Waxy starches

SW- waxy corn starch, SWNPs- starch nanopartides. Cel- microcrystaUine cellulose, CelNPs- cellulose nanopartides, CB- carbon black, SWAcNPs- waxy starch acetate nanopartides, CelAcNPs cellulose acetate nanopartides. 

Fig. 15. TGA curve of pure waxy starch and Ag-waxy starch nanocomposites with different concentrations of silver ion precursor (moles of AgN03)...

Fig. 16. FT-IR spectra of pure waxy starch and waxy starch metal nanocomposites...

Allen et al. (2007) produced puffed snack foods with com starch and pregelatinized waxy starch, WPC and instantized WPC, and protein concentrations of 16%, 32%, and 40% and showed that the air cell size, extru-date expansion ratio, and water solubility index decreased proportionally as protein and com starch levels increased. Protein concentration significantly affected total soluble protein, water absorption index, and water-soluble carbohydrate. A covalent complex between amylase and protein formed in the presence of cornstarch, but protein-protein interactions appeared with the presence of low levels of pregelatinized waxy 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.)... 

Base starches used for cationics are corn, potato and waxy. Corn remains dominant world wide although potato is a close second. Waxy starches are mainly used in the USA. The amount of waxy starch available is dependent on demands for waxy starch in the food industry. 

Ferrari, F., et al. 1997. Technological induction of mucoadhesive properties on waxy starches by grinding. Eur J Pharm Sci 5 277. 

Paste properties of native starches from different botanical origins have been reviewed.92,133 Relevant to practical usage of starch, the most important paste properties are viscosity, texture, paste transparency, resistance to shear and tendency to retrograde. In terms of texture, the translucent potato starch pastes can be described as cohesive, long-bodied, stringy and rubbery. Other root, tuber and waxy starches give pastes of similar texture to that of potato starch, but are generally less cohesive. On the other hand, pastes from common cereal starches are opaque and can be described as noncohesive and short- and heavy-bodied. These and other properties of several native starches are summarized in Table 8.1. 

Figure 8.9 A typical DSC trace of a cereal non-waxy starch (50% w/w) showing multiple melting transitions and the respective structural domains undergoing a phase change.

Uses of partial-waxy and waxy wheat in Asian noodles, bread and tortillas have been reviewed.269,270,298 French bread made from double-null partial waxy wheat flour retained 1-2% more moisture in its crumb in 24 hours compared to bread from a wild type flour. French bread made from the mutant wheat had a softer crumb immediately and up to 48 hours after baking.299 Wheat noodles are made from flour and low levels of salts, so starch plays a major role in noodle quality. Flours from partial waxy wheats with —10% protein and 21-24% apparent amylose (starch basis) are favored for white salted (sodium chloride) noodles because partial waxy starch swells during cooking somewhat more than non-waxy wheat starch. For good appearing noodles, the flour should be from a white wheat low in polyphenol oxidase, and... 

Hydrophobic starches are another new class of starches for use on the size press. Some grades are based on waxy starches and are esterified. Hydrophobic starches provide improvements in water, ink and solvent holdout, as well as decreased sheet porosity. 

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