膜法红糖制备过程糖汁营养物质变化及其对红糖结晶的影响

Changes of Nutrients in Sugar Juice During Preparation of Brown Sugar by Membrane Method and Their Effects on Crystallization of Brown Sugar

以不同温度混合汁为原料,采用50 nm陶瓷膜过滤后获得的清汁制备红糖,研究膜法红糖制备过程关键工序营养物质(糖分、蛋白质、氨基酸及有机酸)的变化规律及原因,并探究了糖浆质量对蔗糖结晶的影响。结果表明,在生产过程中,糖汁的pH值下降量为1.63~1.97,氨基酸消耗率达55.4%~61.52%;蔗糖和蛋白质含量呈先增加后减少的趋势,有机酸、还原糖、果糖、葡萄糖对锤度的比值不断增加,说明在膜法红糖生产过程中发生了蔗糖转化、还原糖碱性分解、蛋白质分解及美拉德等反应。当糖浆pH值低于3.98、纯度≤79.06%、还原糖含量≥8.50%时,糖浆中蔗糖则无法自然结晶析出形成红糖产品。该研究结果为膜法红糖的实际生产提供了一定的参考依据。

In this paper,brown sugar is prepared from clear juice filtered by 50 nm ceramic membrane with mixed juice at different temperatures as the raw material,the change rule and causes of nutrients(sugar,protein,amino acid and organic acid)of key process during the preparation of brown sugar by membrane method are studied,and the effect of syrup quality on sucrose crystallization is explored.The results show that the pH value of sugar juice decreases by 1.63~1.97 and the amino acid consumption rate reaches 55.4%~61.52%during the production.The content of sucrose and protein increases firstly and then decreases,and the ratio of organic acid,reduced sugar,fructose and glucose to Brix increases continuously,indicating that sucrose transformation,alkaline decomposition of reducing sugar,protein decomposition and Maillard reactions occurr in the production process of brown sugar by membrane method.When pH value of syrup is lower than 3.98,purity is≤79.06%and reducing sugar content is≥8.50%,sucrose in syrup cannot naturally crystallize and seperate out to form brown sugar products.The research results have provided some references for the actural production of brown sugar by membrane method.