IMPROVING MONOHYDRATE DEXTROSE ECONOMICS WITH ENZYMATIC RECONVERSION

The manufacture of pure dextrose crystals results in production of a q uantity of mother liquor (usually sold as a process co-product called hydrol) that contains the polysaccharides resulting from incomplete st arch hydrolysis. In sucrose exporting countries and in countries where sugar prices are not increased above the world market by tariffs, thi s co-product of monohydrate dextrose production does not command a ver y high price. Even in the United States where sugar prices are elevate d by tariff, hydrol sells at a lower price than other starch sugars. T his results in a significant negative impact on process economics. By separately reconverting the mother liquor portion of the recycle strea m (in a greens recycle dextrose monohydrate crystallization process) i t has been found possible to provide substantial increases in process yield and allow the nearly complete conversion of starch to monohydrat e dextrose, Utilizing reconversion, the process yield of a dextrose pl ant in Bangladesh was increased from 81% to 98%, resulting in a 91.5% reduction in the production of a low value co-product stream and a 13. 3% operating profit increase.