Modified starch
Modified starch, also called starch derivatives, are prepared by physically, enzymatically, or chemically treating native starch to change its properties. Modified starches are used in practically all starch applications, such as in food products as a thickening agent, stabilizer or emulsifier; in pharmaceuticals as a disintegrant; or as binder in coated paper. They are also used in many other applications. Starches are modified to enhance their performance in different applications. Starches may be modified to increase their stability against excessive heat, acid, shear, time, cooling, or freezing; to change their texture; to decrease or increase their viscosity; to lengthen or shorten gelatinization time; or to increase their visco-stability. Modification methods Acid-treated starch (INS 1401), also called thin boiling starch, is prepared by treating starch or starch granules with inorganic acids, e.g. hydrochloric acid breaking down the starch molecule and thus reducing the viscosity. Other treatments producing modified starch (with different INS and E-numbers) are: dextrin (INS 1400), roasted starch with hydrochloric acid alkaline-modified starch (INS 1402) with sodium hydroxide or potassium hydroxide bleached starch (INS 1403) with hydrogen peroxide oxidized starch (INS 1404, E1404) with sodium hypochlorite, breaking down viscosity enzyme-treated starch (INS 1405), maltodextrin, cyclodextrin monostarch phosphate (INS 1410, E1410) with phosphorous acid or the salts sodium phosphate, potassium phosphate, or sodium triphosphate to reduce retrogradation distarch phosphate (INS 1412, E1412) by esterification with for example sodium trimetaphosphate, crosslinked starch modifying the rheology, the texture acetylated starch (INS 1420, E1420) esterification with acetic anhydride hydroxypropylated starch (INS 1440, E1440), starch ether, with propylene oxide, increasing viscosity stability hydroxyethyl starch, with ethylene oxide starch sodium octenyl succinate (OSA) starch (INS 1450, E1450) used as emulsifier adding hydrophobicity starch aluminium octenyl Succinate (INS 1452, E1452) cationic starch, adding positive electrical charge to starch carboxymethylated starch with monochloroacetic acid adding negative charge and combined modifications such as phosphated distarch phosphate (INS 1413, E1413) acetylated distarch phosphate (INS 1414, E1414) acetylated distarch adipate (INS 1422, E1422), hydroxypropyl distarch phosphate (INS 1442, E1442), acetylated oxidized starch (INS 1451, E1451). Modified starch may also be a cold-water-soluble, pregelatinized or instant starch which thickens and gels without heat, or a cook-up starch which must be cooked like regular starch. Drying methods to make starches cold-water-soluble are extrusion, drum drying, spray drying or dextrinization. Other starch derivatives, the starch sugars, like glucose, high fructose syrup, glucose syrups, maltodextrins, starch degraded with amylase enzyme are mainly sold as liquid syrup to make a sweetener. Examples of use and functionality of modified starch Pre-gelatinized starch is used to thicken instant desserts, allowing the food to thicken with the addition of cold water or milk. Similarly, cheese sauce granules such as in Macaroni and Cheese, lasagna, or gravy granules may be thickened with boiling water without the product going lumpy. Commercial pizza toppings containing modified starch will thicken when heated in the oven, keeping them on top of the pizza, and then become runny when cooled. A suitably modified starch is used as a fat substitute for low-fat versions of