不同pH值条件下火龙果色素的降解动力学  

Degradation Kinetics of Pigments from Pitaya (Hylocereus polyrhizus) under Different pH Conditions

作　　者：叶丽君[1] 邵伟琪[1] 王兴莉[1] 黄雪松[1] 

机构地区：[1]暨南大学食品科学与工程系,广东广州510632

出　　处：《食品科学》2012年第19期35-38,共4页Food Science

基　　金："十二五"国家科技支撑计划项目(2012BAD031B03);农业部公益性行业(农业)科研专项(210303077)

摘　　要：以火龙果色素提取液的吸光度变化为指标,研究其在pH2.0～9.0条件下的降解规律。结果表明:在室温(28℃)、pH2.0～9.0时,火龙果色素的最大吸收波长分别为532、534、536、534、535、536、538、543nm。火龙果色素在特定pH值条件下的降解符合一级反应规律。降解速率常数(k)与pH值呈抛物线关系。pH4.0～6.0范围内,k较小,色素稳定性较好。The effect of pH 2.0-9.0 on the maximum absorption wavelength of pitaya pigment extract was analyzed. Meanwhile, we studied the degradation kinetics of the pigment extract. It was found that pitaya pigment extract showed maximum absorption at 532, 534, 536, 534, 535, 536, 538 nm and 543 nm, respectively under the conditions of 28℃ and pH 2.0-9.0. The degradation of the extract obeyed first-order reaction at specific pH levels. A parabolic relationship between rate constant （k） and pH was found. At pH levels between 4.0 and 6.0, smaller k values were obtained and the extract was stable.

关 键 词：火龙果 甜菜苷 降解 动力学 

分 类 号：TS201.2[轻工技术与工程—食品科学]