不同高压均质条件对罗望子浊汁稳定性及抗氧化活性的影响

Effects of different high pressure homogenization conditions on stability and antioxidant activity of Tamarind turbid juice

为提高罗望子浊汁物理稳定性和抗氧化活性,该实验研究了均质压力、进料温度和均质次数对罗望子浊汁稳定性和抗氧化活性的影响。结果表明,一定范围内随均质压力(0~25 MPa)的增加、进料温度(30~50℃)的提高和均质次数(1~3次)的增加,浊汁的粒度减小,稳定性提高。过高的进料温度(60~70℃)和均质次数(4~5次)导致浊汁稳定性下降。浊汁多糖含量对均质条件的变化不敏感,适当的均质压力(0~15 MPa)可以提高浊汁中总酚、黄酮含量、DPPH自由基和羟自由基清除能力。进料温度升高和均质次数增加导致浊汁中总酚、黄酮含量和ABTS自由基清除能力相比对照组显著降低(P<0.05)。浊汁总酚和黄酮含量与3种自由基清除能力间呈现较好相关性。正交实验得到最优工艺条件为进料温度50℃、均质压力25 MPa、均质次数2次,此条件下,浊汁离心沉淀率为1.18%、上清液浊度为435.50NTU,显著优于对照组,可用于生产。

In order to improve the physical stability and antioxidant activity of tamarind turbid juice,the effects of homogenization pressure,feed temperature and number of homogenization on the stability and biological activity of Tamarind turbid juice were studied.The results showed that the particle size of the turbid juice decreases with the increase of the homogenization pressure(0-25 MPa),the increase of the feed temperature(30-50℃)and the increase of passes number(1-2 passes)within a specific range.Increased stability,Excessive feed temperatures(60-70℃)and passes number(4-5 passes)result in a decrease in the stability of the turdid juice.The content of polysaccharide in turbid juice is not sensitive to the change of homogenization conditions.The appropriate homogenization pressure(0-15 MPa)can increase the total phenolic,flavonoid content,DPPH free radical and·OH clearing ability in turbid juice.The increase in feed temperature and the increase in passes number resulted in a significant decrease in total phenolic,flavonoid and ABTS free radical scavenging activity in the turbid juice compared to the control group(P<0.05).There was a good correlation between the total phenolic and flavonoid content of turbid juice and the three free radical scavenging abilities.The optimum conditions were obtained by orthogonal experiments.The feed temperature was 50℃,the homogenization pressure was 25 MPa,and passes number was two passes.Under this condition,the centrifugal sedimentation rate of the turbid juice was 1.18%,and the supernatant turbidity was 435.50 NTU,which was remarkable.Better than the control group,it can be used for production.