Food starches come from a variety of natural sources, including potatoes, corn, tapioca and grains. Natural starches are modified to improve the thickening power, creamy texture or functional attributes of food; when modified, they can be used in commercial food applications. Modified food starches are less expensive and more widely available than gums or other food stabilizers. The type used varies depending on its intended use in food processing.
Hybrid Starches
Hybrid food starches come mainly from corn. Hybridization is the process of crossing different strains of corn to develop a new variety. A unique variety of corn called waxy corn was discovered in 1908 in China, according to James BeMiller and Roy Whistler in their book "Starch: Chemistry and Technology." Waxy corn has thickening properties similar to tapioca. Waxy hybrids came to the United States during the 1940s and were combined with other strains of corn to produce high-amylose starches, which improve gelling and firming. These modified food starches are used in candies and fried foods. Various hybrid combinations are created for use in different types of products.
Chemically Modified Starches
Raw starches are chemically modified to control various elements of the starch for use in manufacturing. Some starches are chemically modified to reduce the viscosity or thickness of a fluid, so the food can be water-soluble or have a higher percentage of modified starch in the finished product. Chewing gum and other confections use chemically modified food starch to achieve the desired softness.
Cross-Linked Starches
Cross-linked starches bond one polymer chain to another chemically, joining two molecules. Cross-linking starches increases stability, which improves the texture of various commercially produced food products. Fruit pies, canned vegetables, soups, sauces and salad dressings are made using cross-linked starches to improve quality and texture. Cross-linking starches can stand up to overcooking or other extreme processing conditions.
Stabilized Starches
Stabilized starches increase the shelf life of food products. Stabilization is the modification of the starch with reagents that resist specific properties of the starch that are unwanted, such as the tendency to gel, turn to paste or seep fluids. This helps to keep commercially processed food tasting fresh, even after it has been frozen and thawed.
