【摘要】 通过对磨盘柿果实色素的乙醇提取液进行不同处理 ,对果实色素的稳定性进行了研究。在阳光直射 5d以内、室内自然光照射 2 5d以内或在室内避光保存 30d以内的条件下 ,磨盘柿色素在可见光区的最大吸收波长未发生改变 ,但吸光值降低 ,柿色素保留率在 6 0 %以上 ;80℃以上的高温对柿色素有破坏作用 ,但 6 0℃ ,2h以内的高温条件下柿色素的稳定性良好 ;柿色素溶液在pH 6～ 11范围内呈稳定状态 ;供试的 9种金属离子中 ,铁离子对柿色素的稳定性影响最大 ,0 12 5mmol·L-1以上的铁离子使柿色素溶液变浑浊 ,出现沉淀 ,Cu2 + ,Ca2 + 和K+ 次之 ,而Al3 + ,Na+ ,Zn2 + 和Mg2 + 影响较小。质量分数为 1%的苯甲酸钠和山梨酸钾对柿色素稳定性影响不大 ;而质量分数为 2 %的VC对柿色素有保护作用。在加工利用和保存柿色素时 ,需提供有利柿色素的稳定条件 ,才能保持柿色素的营养价值。更多还原

【Abstract】 The pigment solution of persimmon(Diospyros kaki. cv. Mopanshi) fruit was extracted by ethanol and used to determine the pigment stability under different conditions. Sunshine exposure for 5?d, indoor natural sunlight exposure for 25?d, and dark room storage for 30?d did not alter the maximum absorbance wavelength of pigment, but lowered the absorbance value. More than 60% of the pigment was still in the solution. The pigment was destroyed at the temperature higher than 80?℃, but stable at 60?℃ for 2?h. The pigment solution was stable at pH 6～11. Of the tested 9 metal ions, ferric ion (Fe 2+, Fe 3+) precipitated pigment at a concentration of 0.125?mmol·L -1. The cations of Cu 2+, Ca 2+, K+ had significant impacts on the pigment solution stability. In contrary, Al 3+,Na+, Zn 2+, and Mg 2+ had little influence on the solution stability. One percent of the sodium benzoic acid and the potassium sorbic acid had no effect on pigment stability, but 2% ascorbic acid had some protective effect. The results indicated that effective utilization of persimmon pigment could only be achieved under optimal conditions.更多还原