An intermediate product formed during the hydrolysis of starch to sugars. There are three classes of dextrin:

  1. Amylodextrin, which gives a blue color with iodine and is soluble in 25% alcohol;
  2. Erythrodextrin, which gives a red color with iodine and is soluble in 55% alcohol; and
  3. Achrodextrin, which gives no color with iodine and is soluble in 70% alcohol.

Dextrin occurs as an intermediate product of starch hydrolysis and is achieved by either enzymatic action or by cooking. They do not have the same thickening qualities of starch and the molecules are also smaller than that of starch. It is formed when bread or cereals are browned or toasted.

The term dextrin describes a class of intermediate ingredients produced by treating starches with heat, acid, or enzymes. Synonyms for dextrins include starch gum, vegetable gum, and even tapioca.

Dextrin is used as a diluting agent for pills and capsules, as well as a thickener in creams and foam stabilizer in beer. It can also be found in baked goods, candy, gravies, pie fillings, poultry, puddings, and soups. FDA considers it Generally Recognized as Safe (GRAS) when used in amounts sufficient for its purpose.

Dextrin, any one of a number of carbohydrates having the same general formula as starch but a smaller and less complex molecule. They are polysaccharides and are produced as intermediate products in the hydrolysis of starch by heat, by acids, and by enzymes. Their nature and their chemical behavior depend to a great extent on the kind of starch from which they are derived. For example, some react with iodine to give a reddish-brown color, others a blue, and still others yield no color at all. For commerical use dextrin is prepared by heating dry starch or starch treated with acids to produce a colorless or yellowish, tasteless, odorless powder which, when mixed with water, forms a strongly adhesive paste. It is used widely in adhesives, e.g., for postage stamps, envelopes, and wallpapers, and for sizing paper and textiles.