized system, the enzymatic ethanolysis was carried out in an erlenmeyer flask (25 ml) containing a mixture of wheat germ oil and 99.9% ethanol using 1-5 w% immobilized lipase as Lipozyme TL-IM and Lipozyme RM-IM (based on w/w wheat germ oil). The reaction mixtures were incubated at 40-70°C and shaken at 120 rpm. In pressurized system, the enzymatic ethanolysis was carried out at various condition; immobilized lipase concentration (2 w%), reaction time (24 hours), reaction temperature (40 - 60°C) and reaction pressure (75, 100, 150, 200 bars). The samples obtained from each fraction were analyzed by HPLC for analysing contents of monoglyceride, diglyceride, and triglyceride. The conversion of wheat germ oil increased with the reaction temperature and with the concentration of immobilized lipase. The optimum condition of enzymatic ethanolysis in non-pressurized and pressurized system was at 50°C of reaction temperature and 100 bar of pressure.