不同加工条件对橙汁Vc含量的影响

以新鲜橙子为原料,采用2,6-二氯靛酚滴定法,研究不同加工条件对橙汁Vc含量的影响。结果表明,去皮处理工序中,橙子暴露时间超过30 min时,Vc含量严重损失;不同的热烫工序下Vc含量有显著差异,热水热烫使Vc含量降低,而微波热烫Vc的损失率较热水热烫低,且Vc含量比鲜果增加了1.09%～1.34%;压榨打浆工序中,添加植酸且用研磨法打浆有利于保持Vc含量;灭菌工序中,橙汁在95℃下灭菌15 min,灭菌效果最好,且Vc的损失率最小。

The Influence of Processing Conditions of Orange Juice to Vitamin C Content

Using fresh oranges as material and the 2,6-dichlorindophenol titration method in vitamin C determination,the changes of vitamin C content at different processing conditions were studied in this paper.The results indicated that the content of vitamin C in orange juice was basically lost after exposuring in the air more than 30 minutes in the procedure of orange peeling.The contents of vitamin C were various during different blanching procedures.Hot water blanching reduced the content of vitamin C while the vitamin C loss rate of microwave blanching was lower than that of hot water blanching,and it increased 1.09%～1.34% than raw orange.During the pulping processing,addition of phytic acid and grinding method were beneficial for stabilizing vitamin C.The loss rate of vitamin C was the lowest and it had better effect of sterilization by pasteurization at 95 ℃ and 15 minutes.