PURPOSE: To readily and industrially obtain a starch saccharide useful as low- viscosity saccharides with low sweetness at a low cost without microbial contamination, by reacting starch and/or partial hydrolyzate thereof with a specific α-amylase.
CONSTITUTION: A microorganism, such as FERM P-8881, of the genus Thermus capable of producing α-amylase and pullulanase is cultivated to afford the aimed α-amylase having the following physicochemical properties. Action; specifically hydrolyzing straightchainlike structure of α-1,4-glucopyranoside bonds in starch, etc., and partial hydrolyzates thereof to form maltose, etc., as a principal component and α-type ionomer of the product. Substrate specificity; hydrolyzing straight-chainlike maltooligosacharide of α-1,4-glucopyranoside bonds having a higher polymerization degree than that of maltotetraose, etc. Optimum pH; 5.5W6. Action temperature; about 70°C. Inhibition; Hg++, etc. Activation; Ca. Molecular weight; 135000±5000. Isoelectric point; 4.1±0.1, etc. The resultant amylase in an amount of 0.3W2 units/g starch is then added to a 2W40wt.% solution of starch, etc., and reacted at 60W80°C to afford the aimed starch saccharide.
HORIKOSHI KOKI
NAKAMURA NOBUYUKI
HORIKOSHI KOKI