By Melissa Hillebrand
Fiber's rising popularity has given attention to resistant starch. Containing many of the same nutritional characteristics as fiber, resistant starch gives healthful and functional benefits to consumers and bakers. Similar to some types of fiber, resistant starch, defined as the sum of starch and products of starch degradation, ferments in the large intestine, resisting digestion in the small intestine.
Resistant starch has four different classifications:
•RS1 ¯ resistant starch physically protected by whole grains.
•RS2 ¯ granular resistant starch, which can be found in green bananas.
•RS3 ¯ nongranular, retrograded or crystalline resistant starch, which can be found in bread crusts, cooked and cooled potatos and ready-to-eat breakfast cereals.
•RS4 ¯ created from various sources, including wheat, potato and tapioca.
Some types of resistant starch deliver-fiber. One resistant starch supplier says that foods containing RS2 or RS4 can be measured and labeled with fiber. Products with RS1 can be labeled as containing fiber if the whole grains are intact. "But if they are finely ground and processed, it loses its protective shell and does not deliver resistant starch or fiber," the supplier says. Foods containing RS3 cannot be labeled with fiber. For bakers looking to incorporate resistant starch into their formulations, suppliers offer RS4.
Similar to fiber, resistant starch promotes health. Studies show that natural resistant starch slowly releases low levels of glucose into the blood after consumption. Resistant starch lowers the glycemic impact on blood sugar, which may reduce the risk of cardiovascular disease and obesity.
Natural resistant starch also increases insulin sensitivity. Similar to its impact on glucose levels, resistant starch releases low levels of insulin into the blood. Consumption of resistant starch makes the body more sensitive to insulin, one supplier says.
The supplier's company offers two types of resistant starch that are prebiotic. Studies have proven that these types of resistant starch increase good bacteria levels and decrease bad bacteria levels in the large intestine, she says. Studies also show that one of these resistant starches increases fat burning in the human body.
Another healthful benefit brought on by this ingredient is improvement in colon health. Resistant starch lowers pH values and builds a strong barrier in the large intestine during fermentation. Resistant starch that acts as a fiber produces butyrate, a short-chain fatty acid that is the colon's preferred energy source. Butyrate prevents tumor growth in the large intestine, where it is fermented.
Incorporating resistant starch
Resistant starch not only provides health benefits, but functional ones as well. Resistant starch can be substituted for flour in any bakery application. However, when bakers formulate their products with resistant starch, they must replace some of the gluten that is found in flour, one resistant starch supplier says.
Substituting resistant starch for flour results in no loss of taste or appearance. One manufacturer says, for example, that in cookies, "the incorporation of resistant starch from wheat and potato gives you the same spread and cracking pattern on the surface of the cookies."
Another feature of resistant starch is its low water-holding capacity. For bakers looking to reduce the amounts of water in their bakery foods, another manufacturer offers a resistant starch that has an even lower water holding capacity than typical resistant starch varieties. It is ideal for bread and cereal applications.
This manufacturer also offers a resistant starch that can be used as a replacement for eggs and flour. It is ideal for bakery foods with a baked texture and high moisture content, such as cookies, muffins and brownies.
Because resistant starch is not digestible, it can lower calories in a bakery food. Bakers can lower their products' net carbohydrates by incorporating resistant starch into their formulas.
Resistant starch offers a variety of benefits in bakery formulas. The ingredient gives nutritional benefits, such as producing butyrate, and is convenient to incorporate into bakery formulations. Because resistant starch can be substituted for flour, it is ideal for any bakery application.