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Sugarcane molasses is very abundant in sugar-refinery in Ssouth of China, which is one of the byproduct. The ratio of it to sugarcane is 2.5%～4.0%. Its composition is different because of the variety of the sugarcane,of breeding climate, of soil condition, of farm manage and of the technology of sugar refining. The main composition is sucrose, reducing sugar, colloid, ash, color matter. Sugarcane molasses contains 50%～60% sugar, most of which is fermentable. It is hard to pick-up the sugar from molasses unless some new method can be used. Otherwise, It is important and meaningful that produces more valuable products by fermentation, which can increases benefit of sugar-refinery.The molasses is a brown, extremely viscous liquid. The viscosity of molasses has relation to temperature, to the concentration and to colloid contained. The higher the temperature, the lower the viscosity and the more concentration, the higher the viscosity.Molasses components have 10% of the colloid, which has about 0.8% pectin, These colloidal substances can enhance the viscosity of molasses. In the industrialized applications, to remove these colloids, the main way is to add a polymer electrolyte like polyacrylamide. However, this approach would leads to substantive loss of sugar, to increase the mud weight and the burden on the environment, to decrease the economic value of molasses.In order to reduce the viscosity of molasses,I envisaged the use of high-performance alkaline pectinase specificity and mild reaction conditions to eliminate the pectin. The main results of research are as follows:Firstly gain the crude enzyme from Bacillus.gibsonii through solid-state fermentation and do a primary characterization analysis on it. The optimal pH is of 10.5 and optimal temperature of 55℃for activity. Between pH 9 and pH 10.5,the crude enzyme is stable. In the condition of no any stable substance added,it is stable at 55℃for a long time and quickly lost activity at 60℃. The effect of alkaline pectinase in molasses is researched. The results are as follws:In the condition of pH of 1G.5 and temperature of 55℃, alkaline pectinase could decreases 40% of the molasses viscosity. In the condition of pH of 10.5 and temperature of 55℃alkaline pectinase could reduce 7.5% of the color value of the molasses.The orthogonal optimization and analysis of range prove:the temperature is the uppermost factor, then is the pH, the lest is the amount of enzyme. The best array is the temperature of 35℃,the pH of 10.5,the amount of enzyme of 3 percent(V/V).This array can decreases over 50% of the molasses viscosity.
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