黑莓汁的理化特性及贮藏期营养成分的变化

On the changes of physical and chemical properties and nutrient composition of blackberry juice in storage\

对黑莓浓缩汁的理化特性及其营养成分变化进行研究，结果表明：ｐＨ３～４，波长５１１～５１４ｎｍ时，果汁色泽最佳；果汁抗氧化还原能力很弱，但具有很强的光和热的稳定性。０～４℃低温贮藏１年后，６种维生素的损失率都超过５０％；含糖量损失４０７％；ＳＯＤ活性和氨基酸含量分别损失１０％和１２４％；

Based upon investigations on physical and chemical properties and the change of nutrients of concentrated blackberry juice in storage, it was indicated that the best juice color occured at pH 3～4 and the absorptive wavelength of 511～514 nm. In spite of its low activity in anti oxidation and anti reduction, it appears high stability both to light and heat. After one year storage under low temperature (0～4℃), the losses of 6 kinds of vitamin, sugar, SOD activity and total amino acids are >50%, 40.7%, 10% and 12.4% respectively, whereas the acid content of the juice is a little bit increased.