Uncooked starch

Starch processing is a fairly mature technology, but recent advances in starch processing have improved the economics and efficiency of the process. For example, a simpler low-pH a-amylases process has been developed, improving the ethanol yield and reducing costs [20], The other major advance is the development of enzymes that function on raw, uncooked starch, thereby improving overall process economics [21, 22],... 

Uncooked starch suspensions can easily spoil. If suspensions are to be held for more than a few hours, a preservative (biocide) needs to be added. Some commonly used reagents, such as chlorine or sodium hypochlorite, will attack (oxidize) starch. This reaction has to be considered when choosing a preservative. 

Uncooked starch slurries are sometimes added at the wet-end, intending that the starch cooks in the dryer section. This procedure is satisfactory only if the temperature of the web is high enough to gelatinise the starch granules in situ, otherwise no value is derived from the uncooked starch granules they merely act as filler and lower the strength of the paper [3]. 

Uncooked starch is occasionally sprayed between the plies on multi-ply paper and board mills as the simplest solution to the problem of poor or variable inter-ply bonding. 

Mori and Inaba (1990) applied a PV technique to attain both high productivity and efficient recovery of EtOH from a fermentation broth. The manbrane bioreactor consisted of a jar fermenter and a PV systan for the direct production of EtOH from uncooked starch with a thermophilic anaerobic bacterium, Clostridium thermohydrosulfuricum. From the four types of EtOH-selective monbranes tested, microporous PTFE membrane, the pores of which were impregnated with silicone rubber, was chosen for its large flux, high EtOH selectivity, and high stability. During... 

Starches from different plant sources differ substantially in histologic features and in the chemical heterogeneity of the granule components. Relatively scant information is recorded on the utilization of starches as food for man and animals. Such information has shown that uncooked starches from the cereal grains are well utilized and that from raw potatoes, in contrast to the starch in cooked potatoes, is poorly utilized by human subjects 4). 

Utilization of Raw (Uncooked) Starches at a Level of 63.7% in Diets Fed AD Libitum to Young Rats for Periods of 28 Days (5)... 

Uncooked starch is resistant to amylase action, because it is present as small insoluble granules. The process of cooking swells the starch granules, resulting in a gel on which amylase can act. However, as cooked starch cools, a proportion undergoes crystallization to a form that is again resistant to amylase action — this is part of the process of staling of starchy foods. 

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