Modified Wheat Starch
What is Modified Wheat Starch?
Modified wheat starch is the carbohydrate of the wheat kernel, isolated and modified for specific uses. The modification is done physically, enzymatically, or chemically, to either enhance or diminish attributes of the starch. The result is a variety of starches that can help with thickening, gelling, adhesion, moisture control or encapsulation.
These starches are found in a variety of batters, doughs, breakfast cereals, toppings, soups, sauces, vitamins and flavors. Modified wheat starches are also used in cosmetic products, construction products, manufacturing and paper products.1
Although starches were discovered thousands of years ago, their first uses were not for food. Starch glue was used by ancient Egyptians to adhere papyrus. The Romans extracted starch from grain in 170 BC. However, the first recorded discovery came along in 1804, by French chemist Bouillon Lagrange. Modified starches were discovered by Russian chemist Gottlieb Kirchhoff, who produced sugar from potato starch with acid hydrolysis.
Wheat was the most popular and widespread starch for many years, due to the abundance of the grain. As cultivation of potatoes and maize grew during the 18th century, they became common sources of starch as well. As processed and packaged foods began booming, the creating a need for specific attributes from the carbohydrate. The modified industry grew from there, with the FDA regulating the types of modifications allowed for food use.1
Production of modified wheat starch depends on the type being made and the process used. Dry and wet chemical process are used, as well as drum drying and extrusion methods. Acetylated, hydroxy propyl, sodium starch, acid thinned, bleached, oxidized, or combinations of some of these are all ways to modified wheat starches. The goal of these modifications is to control the starch’s reaction sites or influence the amylose or amylopectin molecules in the starch.2
The variety of modifications to wheat starches have different desired effects on the final product. The starches can range from having a low viscosity and restricted swelling to create a crispy coating, to a high viscosity and clarity pregel starch to thicken foods.3
Three types of modified starches are:4
Hydrolyzed starches: used in products with a high concentration of starch, they are usually a high-force gel with low viscosity, making it more dispersive without becoming too thick.
Intercrossed starches: make the viscosity more stable and improve the structure, as well as increasing the level of cross bonds.
Etherified starches: increases stability of the gel at a low temperature, helping retain moisture. They are good for improving freeze-thaw stability, and help create soft, creamy textures.
The more starch is oxidized, the more adhesion is achieved in products. Modified wheat starch that is high amylose resistant helps lower the glycemic index.2
Modified wheat starch must be labeled as such on the package. All modified starches are regulated by the FDA, under the Food Additives Amendment. Read the full list of requirements and specifications.
- Whistler, Roy Lester., James N. BeMiller, and Eugene F. Paschall. Starch: Chemistry and Technology. Orlando: Academic, 1984.
- Carver, Brett Frederick. “New Uses for Wheat and Modified Wheat Products.” Wheat: Science and Trade. Ames, IA: Wiley-Blackwell, 2009.
- Tester, R. “The Effects of Non-starch Polysaccharides on the Extent of Gelatinisation, Swelling and α-amylase Hydrolysis of Maize and Wheat Starches.” Food Hydrocolloids 17.1 (2003): 41-54.
- Yousefi, A.r., and S.m.a. Razavi. “Steady Shear Flow Behavior and Thixotropy of Wheat Starch Gel: Impact of Chemical Modification, Concentration and Saliva Addition.” Journal of Food Process Engineering J Food Process Eng 39.1 (2015): 31-43.