Waxy starch dextrin

Langourieux and Crouzet [20] used a dynamic method (exponential dilution) to study the effect of modified and waxy starches, dextrin, dextran, hydroxypropyl celluloses, galactomanans, and P-cyclodextrin on flavor release. Their method involved measuring the dilution of the headspace above a sample over time. In this method, the greater the release of test compounds from a solution, the slower the headspace above the solution could be depleted of these test compounds. 

Waxy starch dextrins are similar to dextrins made from non-waxy starch, but have a greater viscosity stability than the corresponding regular dextrin. Envelope front seals, stamps, and gummed sheets are some uses. 

Sealing tape has 35 to 90 pounds per ream of kraft paper as a substrate, whereas, reinforced sealing tape is based on a bonded laminate of kraft paper, reinforcing fibers, and kraft paper. The adhesives applied to these substrates may be thin-boiling, waxy starches alone, or blended with a soluble dextrin (5). More recently, blends of a soluble dextrin with oxidized potato or a hydrox-ypropyl ether of an oxidized potato starch are being used (9). Also, the acetate or succinate of an oxidized waxy starch may be used (15) as well as specially produced waxy starch acrylamide graft copolymer products (16). 

The only example of this technique applied to the amylose component is that already described, of the action of Z-enzyme on the /3-limit dextrin. In the case of amylopectin, enzymic methods enable a distinction to be made between the proposed laminated and highly ramified structures (I and III, in Fig. 1, page 352). The method used by Peat and coworkers101 involves the successive action of /3-amylase and R-enzyme on waxy maize starch. /3-Amylolysis will degrade A-chains down to two or three units from the 6 —> 1-a-D interchain linkages. These latter linkages will protect the... 

When the / -limit dextrin of waxy-maize starch reacted with exo-maltohexahydrolase (EC 3.2.1.98), which can by-pass some a-(l- 6) linkages, the branched a-D-gluco-oligosaccharides expected, namely, 64-a-maltosylmaltopentaose (102), 63-a-maltotriosylmaltotetraose (103), 64-a-maltosylmaltohexaose (104), and 63-a-maltotriosylmaltopentaose... 

There have been several examinations of the structure of Nageli dextrin,405407 which is prepared by the prolonged action of acid on granular starch. In one study,405 there was separated from waxy maize a branched fraction that was resistant to pullulanase action. As this fraction contained some molecules having two branch points that were in close proximity, it was considered that this may have hindered hydrolysis, and that it could be of relevance to studies on the structure of the original amylopectin. 

Figure 6.13 H PAEC-EN-PAD chromatograms of Naegeli dextrins of (a) waxy maize (A-type) (b) ae waxy maize (B-type) and (c) banana (C-type) starches.316...

The doubly branched dextrins, 64,66-di-a-D-glucopyranosylmaltohexaose and 63,65-di -a-D-glucopyranosylmaltopentaose, isolated by Kainuma and French17 after action of porcine pancreatic a-amylase on waxy maize starch, established that the a-(l—>-6) branch linkages could be as close as having one glucosyl unit between them. No saccharides were found that indicated that the branch linkages could be adjacent to each other. 

Dextrinization of tapioca starch is well-known. The difficulty in dextrinizing corn starch,64 and the relative ease of tapioca starch conversion,65 have been described. The near-absence of lipids, which interfere with the dextrinization process, has given tapioca dextrins an advantage in stability and color because of their ease of manufacture and control. However, the economics of base starch supply have resulted in a significant shift to waxy com starch as a base for industrial dextrins, even though... 

Candy coatings are applied via repeated, successive application of dextrin and sugar solutions, followed by drying. Dextrins and monosubstituted starch hydrolyzates are used in candy coatings because of their clear, appetizing films. In this application, clarity, sheen and reduced cracking are desired. Oxidized waxy maize starches are also used.12 Starch used as an impressionable bed for casting candies is typically dent com starch with several tenths of a percent of mineral oil. The oil causes the starch to retain the imprinted shape for a more precisely formed candy piece. 

Another common method for determination of alpha-samylase involves measurement of the diminution of the iodine-stainability of whole starch or amylopectin )8-limit dextrin. These methods are useful, as very small quantities of alpha-amylase may be estimated in this way. They are comparative, and cannot be used to determine rates of bond scission, unless they are carefully calibrated by a method that measures reducing end-groups. Such a calibration has been made for the action of hog-pancreas alpha-amylase on waxy-maize starch, although the validity of the reducing-power determinations, made with iodine and thiosulfate, has been confirmed for maltose only thus, it is not yet known whether the calibration is actually valid for the experimental system in which larger oligomers, for example, the triose and tetraose, are also formed. 

For practical large-scale production of the Schardinger dextrins, the best source is whole unmodified starch (potato, defatted corn, or waxy maize). The cereal starches must be defatted prior to use, because otherwise a considerable quantity of an insoluble coagulum forms during the digestion. ... 

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