摘要
以莴笋叶为原料,采用水浴法提取色素,考察了p H、光照、温度、氧化剂和还原剂对莴笋叶色素稳定性的影响,对不同温度下莴笋叶色素的热降解动力学进行了分析。结果表明,光、热、氧化剂、还原剂对莴笋叶色素稳定性均具有重要影响。莴笋叶色素在光的照射下会发生降解,但降解速率略有不同,其降解速率依次为紫外光>日光灯>暗处,应避免紫外光直接照射。莴笋叶色素在氧化剂的作用下会发生降解,还原剂具有一定的增色作用,在保存或加工过程中应避免氧化剂,可添加一定量的还原剂以保护色素。莴笋叶色素具有一定的耐热性,但随着温度的升高会发生降解,色素热降解符合动力学一级反应,室温25℃下莴笋叶色素降解的速率常数为k=1.54×10-2,t1/2=45 h。该色素在中性至碱性条件下性质稳定,可用作中性饮料等食品的着色剂。该研究可为莴笋叶色素的综合利用和莴笋叶的深加工提供一定的理论依据。
With lettuce leaves as the raw material, the effect of pH, light, heat on the stability of lettuce leaves pigment was investigated. The quantitative analysis of pigment heat degradation in different temperature was studied. The results are as follows ： the light, heat, oxidant and reductant had an important influence on the stability of lettuce leaf pigments. Lettuce leaf pigments are degraded under light, but the degradation rate was different and in an order of Ultraviolet light 〉 fluorescent lamp 〉 dark. Therefore ultraviolet irradiation should be avoided. Lettuce leaf pigment degradation happened under oxidation, but reductants enhanced pigment. The oxidant should be avoided or reducing agent should be added ruing the storage time. Lettuce leaf pigment had certain heat resistance, but with temperature increase, degradation happened. The heat degradation of lettuce leaves pigment was a first-order reaction and k =1.54 × 10-2, t1/2=45 h. The pigment showed stable in neutral and alkaline conditions, therefore, it can be used as a neutral beverage as food colorants. The study provides theoretical basis for comprehensive utilization of lettuce leaf pigments and further processing of lettuce leaves.
作者
张娜
魏龙
蒋彩飞
吕腾飞
ZHANG Na WEI Long JIANG Cai-fei LV Teng-fei(Department of Food Science, Zhengzhou Institute of Science and Technology, Zhengzhou 45006)
出处
《中国食品添加剂》
CAS
北大核心
2016年第12期94-98,共5页
China Food Additives
基金
郑州市科技局科技攻关项目(20150420)
关键词
莴笋叶色素
热降解
动力学研究
稳定性
lettuce leaves pigment
heat stability
kinetics
stability
