Converted starches

Approximately 95% of the malt produced is used to make beet while small amounts are used as distillers and food malts. Distillers malt, which is used to convert starch-containing grains into fermentable sugars, is prepared almost exclusively for its enzymes, especially a-amylase (see Beverage SPIRITS, distilled). Food malts are sold for their davor and/or enzyme contribution to food products. 

Several alkenes occur naturally in living organisms. Some of these alkenes act as hormones and control biological functions. Plants produce ethene as a hormone to stimulate flower and seed production and to ripen fruits. Ethene stimulates enzymes in the plants to convert starch and acids of unripe fruit into sugars. The enzymes also soften fruit by breaking down pectin in cell walls. 

Converted starches, 4 720 Converter passes, in sulfur burning, 23 774-776... 

Prior to 1939, however, it was not known whether the cyclodextrins were products of the synthetic metabolism of Bacillus macerans, and therefore, perhaps, quite different from the components of starch, or whether they were formed by a single enzyme and therefore closely related to the starch structure. Then, Tilden and Hudson announced the discovery of a cell-free enzyme preparation from cultures of Bacillus macerans which had the ability to convert starch into the Schardinger dextrins without the production of maltose, glucose, or any other reducing sugars. They thus concluded that the Schardinger dextrins were either the true components of starch or closely related to such true components. 

These are accomplished in large fermenters in chemical plants, mostly in the Midwest. The cheapest feedstock is starch rather than sugar (other enzymes convert starch to glucose), and com from the Midwest is the cheapest source of starch. 

Spallanzani in 1783 (Sumner and Somers, 1953), the enzymatic hydrolysis of taimin was described by Scheele in 1786 (Tauber, 1949), in 1814 Kirchhoff observed that a glutinous component of wheat is capable of converting starch to sugar and dextrin, and Vogel showed in 1817 that an iirfusion of oats would produce a fermentable sugar from milk (Roberts et a/., 1995). 

HFCS processes could not have been developed if efficient enzyme-based production methods for converting starch into glucose had not already been developed. 

Wurzburg, O. B. (1986a). Converted starches. In O. B. Wurzburg (Ed.), Modified Starches Properties and uses (pp. 17 1). CRC Press, Florida. 

It was a good idea, but it didn t work. No microbe that Weizmann tried yielded isoprene. But Clostridium aceto-butylium did convert starch into a mixture of ethanol, acetone, and butanol, a blend that did not particularly interest Weizmann. It certainly interested Lloyd George, however he heard the whole account from Weizmann himself. Here, pehaps, was a way to produce the acetone that they sorely needed for the manufacture of cordite. Weizmann was asked to scale up his experimental process, and within a short time he d converted a gin distillery into a factory to make his mixture. He easily separated the acetone through distillation, and soon mass production was under way. There was no need for butanol, and huge stocks built up. But after the war the... 

Industrial process for converting starch into dextrose (glucose) are described under Starch. 

The role served by mall in the later production of beer and distilled spirits is that of furnishing enzymes, which convert starches and other... 

Prinz IF, deWijk RA. Sensory correlation of glucose levels in a starch-based semi-solid model system before and after alpha-amylase breakdown. Archives of Oral Biology 2007, 52,168-172. Note that the amylase content of saliva from the mouth readily converts starch to glucose. 

Converted starches, also called thin-boiling starches, are produced by degradation of the starch chains into small segments. They can be cooked in water at higher concentrations than native starches. Low-viscosity starches are needed in applications where a high solid starch paste with a pumpable and workable viscosity is required. There are four classes of commercial converted starches dextrins (hydrolysis in solid-state) acid-modified starches (hydrolysis in a slurry) oxidized starches and enzymically depolymerized starches. 

Enzymes such as a-amylase and (3-amylase can break the starch chains into maltodextrins and starch sugars such as glucose and maltose. The heat-stable enzymes convert the starch after dissolving the starch by jet-cooking. Enzymatically converted starches are used in the food industry (confectionery, baking products, sweeteners), paper industry (surface sizing) and the fermentation industry. 

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