Native com starch

Nonfood Uses. Native com starch is principally used in nonfood appHcations in mining, adhesives, and paper industries. Pregelatinized starch is chemically unmodified, but it is physically modified. Pregelatinized starches are used to decrease water losses in oil-weU drilling muds, in cold water-dispersable wallpaper pastes, and in papermaking as an internal fiber adhesive. 

Figure 15.5 High performance size-exclusion chromatography (HPSEC) of native com starch, and TPS with 20 per cent (Gli-20), 30 per cent (Gli-30) and 40 per cent glycerol (Gli-40). Reproduced with permission from Reference [108],...

Starch to native com starch were prepared, and sufficient water at 50 °C was then added to obtain a water content of 40%. The starch-water mixtures were then placed in a diffusion cell and the solubility and diffusion coefficients of CO were determined at pressures up tol6 MPa at 50 °C. The experimentally-measured solubility accounted for the estimated swollen volume the solubility increased with pressure. The solubility of CO showed no dependence on the degree of gelatinization of the starch. The diffusion coefficient of CO increased with the concentration of CO (which was pressure dependent) and decreased with increasing degrees of starch gelatinization. 

Surimi is fish paste from deboned fish used to make simulated crab legs and other seafood. For preservation the paste is blended with cryoprotectants, such as sucrose, sorbitol and phosphates, and frozen. To make the final product, the frozen paste is thawed, blended with starch and extruded as a film onto a belt. The belt takes the film into an oven that heat-denatures the fish protein and cooks the starch. The film is then rolled to form striations, shaped, colored and cut. Depending on the required distribution, the product is frozen or refrigerated. Potato and tapioca starch were used in surimi products 400 years ago, since they provided a cohesive, elastic matrix consistent with seafood. Frozen distribution has made the use of highly-stabilized, moderately crosslinked tapioca starch popular, alone or with native tapioca starch. Modified waxy maize products are used, as is unmodified com starch, for increased cuttability. Kim188 reported that the gel strengthening ability of starch correlates with starch paste viscosity. 

Commercial native tapioca and com starches from Thailand (Tesco) were purchased and used as received. Alumina powder (99.5% purity, Amarin, Thailand), wherein the particle size distribution is shown in Figure 1, was used as the ceramic raw material. Ceramic suspensions were prepared to different % solid loadings with sodium silicate (Amarin, Thailand) as a dispersant, having a fixed concentration of 3 wt.% on a dry alumina basis. The wt.% starch powders were added in different quantities 5 wt.%, 10 wt. %, 15 wt.% and 20 wt.% on a dry alumina basis, which corresponded to 69%, 66%, 63% and 60% solid loadings, respectively. Homogenization was carried out by ball... 

Nattapulwat, N. Purkkao, N. Suwithayapanth, O. Evaluation of native and carboxymethyl yam (Dioscorea esculenta) starches as tablet disintegrants. Silpakorn U. Sci. Tech. J. 2008, 2 (2), 18-25. Kottke, M.K. Chueh, H.R. Rhodes, C.T. Comparison of disintegrant and binder activity of three com starch products. Drug Dev. Ind. Pharm. 1992,18 (20), 2207-2223. 

Starch PoIy(ethyIene-vinylalcohol) copolymer, 56% VA waxy maize, native com and high-amylose starches extrusion-blended x-ray, DSC, SEM, TEM Phase separated starch domains. Oriented droplets, 0.05-5 jm in length (waxy maize), 0.05-1.2 pm domains (native com), <0.25 pm (high amylose) (81)... 

Dextrins obtained on y-irradiation of starch have been found to contain appreciable proportions of unidentified carbonyl residues. The properties of starch for starch-gel electrophoresis were improved by y-irradiation. The decreases in viscosity and iodine-absorption values, as well as the increased reducing properties, indicated that amylose and amylopectin are degraded by y-irradiation in the same way as native starches. Although each of the amylose and amylopectin components of amylomaize starch in y-irradiated and untreated samples was hydrolysed by a-amylase to the same extent, y-irradiated amylose had a low p-amylolysis limit. /-Irradiated amylomaize and com starches were hydrolysed to greater extents by a-amylase as the radiation dose was increased, and differences were detected in the products of enzymic degradation of amylomaize and corn starches following y-radiolysis. The water-soluble dextrins formed on y-irradiation of maize starch have been examined. ... 

The mechanical properties of starch-based plastics of native com, potato, waxy com arrd wheat starch, produced by compression moitlding of native starch and glycerol in the weight ratio 0 to 3 were strongly dependent on the water content and starch sotrrce [38]. 

Sweetening orange juice with cane sugar or glucose-fructose syrup from com starch lowers the 8( C) value of sugar, which is —25.5%o in the native juice (Table 18.45). On the other hand, the addition of beet sugar (C3-plant) can be recognized only via the 8( H) value. The addition of synthetic products from petrochemicals (8( C) —27 5%c) to foods from C3-plants cannot be detected via the 8( C) value, but via the 8( H) value in many cases. 

As com starch is a native agricultural product, inexpensive (about 10 cents lb ) and available annually in multimillion ton quantities it could be considered a replacement for petroleum-based plastics as starch-graft copolymers, starch-plastic composites, and starch itself. [52]. 

The solubihty and the diffusion coefficients of CO in starch-water mixtures were determined by Chen and Rizvi (2006a) using native and pregelatinized com starches for their experiments. Starch mixtures containing 50 50,75 25, and 100 0ratios of pregelatinized... 

Peterson SC, Fanta GF, Adlof RO, Felker FC. 2005. Identification of complexed native lipids in crystalline aggregates formed from jet cooked com starch. Carbohydr Polym 61 162-167. 

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