金桂与丹桂醇溶性色素的提取及其稳定性比较

用不同体积分数的乙醇从金桂和丹桂的花瓣中浸提所含的花色苷类色素,用光谱扫描法检测该色素的光吸收特性,比较不同乙醇体积分数、不同浸提时间对色素浸提效果的影响,并进行光敏感性试验和酸碱影响试验。结果显示,金桂和丹桂的花色素用体积分数90%的乙醇浸提具较高的浸出率;延长浸提时间可提高色素浸出率;紫外线直射可使色素的色度大幅度下降,日光灯和散射光也会导致色度在一定程度上的下降;色素在酸性溶液中具一定的稳定性,但在碱性溶液中表现出不稳定性。

Extraction and Stability of Ethanol - Solvent Pigments from Osmamthus fragrans var. thunbergii and Osmamthus fragrans var. aurantiacus

The anthocyanin pigment was extracted from the petals of Osmamthus fragrans var.thunbergii and Osmamthus fragrans var.aurantiacus by different concentrations of ethanol.Its property of light absorption was measured by spectrophotometry to compare the effects of different concentrations of ethanol and different extraction time on the pigment extraction.The light sensitivity and acid-base effect experiments were also done.The results showed that extraction rate of the pigment from Osmamthus fragrans var.thunbergii and Osmamthus fragrans var.aurantiacus was higher by using 90% ethanol and could be increased by prolonging extraction time.The chroma of the pigment was greatly reduced by ultraviolet radiation and was lessen in some degrees by fluorescent and scattered light.The pigment was stable in acid solution but was unstable in base solution.