龙葵果花色苷降解动力学

Degradation Kinetics of Anthocyanins from Solanum nigrum L. Berries

通过研究4种龙葵果花色苷提取物在不同pH值和温度下的降解动力学过程,得出其降解规律。结果显示,龙葵果花色苷的降解符合一级反应动力学模型。相同pH下随着温度的升高,龙葵果花色苷的降解速率常数呈现指数型增长趋势,半衰期呈现指数型下降趋势。60℃和70℃时随着pH的增大,粗提物、一级精制物的降解速率常数呈现对数型增长趋势,而组分1和组分2的降解速率常数则呈现指数型增长趋势,4种提取物的半衰期均呈现指数型下降的趋势。而80℃和90℃时,4种花色苷提取物的降解速率常数和半衰期并未呈现规律性的变化。4种龙葵果花色苷提取物均在60℃、pH 1.0时降解最慢,稳定性最好,其中粗提物的稳定性最强。

The degradation kinetics of 4 anthocyanins extracts from Solanum nigrum L.berries under different pH and temperature was investigated.The results as follows：the degradation of anthocyanins from Solanum nigrum L.berries follows the first-order reaction kinetics.The reaction rate constant of the anthocyanins degrading reaction was increased in exponential pattern as the temperature went up and the half-life was reduced in exponential pattern.60 ℃ and 70 ℃,the reaction rate constant of crud and purified extracts degrading reaction were increased in logarithmic pattern as the pH went up and the half-life was reduced in exponential pattern.The reaction rate constant of fraction 1 and fraction 2 degrading reaction were increased in as the exponential pattern pH went up and the half-life was reduced in exponential pattern.However,80 ℃ and 90 ℃,the rate constants and half-life were not changed regularly.4 kinds of anthocyanins extracts were stability relatively under 60 ℃ pH 1.0,and crud extracts was more stable than the other three.These results indicated that the anthocyanins suited to cold-process for food coloring.