Maltose, general from starch

General protease, a-amylase, and exoglucanase activities were estimated using hide powder-, amylose-, and celliilose-azure substrates, respectively, as described earlier (49). Here, standard curves were developed for the hydrolysis of each azure-linked substrate by standard enzymes of known activity. By this method, one cellulose-azure hydrolysis unit corresponds to one filter paper unit, one unit of hide powder-azure activity corresponds to the hydrolysis of 1.0 nmole of iV-benzoyl-L-tyrosine ethyl ester (BTEE) per min, and one amylose-azure unit of activity corresponds to the hydrolysis of 1.0 nmole of maltose from starch per 30 min. 

In America, the main source material of sugars and syrups from starch is corn starch. The starch is hydrolyzed to simpler chemical substances through the action of dilute acid—generally hydrochloric acid—under heat and pressure in a converter. The products of hydrolysis products are dextrin, maltose, and dextrose. As the hydrolysis progresses, the content of dextrose increases at the expense of the others. The conditions of the conversion are regulated according to the amount of dextrose required in the product to be produced. 

Maltose A disaccharide comprising two molecules of glucose linked by an a-1,4-glycosidic bond. Maltose from starch or dextrins is generally produced via P-amylase. It occurs in high concentrations in germinated cereals or malt. 

Com symps [8029-43 ] (glucose symp, starch symp) are concentrated solutions of partially hydrolyzed starch containing dextrose, maltose, and higher molecular weight saccharides. In the United States, com symps are produced from com starch by acid and enzyme processes. Other starch sources such as wheat, rice, potato, and tapioca are used elsewhere depending on avadabiHty. Symps are generally sold in the form of viscous Hquid products and vary in physical properties, eg, viscosity, humectancy, hygroscopicity, sweetness, and fermentabiHty. 

Undecoxnpo ed starch may be detected microscopically and by its insolubility in water. There is generally a small amount of reducing material present from maltose, etc. It may be estimated by Fchling s solution. 

Starch.- —While many fermented liquors obtain sugar for conversion into alcohol from sources indicated above by far the largest single source of sugar, especially for distilled liquors, is the poly-saccharide, starch. Its importance arises from the fact that by suitable treatment almost 100% conversion of starch into fermentable sugars, dextrose, maltose, etc. can be obtained. Hence the general nature, occurrence and physical and chemical properties of starch are of major interest in the fermented liquor industry. 

Chemical Properties. From the food standpoint, probably the most important chemical property of the starch hydrolyzates is fermentability. Dextrose, of course, is well known to be readily fermentable by most organisms. Maltose, likewise, is generally readily fermentable. Thus the total of these two sugars roughly defines the fermentability of a hydrolyzate. Physical conditions permitting, the higher the dextrose equivalent, the higher the fermentability. 

---