Study On Extraction Of Red Pigment From Jujube Date Var. Muzao Rind And Stability Of The Pigment

Jujube date is the fruit of Ziziphus jujube mill plant of Rhamnaceae. It contains many effective components, such as amino acid, vitamin, polysaccharide, flavonoid, saponin, all that can strengthen immunity, postphone senescence, protect from vascular sclerosis, etc. With the increase of people's life level and deep knowledge of safety about edible synthetic pigment, the role of the edible natural pigment is more prominent because of its higher safety. Therefore, study on extraction of red pigment from jujube date rind and stability of the pigment is also valued.This paper mainly studied three aspects. The first aspect studied technical conditions of solvent extraction and supersonic extraction of red pigment from jujube date. The second aspect studied the purification of the red pigment. The third aspect studied the stability of the semifinished and purified pigment under different circumstances.The main results were as follows:1) The extractor of solvent extraction and supersonic extraction were NaOH.2) The optimum extraction conditions of solvent extraction were concentration of extractor 1.0%, extraction temperature 75℃, material/extractor ratio 1:20, extraction time 2.5h, time of extraction 2 times. In the conditions the yield of the extracted pigment reached 92.99%.3) The optimum extraction conditions of supersonic extraction were supersonic time 25min, supersonic power 300W, concentration of extractor 0.9%,material/extractor ratio 1:25, time of extraction 3 times. In the conditions the yield of the extracted pigment reached 94.08%.4) The concentrated solution of the pigment was purified by silica-gel column chromatography. The solvents of desorption were solutions of 70% and 80% methanol in ethyl acetate, 90%, 80% and 70% methanol in turn. The purified pigment colourity reached 24.5) The experiments on the purification of the pigment showed: (1) The stability of the pigment was enhanced after purification.(2) The pigment was not stable and was precipitated easily under acid conditions. But its stability was enhanced under basic conditions and the colour of its...