摘要
研究了真空浓缩法和常压浓缩法对砂梨浓缩汁中抗坏血酸 VC 和β-胡萝卜素 VA原 含量的影响 .结果表明 ,真空浓缩法对砂梨汁中 VC及 VA原 的保存有利 ,常压浓缩法中其损失较大 .在低温真空浓缩法中 ,随着真空度的提高 ,砂梨汁中 VC的保存率也逐步提高 ,当真空度超过 93.33 k Pa时 ,VC的保存率可达10 0 % ,VA原 的保存不需太高的真空度 .
The effects of two concentration methods on the content of ascorbic acid(V C) and β-carotenoid in the concentrated pearjuice are studied. The results show that the vacuum concentration method(-0.02 mPa,(75~78) ℃)benefits preserve L ascorbic acid and β-carotenoid.The atmospheric concentration method doesnot work very well.With the in crease of vacuum,the preservation proportion of V C in pear juice has been in creased correspondingly,when vacuum value is 93.33 kPa,its preservation proportion of V C can reach up to 100%,β-carotenoids preservation does not need too high vaccum value.
