火龙果色素在不同体积分数乙醇溶液中的稳定性  

Stability of pigments from pitaya in different volume fraction of ethanol

作　　者：叶丽君[1] 邵伟琪[1] 王兴莉[1] 黄雪松[1] 

机构地区：[1]暨南大学理工学院食品科学与工程系,广东广州510632

出　　处：《暨南大学学报（自然科学与医学版）》2012年第5期477-480,共4页Journal of Jinan University(Natural Science & Medicine Edition)

基　　金：国家科技支撑计划项目(2012BADB0301);暨南大学本科生科技创新工程项目(cx11026)

摘　　要：为研究火龙果色素在不同体积分数的乙醇溶液中的稳定性,以吸光度变化为指标,探讨火龙果色素在pH 5.0时,不同乙醇体积分数在不同温度条件下的稳定性.结果表明:乙醇不影响火龙果色素的紫外可见吸收光谱.在40℃和80℃时,火龙果色素降解符合一级反应,其降解速率常数k随着乙醇体积分数的升高而增大,其稳定性降低;而在4℃时,火龙果色素在乙醇溶液中的稳定性较好,其中在体积分数为0、16%、30%的乙醇溶液中稳定性较在体积分数为60%的乙醇溶液中好.此研究结果为含醇火龙果饮料的稳定性提供参考依据.To investigate the stability of pigments extracted from purple pitaya （ Hylocereus polyrhizus） in the ethanol solutions, the degradation of pigments in 0, 16%, 30% and 60% ethanol at pH 5.0 have been monitored by the change in spectroscopic absorption under the temperature of 4 ℃, 40 ℃ and 80 ℃, respectively. The maximum absorption of the extracted pigments in the given concentrations of ethanol kept constant at 534 nm. The degradation of the pigments followed first-order kinetics reaction and the rate constants raised with the increase in the temperature of ethanol from 40 ℃ to 80 ℃. Moreover, the pigments exhibited better stability in 0, 16% and 30% ethanol solutions than that in 60% ethanol. Taken together, these results could provide scientific information for evaluation of the stability of pitaya wine.

关 键 词：火龙果 乙醇 稳定性 色素 

分 类 号：TS201.2[轻工技术与工程—食品科学]