摘要
研究了浓缩橙汁中的碳水化合物组成以及它们对产品的玻璃化转变温度和粘度的影响 .由压榨工艺和酶法工艺制备的浓缩橙汁在含量较少的大分子碳水化合物的组成上存在明显差异 ,而在含量占优势的低分子量化合物的组成上却很相似 .两种橙汁的玻璃化转变温度相近 ,但酶法工艺所制得橙汁的粘度明显高于前者 .添加平均相对分子质量为 3 60 0的麦芽糊精M0 4 0能提高浓缩橙汁的玻璃化转变温度 ,但幅度不大 ,而产品的粘度却能显著上升 .
The composition of carbohydrates in concentrated orange juices(COJ) and its effects on glass transition temperature and viscosity of the products were investigated. Concentrated orange juices obtained by two different treatments were different in the constituents of high molecular weight (Mw) carbohydrates, which were the minorities of the total solids of COJ. However, they resembled in the constituents of low Mw compounds, which were overwhelming majorities of the total solids of COJ. This made that the two kinds of juices were similar in glass transition temperature, but viscosity of COJ produced by enzymatic process was higher than that of COJ produced by squeezing. Maltodextrin M040 with an average molecular weight of 3600 was added to increase the glass transition temperature of COJ, but the increasing extent was not significant, however, the viscosity of COJ increased obviously.
关键词
浓缩橙汁
碳水化合物
玻璃化转变
粘度
concentrated orange juice
carbohydrates
glass transition
viscosity
