**Historical and Industrial Aspects of Starch:**
– Starch has a rich historical background, dating back to ancient civilizations like Egypt and Rome.
– Industrial processing of starch involves extracting it from various plants on a large scale.
– Significant quantities of starch are processed annually, with the EU producing 11 million tonnes in 2011 and the US producing 27.5 million tons in 2017.
– The majority of starch is used in food applications like glucose syrups, with a portion utilized for ethanol production.
– Enzymes play a crucial role in converting starch into refined products like maltodextrin and syrups through processes like liquefaction and saccharification.
**Biological Aspects of Starch:**
– Starch serves as an energy store in plants, stored in semicrystalline granules like amyloplasts in various plant parts.
– Starch granules consist of amylose and amylopectin, which are made bioavailable as needed.
– Plants synthesize starch in storage tissues and green tissues using glucose 1-phosphate and starch synthases.
– Degradation of starch involves the release of glucose from granules through enzymes like GWD, PWD, BAM, DPE1, and ISA.
– Starch biosynthesis involves granule initiation, coalescence, phase transition, and expansion, with proteins like MFP1 and PTST2 playing key roles.
**Food and Dietary Aspects of Starch:**
– Starch is a common component of the human diet, found in cereals and root vegetables grown worldwide.
– Resistant starch, found in uncooked plants, supports gut microbes and offers health benefits like improved insulin sensitivity.
– Highly processed foods impact starch digestibility and energy absorption, influencing health outcomes.
– Starch sugars like corn syrup are widely used in prepared foods, with potential implications for health like insulin resistance.
– Starch is utilized as a food additive for thickening, stabilizing, and sweetening various food products.
**Starch Applications Beyond Food:**
– Starch finds extensive non-food applications, such as in papermaking where both modified and unmodified starches are used.
– Clothing starch, warp sizing agents in textiles, and viscosity adjustment in drilling fluid are among the diverse non-food applications of starch.
– Starch adhesives are crucial in various industries, including corrugated board production.
– Synthetic starch production offers a more efficient alternative to traditional methods, with potential for diverse applications beyond food.
**Chemical Properties and Safety Considerations:**
– Chemical tests like the iodine test and Benedicts test are used to detect the presence of starch based on color changes.
– Safety regulations by organizations like OSHA and NIOSH set exposure limits for starch in the workplace to protect workers.
– Compliance with exposure limits is crucial for maintaining workplace safety and safeguarding against the harmful effects of starch exposure.
– Research on starch properties, synthesis, and metabolism contributes to scientific knowledge and informs industrial applications.
– Understanding starch functionality and characteristics is essential for various industries and researchers working in the field.
Starch or amylum is a polymeric carbohydrate consisting of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants for energy storage. Worldwide, it is the most common carbohydrate in human diets, and is contained in large amounts in staple foods such as wheat, potatoes, maize (corn), rice, and cassava (manioc).
| |
| Identifiers | |
|---|---|
| ChemSpider |
|
| ECHA InfoCard | 100.029.696 |
| EC Number |
|
| RTECS number |
|
| UNII | |
CompTox Dashboard (EPA)
|
|
| Properties | |
| (C 6H 10O 5) n | |
| Molar mass | Variable |
| Appearance | White powder |
| Density | Variable |
| Melting point | decomposes |
| insoluble (see starch gelatinization) | |
| Thermochemistry | |
Std enthalpy of
combustion (ΔcH⦵298) |
4.1788 kilocalories per gram (17.484 kJ/g) (Higher heating value) |
| Hazards | |
| 410 °C (770 °F; 683 K) | |
| NIOSH (US health exposure limits): | |
PEL (Permissible)
|
TWA 15 mg/m3 (total) TWA 5 mg/m3 (resp) |
| Safety data sheet (SDS) | ICSC 1553 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
| |
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. Glycogen, the energy reserve of animals, is a more highly branched version of amylopectin.
In industry, starch is often converted into sugars, for example by malting. These sugars may be fermented to produce ethanol in the manufacture of beer, whisky and biofuel. In addition, sugars produced from processed starch are used in many processed foods.
Mixing most starches in warm water produces a paste, such as wheatpaste, which can be used as a thickening, stiffening or gluing agent. The principal non-food, industrial use of starch is as an adhesive in the papermaking process. A similar paste, clothing or laundry starch, can be applied to certain textile goods before ironing to stiffen them.