火龙果色素的提取工艺优化及色素稳定性研究

Study on extraction process optimization and stability of pitaya pigment

以不同品种火龙果果皮为材料,在单因素试验的基础上,采用L_9(3~4)正交试验法优化火龙果果皮色素的提取工艺,并对色素稳定性进行研究。结果表明,两种火龙果色素的提取条件及含量都有所差异,白肉品种火龙果果皮的最优提取条件为:浸取液40%乙醇、料液比1∶40(g/mL)、浸取时间25min、浸取温度40℃;红肉红皮品种则为:浸取液40%乙醇、料液比1∶30(g/mL)、浸取时间15min、浸取温度30℃。稳定性分析结果:高温不利于色素的稳定,Mg^(2+)、Fe^(2+)、蔗糖、VC和苯甲酸钠对色素稳定性影响不大,而Zn^(2+)、Cu^(2+)和H_2O_2对色素有强烈褪色作用,两种火龙果的色素稳定性差异不大。

The extraction process of pigment from the skin of different varieties of pitaya was optimized by using L9(3^4)orthogonal test method on the basis of single factor test. The stability of pigment was also studied. The results showed that the extraction conditions and contents of the two pitaya pigments were different. The optimal extraction conditions of the white pulp variety pitaya pigment were:extraction solution of 40% ethanol,solid-liquid ratio of 1∶40 g/mL,extraction time of 25 min and extraction temperature of 40℃;the optimal extraction conditions of red pulp variety pitaya pigment were:extraction solution of 40% ethanol,solid-liquid ratio of 1∶30 g/mL,extraction time of 15 min and extraction temperature of 30℃. Stability analysis results showed that the high temperature is not conducive to the stability of pigment,while Mg^2+,Fe^2+,sucrose,VC and sodium benzoate have little influence on the stability of pigment,Zn2,Cu2+ and H2O2 have strong depigmentation effect. There is little difference in pigment stability between the two pitaya species.