Waxy maize starch

Acetylation was the first form of monosubstitution used in food starches. Waxy maize acetylated distarch adipates came into use in the mid-1950s, driven by demand for... 

The variation between the starch from different plants is considerable. The percentage of amylose varies from 27% in maize starch through to 22% in potato starch and 17% in tapioca starch. Waxy maize starches are unusual in that they are almost pure amylopectin. This is extremely convenient because it avoids the need to separate amylopectin from amylose chemically. 

Achayuthakan et al. (2006) studied vane yield stress of Xanthan gum-stareh dispersions. The intrinsic viscosity of Xanthan gum was determined to be 112.3 dl/g in distilled water at 25°C. In addition, the size of the granules in the dispersions of the studied starches waxy maize (WXM), cross-linked waxy maize (CWM), and cold water swelling (CWS) were determined. The values of yield stress of the starch-xanthan dispersions relative to those of the starch-water dispersions (YSA"S0) and relative mean granule diameters (D/DO) plotted against values of c[ ] of xanthan gum are shown in Figure 4-42. With the values of YS/YSO being less than 1.0, there was no synergism between CLWM starch and xanthan gum. 

ANG 06] Angeller H., Molina-Boisseau S., Dole P., etal, Thermoplastic starch-waxy maize starch nanocrystals nanocomposites . Biomacromolecules, vol. 7, no. 2, pp. 531-539,2006. 

Angellier H, Molina-Boisseau S, Lebrun L et al (2005) Processing and structiual properties of waxy maize starch nanocrystals reinforced natural rubber. Macromolecules 38 3783-3792 Angellier H, Molina-Boisseau S, Dole P et al (2006) Thermoplastic starch-waxy maize starch nanocrystals nanocomposites. Biomacromolecnles 7 531-539... 

H. Angellier, S. Molina-Boisseau, P. Dole, and A. Dufresne, Thermoplastic starch-waxy maize starch nanocrystals nanocomposites. Biomacromolecules 7, 531-539 (2006). 

Starch nanocrystals has been used in different environmental-friendly polymers such as waterborne polyurethane (Chen et al. 2008) (also called organic solvent free polyurethane), starch (waxy maize, AngeUier et al. 2006 Viguie et al. 2007 Garcia et al. 2009a), pullulan (Kristo et al. 2007) (obtained by starch fermentation), PLA (Yu et al. 2008), polyvinyl alcohol (PVA) (Chen et al. 2008), and soy protein isolate (Zhen et al. 2009), but we will focus on its use on starch matrices. 

The most common sources of starch to develop the nanocomposites matrix are pea starch, waxy maize starch, cassava starch, normal maize and potato starch. (Chen et al. 2009 Garcia et al. 2009a, b Jayakody and Hoover 2002 He et al. 2012). 

Compare the viscoamylographic properties of regular maize starch, waxy maize starch, wheat starch, and rice starch. Why are waxy starches highly demanded by the food industry ... 

Synonyms Waxy com starch Waxy maize starch... 

Washing soda. See Sodium carbonate Water glass. See Sodium metasilicate Sodium silicate Waxes, camauba. See Camauba (Copemica cerifera) wax Waxes, microcrystalline. See Microcrystalline wax Waxes, montan. See Montan wax Waxes, montan fatty acids. See Montan acid wax Waxy corn starch Waxy maize starch. See Com starch, waxy Welan gum CAS 96949-22-3... 

Similar materials are available based on potato starch, eg, PaseUi SA2 which claims DE below 3 and has unique properties based on its amylose—amylopectin ratio pecuhar to potato starch. The product contains only 0.1% proteia and 0.06% fat which helps stabilize dried food mixes compounded with it. Another carbohydrate raw material is waxy-maize starch. Maltodextrias of differeat DE values of 6, 10, and 15, usiag waxy-maize starch, are available (Staley Co.). This product, called Stellar, is offered ia several physical forms such as agglomerates and hoUow spheres, and is prepared by acid modification (49). Maltodextrias based oa com starch are offered with DEs of 5, 10, 15, and 18 as powders or agglomerates (Grain Processing Corp.). 

In industrial production of acid-modified starches, a 40% slurry of normal com starch or waxy maize starch is acidified with hydrochloric or sulfuric acid at 25—55°C. Reaction time is controlled by measuring loss of viscosity and may vary from 6 to 24 hs. For product reproducibiUty, it is necessary to strictly control the type of starch, its concentration, the type of acid and its concentration, the temperature, and time of reaction. Viscosity is plotted versus time, and when the desired amount of thinning is attained the mixture is neutralized with soda ash or dilute sodium hydroxide. The acid-modified starch is then filtered and dried. If the starch is washed with a nonaqueous solvent (89), gelling time is reduced, but such drying is seldom used. Acid treatment may be used in conjunction with preparation of starch ethers (90), cationic starches, or cross-linked starches. Acid treatment of 34 different rice starches has been reported (91), as well as acidic hydrolysis of wheat and com starches followed by hydroxypropylation for the purpose of preparing thin-hoiling and nongelling adhesives (92). 

Starch acetates [9045-28-7] are made by reaction of starch with acetic anhydride. Starch acetates are used in foods to provide paste clarity and viscosity stabiHty at low temperatures. A waxy maize starch acetate is most commonly used. Waxy maize starch acetates for food use are often cross-linked. Acetylated starches are also widely used in warp sizing of textiles. 

Definite proof that the interchain linkage is 6 —> 1-a-D has been obtained by Wolfrom and coworkers,91 who have isolated crystalline /3-isomaltose [6-0-(/3-D-glucopyranosyl)-D-glucose] octaacetate (in 1 % yield) from the mild acetolysis of waxy maize starch and have presented evidence that... 

In this connection, it should be noted that Wolfrom and Thompson9611 have recently claimed the isolation of 0.1% of nigerose (a 3 — 1-a-disac-charide) from the hydrolysis of waxy-maize starch. 

Although it has been found that the separated amylose component can be readily orientated to yield fiber patterns, amylopectin usually gives poor or amorphous patterns. In the granule, however, amylopectin does exhibit crystallinity, since waxy maize starch gives a diffraction pattern and other waxy starches behave similarly.193 -195 (This suggests that the branch points in the amylopectin molecule may be in the amorphous part of the granule.)... 

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... 

Starch is the major energy store of plants chemically it is a polymer of glucose and occurs in two separate forms, amylose and amylopectin. The ratio of the two types depends on the plant that the starch has come from typically starch is 20 30% amylose and 70-80% amylopectin but there are amylomaizes with more than 50% amylose while waxy maize produces almost pure amylopectin with less than 3% amylose. 

If starch with different properties is required then either a different plant source must be used, e.g. waxy maize instead of potato, or a way of altering the starch produced by a plant must be found. 

Starches with modified properties can be obtained in several ways. One way is to use a source with starch that has different properties. Examples of this are waxy maize, which gives almost pure amylopectin, and tapioca. These are still starch in food law. 

Obtaining Different Properties in the Starch. One method of obtaining a starch with different properties is the biological method of using a different type of plant. The best example of this is waxy maize, which yields a starch that is nearly pure amylopectin. The other method is to chemically modify the starch. Chemically modified starch is normally declared as modified starch . A whole range of modified starches are available. There is of course no bar to chemically modifying a starch from a special source. 

Non-gelling Starches. These products are intended for uses where the starch replaces a gum like gum acacia. A typical product for this use might be an oxidised waxy maize starch. 

Amylodextrins from waxy-maize starch (A type) and potato starch (B type) retain the same diffraction pattern as that of the parent starch. On separation of a starch to give an amylodextrin, the... 

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