紫色甘薯茎叶色素的提取及稳定性的研究

The study of the extraction and stability of sweet potato leaf pigments

以紫色甘薯茎叶为原料,探讨紫色甘薯茎叶色素提取的最佳工艺条件,并对其稳定性进行分析研究,结果表明:用体积分数为95%乙醇80mL,在50℃恒温下浸取30h,提取效率较好。pH对色素的色泽影响明显,在酸性条件下色泽稳定,适宜低温储藏;光照加快色素分解,宜在黑暗处保藏;金属离子Ca2+、Mg2+、Zn2+、Cu2+、Na+对色素稳定性几乎没影响,Fe3+使色素的吸光度值明显减少,溶液的颜色逐渐变成深黄色,Sn4+使溶液的颜色逐渐加深,吸光度值变大;因此在甘薯茎叶的加工和使用过程中要避免与Sn4+、Fe3+接触。蔗糖、山梨酸钾和维生素C对色素的稳定性影响较小。

The paper explores purple sweet potato pigment extraction.Optimum conditions and stability were studied.The best extracting conditions were：95% ethanol at 50℃ for 30h.pH has a major influence：the pigment was more stable under acidic conditions and very sensitive to the light.Ca^2＋、Mg^2＋、Zn^2＋、Cu^2＋、Na＋had no effect on the pigment stability while Fe^3＋and Sn^4＋caused the pigment color to change.