Maltodextrins are glucose polymers—small- to medium-chain lengths of glucose units—that are totally digestible. They provide approximately four calories per gram and are metabolized by the body the same as glucose. These neutral-tasting, non-sweet, cold-water-soluble carbohydrates can be formulated into all types of beverages to increase carbohydrate calories for stored energy.
“The advantages of maltodextrins are even more evident when used in beverages designed for consumption during sports events,” says Armstrong. “Many articles have been published on the need for fluid, energy and electrolyte balance for endurance and optimal performance. In many of these studies, glucose polymers have been shown to be effective in increasing endurance.
“One of the most-important characteristics of sports beverages consumed during an event is the product’s osmolality,” continues Armstrong. “Normal body fluids have an osmolality of 275 to 298 mOsm per kg. Solutions that have an osmolality greater than this are hyperosmolar and cause water to be drawn from the body into the stomach or gut to balance the osmolality. In athletes, water balance is already of critical importance, and hyperosmolar solutions may cut performance. Maltodextrins, at a given concentration, exert a much lower osmolality than simple sugars and can, therefore, be used at higher levels to provide more utilizable energy in an osmotically balanced formula.” For example, sports drinks can be formulated to contain 15% to 20% maltodextrin and still be at body osmolality, she says.
Most sports beverages promise a balance of caloric concentration and osmolality. “Drinks made with maltodextrins and corn syrup solids, with their widely varying osmolalities, permit flexible formulation while providing a highly pure, low-residue carbohydrate,” says Armstrong. “Fructose is often used to provide sweetness and also as a source of more slowly metabolized carbohydrate.” Maltodextrin is multifunctional. “In recovery beverages, maltodextrin helps smooth out high-protein solutions, enhancing mouthfeel and masking some of their off flavors,” she says.
A number of specialty carbohydrates are used in sports and energy drinks. “Isomaltulose is a natural sugar found in honey and sugar cane molasses as a disaccharide consisting of glucose and fructose,” says Debra Bryant, director, business development and technical services, BENEO-Palatinit Inc., Morris Plains, NJ. “It is produced in a biotechnical process and applied as a functional carbohydrate to capitalize on its distinctive nutritional and physiological properties.”
Isomaltulose is the only fully digestible low-glycemic carbohydrate that provides prolonged energy release in the form of glucose. “Isomaltulose supplies glucose as fuel for body and brain long after sucrose, high-fructose corn syrup or pure glucose have been digested and absorbed,” says Bryant. “It does this by being hydrolyzed and absorbed four to five times more slowly than sucrose, thanks to the strong binding of its glucose and fructose component. As a result, isomaltulose provides the same amount of carbohydrate energy as other sugars—4 calories per gram—but over a much-longer period, making it the perfect choice for endurance athletes or anyone committed to a serious, time-intensive exercise program.
“Furthermore, specific energy-release profiles can be achieved by combining isomaltulose with other carbohydrates,” continues Bryant. “Isomaltulose is about half as sweet as sucrose, while exhibiting the same balanced and natural taste profile as sucrose.”
Isomaltulose has also been shown to promote fat oxidation by increasing the use of body fat and fatty acids as energy sources. “When consumed as part of an exercise regimen, a sports drink containing this unique functional carbohydrate helps to improve the metabolism of fat,” says Bryant. “Isomaltulose causes a very distinct absorption that leads to the release of glucose energy at exactly the level where it triggers an increased rate of fat metabolization, while sparing glycogen in the liver and muscle. This leaves important glycogen reserves for when they are really needed.”
Isomaltulose is available in crystalline granule form and disperses in water, soy or a dairy base. “It is highly stable under acidic conditions, and its strong molecular bond translates directly into strong stability in sports beverages,” Bryant adds. “This, in turn, ensures that the drink’s osmolarity remains stable and vital from production all the way to actual consumption—whether the beverage is isotonic, hypertonic or hypotonic.
“Further,” continues Bryant, “our scientific studies show that a consumer energy drink containing 20 grams of isomaltulose will assure the provision of outstanding benefits, such as its steady and long-lasting energy supply in the form of glucose and its mild effect on blood glucose concentration, after consumption.”
D-ribose, a five-carbon carbohydrate, “is vital for the cellular synthesis of ATP (adenosine triphosphate), plus the genetic materials DNA and RNA,” says Kathy Lund, vice president, sales & marketing, ribose ingredient division, Bioenergy Life Science Inc., Ham Lake, MN. “It is widely used in beverages for energy enhancement, as it helps accelerate energy recovery in hearts and muscles, reduces fatigue and post-exercise malaise, and improves exercise performance over time.