The Study Of Lycopene About Its Technological Process Of Extraction And Purification And Its Stability

Lycopene is a kind of natural carotenoid, it has the function of various health cares, such as resisting cancer, increasing the immunity and deferring decrepitude etc. The paper mainly studies the technologic processes and conditions by which oleoresin be extracted from natural tomatoes then be purified into lycopene crystal.Alkaline saponification can remove the glyceride and fatty acid, and release lycopene. Under the protection of tomato cell tissue lycopene will not denature. The best conditions of tomato saponification are temperature 70 C, concentration of KOH 0.5 mol/L and time 0.5h.The lycopene oleoresin extracted from sapnification tomato included some crystal, and its color value increased to 66.7The methods including solid-liquid leaching, soxholet extraction and microwave extraction have been utilized to gain crude product from dry tomato powder with petroleum benzene. The factors such as temperature, time, ratio of liquid-solid, microwave power will affect the amount of oleoresin. The result shows that the best conditions of solid-liquid leaching are temperature 50-60 C, time Ih, ratio of liquid-solid 40:1,and the amount of oleoresin is 22.54mg/g (tomato powder); the best conditions of soxholet extraction are temperature 45 C, time 4h, ratio of liquid-solid 100:1,and the amount of oleoresin is 22.69mg/g (tomato powder); the best conditions of microwave extraction are power 400w, time 60s, and the amount of oleoresin is 22.54mg/g (tomato powder). The comparation of the three methods proves that microwave extraction can be used in industrial production of lycopene because of its high efficiency and output.Oleoresin can be purified by column-chromatography. The immobile phase is silica-gel and the mobile phase is the mixture of V (hexane): V (acetone)=1.5:1. The result of optimization for column-chromatography condition proves that the best flow speed of immobile phase is 5ml/min, and the ratio of height-diameter is 30:1. The needle crystal can be gained from the concentrated eluting liquid, and the measurement by HPLC shows that the masspercentage of lycopene is 18.9%. Other ingredients separated from oleoresin are B-carotene and lutehi.Light, oxide, temperature and acid salt tolerance will affect the stability of lycopene. The degree of lycopene denaturalization is often different from the state in which lycopene exists. Oxide denatures tomato powder more evidently and light affects the stability of lycopene solvent more distinctly.