Starch manufactureStarch is a high molecular mass carbohydrate produced by plants as a food store. Starch and its derivatives are used in several sectors including food, paper and textile manufacture. Purified starch is usually a white powder that can be used as a thickening agent in the food industry.
Starch used in food processing is usually chemically treated or “modified” to enhance desirable functional properties. Hydrolysis of starch by acid and/or enzymes yields a variety of sugar syrups. Incomplete hydrolysis yields a mixture of glucose, maltose and non-hydrolysed fractions called dextrins. Germ is a co-product of starch manufacture, and can be used to produce oils. Other co-products are fibre, gluten and de-fatted meal which are all used or sold on for other uses, including animal feed.
Maize or potato is usually used as the raw material for modified starches for food applications.
The quality of starch is very important for the suitability in the product. A lot of damaged starch gives a good soluble starch at low temperatures, but it is very sensitive. Undamaged starch on the other hand is more soluble at high temperatures (80ºC). Besides the content of starch affected by amylases is of influence for further processing.