Maize starch, modified

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). 

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. 

In Table V, the mechanical properties of particleboard bonded with nonemulsifiable diisocyanate modified with maize starch are given. The extender content for the diisocyanate was up to 20%. However, with increasing extender content, the internal bond of the boards decreased, and the thickness swelling increased the boards had V100 quality. First tests with adhesives of diisocyanates and starch were encouraging, and more attempts in developing new glue formulations... 

Da Silva, P. M. S., Oliveira, J. C., and Rao, M. A. 1997. The effect of granule size distribution on the rheological behavior of heated modified and unmodified maize starch dispersions. J. Texture Stud. 28 123-138. 

Statches ftom different plant sources differ in their amylose/ amylopectin ratio. For example, com starch contains about 27% amylose, potato starch about 22%, and tapioca statch about 17%. In contrast, waxy com statch contains almost entirely amylopectin, with no amylose. These diffetences modify the physical properties of the statches such that the various types may not be interchangeable in a given pharmaceutical application. For example, amylose-rich maize starch has been studied as a potential tablet film-coating ingtedi-... 

Bio-sorb double-dressed, white maize starch Fluidamid R444P Keoflo ADP Meritena modified starch dusting powder Pure-Dent B851 starch-derivative dusting powder sterilizable corn starch. 

Sterilizable maize starch is a modified corn (maize) starch that may also contain up to 2.0% of magnesium oxide. 

Sterilizable maize starch is a chemically or physically modified corn (maize) starch that does not gelatinize on exposure to moisture or steam sterilization. Sterilizable maize starch is primarily used as a lubricant for examination and surgeons gloves although because of safety concerns unlubricated gloves are now generally recommended. It is also used as a vehicle for medicated dusting powders. 

Corn starch (maize starch) is physically or chemically modified by treatment with either phosphorus oxychloride or epichlor-... 

Geiex31. [Am. Maize Finds.] Modified amioca starch. 

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