Starch phosphate, preparation

O Brien, S. Wang, Y.J. Vervaet, C. Remon, J.R Starch phosphates prepared by reactive extrusion as a sustained release agent. Carbohydr. Polym. 2009, 76 (4), 557-566. 

Starch monophosphates are quite useful in foods because of their superior freeze—thaw stabiUty. As thickeners in frozen gravy and frozen cream pie preparations, they are preferred to other starches. A pregelatinized starch phosphate has been developed (131) which is dispersible in cold water, for use in instant dessert powders and icings and nonfood uses such as core binders for metal molds, in papermaking to improve fold strength and surface characteristics, as a textile size, in aluminum refining, and as a detergent builder. 

Starch sodium phosphate monoesters [11120-02-8] are prepared by heating mixtures of 10% moisture starch and sodium monohydrogen and dihydrogen phosphates or sodium tripolyphosphate. Starch phosphate monoesters are used primarily in foods, such as pudding starches and with oH-in-water emulsions. 

Figure 2. Erythrocytic acid phosphatase schematic. A schematic drawing illustrating typical results of an EAP determination in a 13%, 1mm starch gel prepared in 0.24M Nall TO, 0.15M trisodium citrate tannic acid buffer diluted 1 100. The electrophoresis is carried out for 41/2 hr at approximately 410 V. The gels are stained by the fluorescence produced after enzymatic hydrolysis by methylumbellifertjl phosphate at 37° C for 1V2 hr.

Prepare the starch substrate by diluting the 20 g l-1 starch solution prepared in step 1 with an equal volume of pH 7.0 phosphate buffer solution. This results in a working starch concentration of 10 g 1 1. Add 2 ml of the starch solution to each of the test tubes. 

When the starch solution prepared in step 1 has cooled, add the solution (250 ml) to 250 ml of 0.8 M phosphate buffer in a 1-liter Erlen-meyer flask... 

Chlorinated and/or oxidized starches crosslinked with glyoxal were used to produce a high-strength size for paper.573 Coating adhesives were also prepared by crosslinking glycidyl esters.1385 In addition, esters of starch with inorganic acids (such as starch phosphates) were crosslinked with various aliphatic and aromatic aldehydes in the presence of urea, melamine and similar compounds.1322... 

Phosphorus in starch is found in different forms, mainly starch phosphate monoester, phospholipids, and inorganic phosphate. 31P NMR spectroscopy was used to identify each of these forms in alpha-dextrins prepared from starches of different sources.128 Quantitative analysis was possible in DMSO solution. 

Other widely applied preparations produced upon esterification of starch are starch phosphates [19, 26], Depending on the mode of phosphoric acid residues incorporation into a polymer structure, there may be distinguished monostarch (Fig. 7.2) and distarch phosphates (Fig. 7.3) [18]. 

The specific activities of purified preparations of human parotid and pancreatic amylases towards Amylose Azure, Remazol Brilliant Blue starch, phosphate-derivatized starch, and cross-linked starch have been measured. The activities varied with the physical state of the substrate the parotid enzyme exhibited a higher specific activity towards all soluble starches, whereas the pancreatic amylase was more active towards insoluble chromogenic starches. Variations in the enzyme-substrate interactions support the view that there is a configurational difference between the amylases this may be useful in determining the proportions of these amylases in normal and pathological body fluids. 

Landerito NA, Wang Y-J. 2005. Preparation and properties of starch phosphates using wrixy, common, and high-amylose corn starches. II. Reactive extmsion method. Cereal Chem 82 271-276. 

Tablets were prepared either with an insoluble (dicalcium phosphate dihydrate), a soluble (6-lactose) or a moderately soluble filler-binder (a-lactose monohydrate). As a disintegrant four different starches (com, rice, potato and tapioca) were used. As a comparison the effect of two super-disintegrants (crospovidone and sodium starch glycolate) was studied. The disintegrants were added at two concentration levels. The compression load was adjusted in order to obtain tablets with comparable initial cmshing strengths.

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