甘薯紫色素的提取、纯化及稳定性研究  

Extraction, purification and stability of pigment from purple sweet potato

作　　者：钟希琼[1] 熊秋洁 邓定波 江玉敏 

机构地区：[1]佛山科学技术学院食品与园艺学院,广东佛山528231

出　　处：《广东农业科学》2014年第19期99-102,共4页Guangdong Agricultural Sciences

摘　　要：以体积分数为1%盐酸溶液作为提取剂,紫甘薯根块与提取剂比例为1 g∶2 mL,4℃提取24 h,抽滤后得到色素粗提液;用AB-8大孔树脂吸附,pH 2.6柠檬酸-磷酸氢二钠缓冲液除杂,70%乙醇溶液洗脱,得到色素纯化液。分析不同pH条件下与常用食品添加剂共存时紫色素的稳定性。结果表明,在pH 1-10的范围内,甘薯紫色素的色泽变化为红色→淡红→紫红。防腐剂、抗氧化剂、氧化剂对甘薯紫色素有不同程度的破坏作用,甘薯紫色素对防腐剂丙酸钠、抗氧化剂D-异抗坏血酸钠和氧化剂H2O2较敏感,稳定性较差,使用时应尽量避免与这几种物质共存;对还原剂Na2SO3不太敏感,稳定性较好。而蔗糖、咸味物质NaCl、柠檬酸和磷酸对甘薯紫色素有不同程度的增色作用。An optimal extraction condition for pigment from purple sweet potato was obtained as following： the material with a 2-fold（g/mL） volume of 1% hydrochloric acid（V/V） for 24 hours at 4℃. The optimal condition of purification for pigment was obtained, AB-8 resin was used to purify the crude pigment extract, pH 2.6 citric acid-disodium hydrogen phosphate buffer was used to remove impurities, and the elution solvent was 70% ethyl alcohol. The stability of the pigment from purple sweet potato under different conditions including pH and common food additives were analyzed. Result showed that the pigment color was from red to reddish, then to purple, when pH value was from 1 to 10. Preservatives, antioxidants and oxidant could decompose it, especially sodium propionate, sodium erythorbic acid and hydrogen peroxide. So we should avoid pigment from purple sweet potato coexisting with these kinds of materials; but sweetener and salt, especially acid could protect or improve the color.

关 键 词：紫甘薯 紫色素 提取 纯化 稳定性 

分 类 号：S531[农业科学—作物学]