黑加仑果汁中花色苷的贮藏稳定性

以黑加仑果汁为原料，研究不同温度、不同可溶性固形物含量和抗氧化剂（抗坏血酸）存在条件下贮藏过程中果汁花色苷的化学稳定性、降解动力学及颜色变化。结果表明：果汁中花色苷在4 ℃、可溶性固形物含量9°Brix条件下较稳定，随着贮藏温度升高和可溶性固形物含量升高，花色苷残留率越低。贮藏过程中花色苷的降解符合一级反应动力学，反应速率常数k越大，半衰期t1/2越小，活化能Ea越低。添加50 mg/L抗坏血酸使果汁花色苷降解速率常数k明显增大，半衰期t1/2和降解活化能Ea明显减小，因此抗坏血酸对花色苷残留率的减少有促进作用。在贮藏过程中随着时间的推移，花色苷不断的减少，果汁发生褐变，亮度和红色度逐渐降低，黄色度逐渐增加，而且抗坏血酸对贮藏过程中花色苷的颜色变化具有促进作用。

Storage Stability of Anthocyanins in Blackcurrant Juice

In this work, we examined the effects of storage temperature, soluble solid content (SSC) and added antioxidant
(ascorbic acid) on the chemical stability, degradation kinetics and color change of anthocyanins in blackcurrant juice. Results
showed that blackcurrant anthocyanins were stable at 4 ℃ and an SSC of 9°Brix. With an increase in storage temperature
and SSC, the level of residual anthocyanins was decreased. The degradation of anthocyanins during storage followed a firstorder
reaction. The higher the reaction rate constant k, the smaller the half-life t1/2, and the lower the activation energy Ea.
Addition of 50 mg/L ascorbic acid resulted in a significant increase in the degradation rate constant k of blackcurrant juice
anthocyanins and a significant reduction in the half-life t1/2 and the thermal degradation activation energy Ea. Therefore,
adding ascorbic acid had a positive on the reduction of residual anthocyanins. As the storage period progressed, the content
of anthocyanins in blackcurrant juice declined, and significant browning was observed in the juice together with a reduction
in brightness and redness and an increase in yellowness. In addition, ascorbic acid could promote the color change of
anthocyanins during storage.