用碱性醋酸铅作澄清剂对废蜜的糖度和纯度测定的影响

Effect of Lead Subacetate as Clarificant on Determination of Pol and Purity in Final Molasses

在测定废蜜糖度时,由于杂质多、颜色深,因此要加入较大量的碱性醋酸铅干粉澄清才能得到清晰透明的滤液,但用量过多,则会使糖蜜、视纯度的测定结果升高。这主要是由于碱性醋酸铅能吸附除去糖液中部分果糖,致使左旋光度降低右旋光度升高的结果。认为,以碱性醋酸铅作澄清剂,其加入量应以滤液能清楚观测旋光度为宜。

Large amount of lead subacetate powder must be added into final molasses to obtain clear filtrate during determination of Pol in final molasses, which contains much impurity and the colour is dark. While too much amount of lead subacetate may lead to an erroneous high indication of Pol and A. P., Since lead subacetate can absorb and remove part of levulose, resulting in a decrease levorotation and a rise dextrorotation. It is considered that lead subacetate should be added properly till polarization of the filrate can just be observed clearly.