桑椹色素提取方法及特性的初步研究

桑椹中的色素是一类天然的且具有潜在商业价值的着色素。研究了桑椹色素的提取方法及对光照、温度、氧化剂和还原剂等的稳定性。桑椹色素的最佳提取工艺条件:提取剂95%乙醇与0.1%HCl的体积比为1∶1;温度70℃;提取时间2h。桑椹色素的最大吸收波长为516nm,对光照、氧化剂、还原剂不稳定,3周光照处理后,色素损失率达19.55%;80℃下保存3h,色素损失率达20.9%,但在低温下相对稳定;吸收值随着过氧化氢或亚硫酸钠浓度的增加而减少,但色素的损失率随着浓度的增加而增加;吸收值随时间的延长而降低。

Preliminary Study on Extraction and Characteristics of Mulberry Pigment

Mulberry tree has been widely cultivated for its leaves and fruits. In fruits, pigment is a kind of natural colorant and has potential commercial value. This study focuses on extraction of mulberry pigment and the stability towards sunlight, temperature, oxidant and reductant. weight to volume of extraction solvent. The results showed as follows: The optimum conditions of extraction were found to be the extraction solvent extraction time of 2 h. The maximum absorption wavelength of extracts was 516 nm. The solution of mulberry pigment was unstable to sunlight, oxidant and reductant. After exposure to light for 3 weeks, the rate of colour loss of pigment reached 19.55%. When the pigment was kept at 80 ℃ for 3 h, the loss rate reached 20.90%. But it was stable at low temperature relatively. The absorbance decreased with increase of hydrogen peroxide or sodium sulfite concentrations and the colour loss of pigment increased. And the absorbance decreased correspondingly with time.