影响杨梅鲜汁中红色素稳定性的因子研究

Study on the stability of red pigment from waxberry

研究了pH值、温度、光照、金属离子和添加剂等对杨梅鲜汁中红色素稳定性的影响,结果表明:杨梅果汁中的红色素对酸碱度极其敏感,热稳定性差,耐氧化(过氧化氢)和还原(亚硫酸钠)性极差,防腐剂(苯甲酸钠)的消色作用较大。柠檬酸使果汁的色泽更加艳丽,NaCl和Vc也有不同程度的增色效果;蔗糖对色素的影响不大。6种可能接触的金属离子中,该色素对Fe2+、Cu2+最敏感,虽然其吸光度有所增加,但果汁色泽暗淡;Na+、 K+、Zn2+、Ca2+对该色素的影响较小。室内自然光和紫外光有一定的消色作用,室内暗藏较适宜。

The effects of pH value, temperature, light, metal ions and additives on the stability of red pigments from waxberry were studied. The results Showed that the pigments were very sensible to acidity and alkalinity, and had a poor thermal stability, and oxidants （hydrogen peroxide）, reductants （sulfite sodium） and the preservative （sodium benzoate） obviously degraded the tone of pigment. Citric acid, sodium chloride and vitamin C had influences on improving the pigments and sucrose had little influence on the pigment stability. The existence of Fe^2＋ and Cu^2＋ could increase the absorbance of the juice and make the color of juice darker,and K^＋, Ca^2＋,Na^＋and Zn^2＋ had little effects on the pigments. Exposure to indoor natural radiation and ultraviolet degraded the tone of pigments and dark room storage was good for the iuice stability.