紫甘薯色素的提取及稳定性研究.pdf

154 2011, Vol. 32, No. 18 食品科学 ※工艺技术 紫甘薯色素的提取及稳定性研究 陈 杰，李进伟，张连富 (江南大学食品学院，江苏无锡 2 14 122) 摘 要：研究紫甘薯天然色素的提取及稳定性。利用响应面试验设计得出色素提取的最优条件是提取温度60 ℃、 提取时间1h 、料液比1:30 、水溶液中酸化乙醇( 乙醇:盐酸＝85 : 15 ) 体积分数80 % ，紫甘薯色素提取率理论值为 12.4688mg/g ，最优条件验证实验紫甘薯色素得率为12.3528mg/g 。随着温度的升高和加热时间的延长，紫甘薯色素 稳定性也下降；紫甘薯色素在中性和碱性条件下稳定性较差，因此在提取、贮藏、应用中宜采用酸性条件。F e3+ 、 A l3+ 两种金属离子对色素起保护作用，而Cu 2 + 、Z n 2 + 、Pb 2 + 三种金属离子对色素起破坏作用；抗坏血酸能够显著 的增加色素溶液的稳定性，而N a2 SO 3 会降低色素溶液的稳定性。 关键词：紫甘薯色素；响应面；提取；稳定性 Extraction and Stability of Purple Sweet Potato Pigment CHEN Jie ，LI Jin -wei ，ZHANG Lian-fu (School of Food Science and Technology, Jiangnan University, Wuxi 2 14 122, China) Abstract ：Purple sweet potato pigment (PSPP) is a kind of natural pigment and has gained extensive concern in recent years. In this study , respon se surface methodology was employed to optimize the extraction condition s of PSPP. The results showed that the optimal extraction conditions were extraction temperature of 60 ℃, extraction time of 1 h, solid-to-liquid ratio 1:30, and acidic ethanol concentration of 80%. Under the optimal extraction conditions, the yield of PSPP was up to 12 .4688 mg/g. In addition, the stability of PSPP was also investigated. Increasing temperature and extension of heating time could result in a decrease in PSPP stability. Similarly, the stability of PSPP revealed an obvious decrease in neutral and alkaline environments. Fe3+ and Al3+ could increase the stability of PSPP; on the other hand, Cu2+ , Zn2+ and Pb2+ could lead to a decrease in PSPP stability. Moreover, ascorbic acid could significantly improve the stability of PSPP and Na2 SO3 did harm to the st