| In this paper we cheese Nanyang gray wheat which is one kind of Nanyang color wheat for raw material, try the material directly with the skin of Nanyang gray wheat .A study was conducted to determine the best extraction condition, superficial purification and the physical and chemical properties. Then provided a reference for a development in many ways of Nanyang color wheat and gist for development about natural pigment from Nanyang gray wheat.Details are as follows:(1)Study on the best extraction conditionBy the single factor experiments and by the single factor experiments with hand over to experiment of synthesize the analysis, we concluded: the best apparatus was ultrasonic; extraction temperature: 50℃, extraction time:50min, material rate: 1: 25 (m/v),the best impregnant was acidic ethanolt(50+6,v+v).(2) Study on the the physical and chemical propertiesA study was conducted to determine the stability of the pigment.①High temperature above80℃and sunlight,the pigment was destroyed srongly; H2O2 and Vc could affect the stability of the pigment; High concentration Cu2+ and Fe3+ would affect the stability of the pigment.②lower than 60℃in short time, the stability of the pigment could maintain;Other metal ions in permitted usage level would not affect the stability of the pigment Under 2.0×10-3mol/l except Cu2+and Fe3+; Under the concentration of 2.5% about citric acid , the stability of the pigment could just maintain;Under the concentration of 0.5%Na2SO3, the retention of the pigment was 85% above in a week; Under the concentration of 2%NaCL,the change was just 8.00 %.③Keep in the refrigerator of 4℃, reserve the rate to still be up to 92.36% after half a year;Under the condition of prevention sunlight, or pH< 5, the stability of the pigment could maintain;Under the concentration of 5% about sugar, the stability of the pigment could maintain;Under the concentration of 1.0% about Sodium Benzoate, the retention was up to 90%.④Al3+ could increase the absorbance,but the color did not change obviously.(3) Study on the the uperficial purificationThrough the experiment about the adsorption of macroporous adsorption resin, we had selected XDA-5 as the best resin. The best adsorption condition included: adsorption temperature:room-temperature,pH1-3,concentration:0.6302(absorbance),Saturationtime:24h( A=0.6342).(4) The qualitative analysis about the pigment when had been purificatedThe spectrophotometer charomatogram of the pigment indicated that there was a absorption peak at 542nm.The pigment deposited when met lead Acetate,could be adsorbed by active carbon. And its coler changed when the pH changed,So we can concluded:the pigment from Nanyang gray wheat might be the pigment fromAnthocyanins.
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