Dehydrated starch

Fig. 30.—The course of starch dehydration (in dgldt, where g is weight and t is time) for potato (P), wheat (W), and rice (R) starch. (From Schierbaum and Taeufel.- 47)...

Molisch s Test. Dissolve about 01 g. of the carbohydrate in z ml. of water (for starch use 2 ml. of starch solution ), add 2-3 drops of a 1 % alcoholic solution of i-naphthol (ignoring traces of the latter precipitated by the water) and then carefully pour 2 ml. of cone. H2SO4 down the side of the test-tube so that it forms a heavy layer at the bottom. A deep violet coloration is produced where the liquids meet. This coloration is due apparently to the formation of an unstable condensation product of i-naphthol with furfural (an aldehyde produced by the dehydration of the carbohydrate). 

The drill-in fluids are typically composed of either starch or cellulose polymers, xanthan polymer, and sized calcium carbonate or salt particulates. Insufficient degradation of the filter-cakes resulting from even these clean drill-in fluids can significantly impede the flow capacity at the wellbore wall. Partially dehydrated, gelled drilling fluid and filter-cake must be displaced from the wellbore annulus to achieve a successful primary cement job. 

For pertinent reviews on HMF, see (a) Lewkowski, J. Synthesis, chemistry and applications of 5-hydroxymethylfurfural and its derivatives, ARKIVOC, 2001, 17-54 (b) B. F. M. Kuster, Manufacture of 5-hydroxymethylfurfural, Starch/Starke, 1990, 42, 314-321. Newer developments (c) Bicker, M. Hirth, J. Vogel, H. Dehydration of fructose to 5-hydroxymethylfurfural in sub- and supercritical acetone. Green Chem.,... 

Glnco-amylase enzyme converts the starch into D-glucose. The enzymatic hydrolysis is then followed by fermentation, distillation and dehydration to yield anhydrous bioethanol. Com (60-70% starch) is the dominant feedstock in the starch-to-bioeth-anol industry worldwide. 

Some naturally occurring polymers such as cellulose, starch, wool, and silk are classified as condensation polymers, since one can postulate their synthesis from certain hypothetical reactants by the elimination of water. Thus cellulose can he thought of as the polyether formed by the dehydration of glucose. Carothers included such polymers by defining condensation polymers as those in which the formula of the repeating unit lacks certain atoms that are present in the monomer(s) from which it is formed or to which it may be degraded. In this... 

In countries where a strong environmental regulation for industrial wastewater exists, purification of waste streams from potato factories regarding both the fruit water and the pulp is required. Several attempts have been made to dehydrate the by-products and to utilize them for different purposes. Its high moisture content (80%) requires an expensive drying due to the problem of spoilage, if left untreated. The starch industry tries to sell as much pulp as possible as wet or partially dried cattle feed. However, the need for potato pulp by farmers is limited. Potato pulp is being used as cattle feed as well as a solid-state fermentation media for the production of different biomolecules. Conventional applications of potato pulp are listed in Table 16.2. 

Himalaya s Explosives (Portugal). KC103 60-80, starch, charcoal etc 10-25, oil 4-10, metallic dust or powder 2-10, metallic oxides, or dehydrated CuS04 2-5%... 

Ethanemercarbide (called Dianhydro-hexakis-[hydroxymercurij-athan, or Athanmercarbid, in Ger), H0.Hg.(0Hg2)C.C(Hg20).Hg0H mw 1293.69, OB to CO2 -8.735, yel powd, detonates at 2"30°C (183° C). It may be prepd by heating EtOH, PrOH, allyl-OH, amyl-OH, AcH, cane sugar, starch, or cellulose w yel HgO in alk soln insensitive to impact, but crackles under friction. It dehydrates at 200—230°C prior to violent detn at 230°C not decompd by strong acid or alkali (Ref 2b)... 

Isosorbide and isomannide are important by-products of the starch industry, arising from dehydration of D-sorbitol and D-mannitol. These commercial starting materials provide an easy and inexpensive access to optically pure functionalized tetrahydrofurans like 04,05-isopropylidene-1-iodo-3,6-anhydro-1-deoxy-D-glucitol and 04,05-isopropylidene-l-iodo-3,6-anhydro-1-deoxy-Q-mannitol. This procedure describes a preparation of the former compound and the epoxide derived therefrom. 

Trehalose is a relatively new bulk sweetener with potential for use in soft drinks. It is a di-glucose sugar and it occurs in nature in shellfish and mushrooms, where it confers a degree of protection to plant and animal cells in conditions causing dehydration. This led to its use as a cryoprotectant in freeze-drying systems in the pharmaceutical industry. In food markets, its potential use is as a bulk sweetener. It is manufactured using the Hayashibara patented process using starch as a raw material. The process involves enzymatic conversion and crystallisation to the trehalose dehydrate crystal (LFRA, 2001). 

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