Starch is the most common carbohydrate in the human diet and is contained inmany staple foods. The major sources of starch intake worldwide are the cereals (rice, wheat, and maize) and the root vegetables (potatoes and cassava). Many other starchy foods are grown, some only in specific climates, including acorns, arrowroot, arracacha, bananas, barley, breadfruit, buckwheat, canna, colacasia, katakuri, kudzu, malanga, millet, oats, oca, polynesian arrowroot, sago, sorghum, sweet potatoes, rye, taro, chestnuts, water chestnuts and yams, and many kinds of beans, such as favas, lentils, mung beans, peas and chickpeas.
Widely used prepared foods containing starch are bread, pancakes, cereals, noodles, pasta, porridge and tortillas.
The starch industry extracts and refines starches from seeds, roots and tubers, bywet grinding, washing, sieving and drying. Today, the main commercial refined starches are corn starch, tapioca,arrowroot, and wheat, rice, and potato starches. To a lesser extent, sources of refined starch are sweet potato, sago and mungbean. To this day, starch is extracted from more than 50 types of plants.
Untreated starch requires heat to thicken or gelatinize. When a starch is pre-cooked, it can then be used to thicken instantly in cold water. This is referred to as a pregelatinized starch.
Starch canbe hydrolyzed intosimpler carbohydrates by acids,various enzymes,or a combination of the two. The resulting fragments are known as dextrins. The extent of conversion is typically quantified by dextrose equivalent (DE), which is roughlythe fraction of the glycosidic bonds in starch that have beenbroken.
These starch sugars are by far the most common starchbased food ingredient and are used as sweeteners in many drinks and foods. Theyinclude: maltodextrin, dextrose, high fructose syrup and sugar alcohols, , suchas maltitol, erythritol, sorbitol, mannitol and hydrogenated starch hydrolysate, aresweeteners made by reducing sugars.