萱草花色素的超声波辅助提取及其稳定性研究

以‘摩盒’萱草花为试验材料,对萱草花色素的超声波辅助提取工艺进行了优化,同时研究了光照、温度、pH值、氧化剂、还原剂对萱草花色素提取液稳定性的影响。结果表明,用纯乙醇做提取液,料液比为1∶10、超声时间30 min时,提取效果最好;萱草花色素对光照比较敏感,在暗处稳定性最高,在自然光下次之,直射光下最低;萱草花色素在35℃以下热稳定性较好,超过35℃时热稳定性大大降低;花色苷类在强酸时稳定,弱酸性和中性条件下稳定性降低;类胡萝卜素类在酸性条件下不稳定,在中性和弱碱性条件下保持稳定;花色苷类和类胡萝卜素类抗氧化能力较好,抗还原能力差。

Research on Stability of Pigment from the Flowers of Hemerocallis with Ultrasonic-assisted Extraction

Extraction of pigment from the flowers of Hemerocallis fulva cv.Pandora's Box,and the effects of some influential factors including temperature,pH,light,oxidant and reductant on the stability of the pigment were also experimented in this paper.The results showed that the best extraction conditions were found as follows: 100% ethanolas extraction solvent at a solid-to-liquid ratio of 1∶10(g/mL) with the assistance of 30 min ultrasonic treatment.The stability of the pigment was highest in the hidden place,next under the natural light,and the lowest under sunlight.The thermo stability of the pigment was good below 35 ℃,but it decreases above 35 ℃.The anthocyanin was stable to strongly acidic environments while unstable to slightly acidic or nearly neutral environments,and the carotenoid was stable to slightly alkali and nearly neutral environments while unstable to acidic environments.The pigments also had a good resistance to oxidant and a poor resistance to reductant.