紫甘薯天然色素的微波提取及性质研究.pdfVIP

紫甘薯天然色素紫甘薯天然色素的微波提取及性质研究的微波提取及性质研究 紫甘薯天然色素紫甘薯天然色素的微波提取及性质研究的微波提取及性质研究 摘要：紫甘薯中含有丰富的花色苷类物质，是一种极具开发价值的天然色素资源。本文 对紫甘薯天然色素的微波辅助提取条件及性质进行初步研究。结果表明，用微波辅助提 取紫甘薯天然色素，不仅节省时间，而且提取效果好。通过单因素和正交试验得出微波 提取紫甘薯天然色素的最佳条件是：微波功率 60% （480 W ），提取时间 60 s、料液比 （g ： ml ）1：3，提取次数为 3 次。紫甘薯天然色素的浓度与其 OD 值之间有很强的正相关性； pH 值对色素最大吸收峰有明显影响，pH3.0 以下色素最大吸收波长为520 nm ；色素在酸 性条件下较稳定，随着 pH 值升高，稳定性逐渐下降，强碱性条件下易被破坏；光的直 2+ 2+ + 2+ 2+ 3+ 接照射会影响色素的稳定性；金属离子 Cu 、Ca 、K 、Mg 、Fe 和 Fe 对色素的影 响不明显；同时，糖、盐和防腐剂对色素的影响也较小，但 H O 对紫甘薯天然色素影响 2 2 较大。 关键词：紫甘薯；天然色素；微波辅助提取；性质 Microwave Assisted Extraction and Properties of Natural Pigment from Purple Sweet Potato Abstract ：：The microwave assisted extraction conditions and some physical and chemical ：： properties of the natural pigment from the purple sweet potato were preliminarily investigated. The results showed that the microwave assisted extraction was effective method in this study. Based on a series of single factor and their orthogonal experiments, it was found that the best conditions of extraction for natural red pigment from purple sweet potato were ：microwave power 480 W, extraction time 60 s and the ratio of solid to liquid 1：3 （g ：ml ）. The pigment was significantly affected by the pH value, and it was very stable under acidic conditions, when the peak of absorption wavelength was at 520 nm. Additionally, sugar （5% sucrose and 5% glucose ）, salt （1% NaCl） and antiseptic （1% Sodium benzoate）, and some metal ions 2+ 2+ 2+ + 3+ 2+ such as Cu , Ca , Fe , K , Fe and Mg had little effect on its stability. However, H 0 had