| 摘要 |
Production of crystalline glucose comprises preparing a low-dextrose starch conversion liquor from starch and water in the presence of alpha amylase or strong mineral acid, further hydrolysing with amyloglucosidase until the glucose content of the solids of the liquor is not less than 83%, concentrating the further hydrolysed liquor to a % dry substance which varies inversely with the glucose of the solids of the liquor according to the table .% glucose of the solids.% dry substance .82.0-85.9.60-87.2 .86.0-89.9.59-86.2 .90.0-92.9.58-85.2 .93.0-94.9.57-84.2 .95.0-95.9.56-83.2, adjusting the temperature of the concentrated liquor to a crysallization temperature in the range 20-54 DEG C., seeding the liquor with crystals of glucose, controlling the glucose supersaturation, i.e. the ratio of observed glucose concentration to the known equilibrium concentration of glucose in water at the same temperature, to 1.02-1.20 by regulation of the liquor temperature, and separating the mother liquor from the crystalline glucose formed. The starch may be from maize, milo (sorghum), wheat, potato, rice or tapioca. Sources of the amylo-glucosidase are culture broths of the moulds Rhizopus delemar, selected strains of Aspergillus niger, A. phoenicis and A. oryzae. The production is preferably conducted continuously, starch paste thinned by the alpha amylase or acid being mixed with the separated mother liquor after it has been treated with ion-exchange resins to remove enzymes and reduce its mineral content sufficiently to maintain the ash/total solids of the syrup fed to the glucose crystallizing step at less than 3%, and the mixture being treated, after saccharification by the amyloglucosidase, with an absorbent to remove colour bodies and other soluble impurities. U.S.A. Specifications 2,531,999, 2,557,078, 2,567,000, 2,717,582, 2,881,115 and 2,893,921 are referred to.
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