For the Urhobo cuisine dish known as starch, see usi (food).
Starch
Cornstarch being mixed with water
Identifiers
CAS Registry Number
9005-25-8 Yes
ChemSpider
EC number 232-679-6
RTECS number GM5090000
Properties
Chemical formula
(C
6H
10O
5)
n
Molar mass variable
Appearance white powder
Density 1.5 g/cm3
Melting point decomposes
Solubility in water
insoluble (see starch gelatinization)
Hazards
Safety data sheet ICSC 1553
Autoignition
temperature
410 °C (770 °F; 683 K)
US health exposure limits (NIOSH):
PEL (Permissible)
TWA 15 mg/m3 (total) TWA 5 mg/m3 (resp)[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes verify (what is: Yes/?)
Infobox references
Structure of the amylose molecule
Structure of the amylopectin molecule
Starch or amylum is a carbohydrate consisting of a large number of glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants as an energy store. It is the most common carbohydrate in human diets and is contained in large amounts in such staple foods as potatoes, wheat, maize (corn), rice, and cassava.
Pure starch is a white, tasteless and odorless powder that is insoluble in cold water or alcohol. It consists of two types of molecules: the linear and helical amylose and the branched amylopectin. Depending on the plant, starch generally contains 20 to 25% amylose and 75 to 80% amylopectin by weight.[2] Glycogen, the glucose store of animals, is a more branched version of amylopectin.
Starch is processed to produce many of the sugars in processed foods. Dissolving starch in warm water gives wheatpaste, which can be used as a thickening, stiffening or gluing agent. The biggest industrial non-food use of starch is as adhesive in the papermaking process. Starch can be applied to parts of some garments before ironing, to stiffen them.