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Safe and reliable natural pigment, natural color, gradually become the main food colorants trend to replace synthetic pigment, natural pigments extracted from the jujube, not only can be used in food coloring, add new varieties to the natural pigment of red dates comprehensive development and utilization, increase the added value and economic benefits of positive significance. This thesis, the red pigment in red dates extraction, purification, stability, chemical structure and the application of systematic research, and provide a theoretical basis for the extraction and purification of jujube red pigment to achieve industrialization. Solvent and ultrasonic assisted extraction of jujube red pigment, solvent optimum conditions: particle size of 40 mesh, temperature 80 ° C, the solid to liquid ratio of 1:20, concentration of NaOH 0.2mon / L, extraction time 3h extract Series 3, the extraction rate of 95.98%; optimum conditions of ultrasonic assisted method of ultrasonic power 60W, time 45min, temperature 60 ° C, solid-liquid ratio of 1:20, extract the order of two extraction rate 94.58%. The macroporous research: S-8 macroporous resin purification effect. The experimental conditions were: a pH of 12, a room temperature adsorption, eluent 0.2mol/LNaOH, adsorption flow rate of 1mL/min, the desorption flow rate is 1mL/min. Jujube red pigment purified in the above optimized conditions, the yield up to 6.36%, the the purified pigment color bid was not purified about 10 times. The stability test results show that: jujube red pigment is preferably on the temperature and illumination stability; relatively stable under alkaline conditions; metal ion K, Ca2, Na, Mg2, Zn2 showed good stability, and K, Ca2 low concentration of H2O2, Na, Mg2, Zn2 pigment hyperchromic while Cu2, A13, Fe3 pigment has obvious destructive, jujube red pigment should avoid contact with iron, copper and aluminum containers; jujube stability of red pigment was less affected, the impact of the higher concentration of pigment oxidation resistance is not very good. Jujube red pigment of the poor stability of ascorbic acid and citric acid, better stability of sodium sulfite; sodium benzoate and sucrose on the stability of the pigment are small. By jujube red pigment color reaction and ultraviolet, infrared spectroscopy scanning, we can see the red dates red pigment the flavonoids containing = C-OH, aromatic ring C = O structure. By the red pigment in red dates, high temperature and light experiments with temptation red the Monascus contrast, show that it has better application performance, and applications in the food industry.
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