Isomalt is a sugar substitute, a type of sugar alcohol, used primarily for its sugar-like physical properties. It has only a small impact on blood sugar levels and does not promote tooth decay, i.e. is tooth-friendly. Its energy value is 2 kcal/g, half that of sugars. However, like most sugar alcohols, it carries a risk of gastric distress, including flatulence and diarrhea, when consumed in large quantities. Therefore, isomalt is advised to not be consumed in quantities larger than about 50 g per day for adults and 25 g for children. Isomalt may prove upsetting to the intestinal tract because the body treats it as a dietary fiber instead of as a simple carbohydrate. Therefore, like most fibers, it can increase bowel movements, passing through the bowel in virtually undigested form. As with other dietary fibers, regular consumption of isomalt might eventually lead one to become desensitized to it, decreasing the risk of intestinal upset. Isomalt is typically blended with a high-intensity sweetener such as sucralose, so that the mixture has about the sweetness of sugar.
Isomalt is an equimolar mixture of two disaccharides, each composed of two sugars: glucose and mannitol (α-D-glucopyranosido-1,6-mannitol) and also glucose and sorbitol (α-D-glucopyranosido-1,6-sorbitol). Complete hydrolysis of isomalt yields glucose (50%), sorbitol (25%), and mannitol (25%). It is an odorless, white, crystalline substance containing about 5% water of crystallisation. Isomalt has a minimal cooling effect (positive heat of solution), lower than many other sugar alcohols, in particular, xylitol and erythritol.
IMO is a multifunctional health molecule which exerts positive effects on human digestive health. There are numerous scientific papers available about the role of IMO as prebiotic, least flatulence (i.e., generating least gas), low Glycemic index, and Anti-caries Activities.
Prebiotics are defined as "non-digestible food ingredients that may beneficially affect the host by selectively stimulating the growth and/or activity of a limited number of bacteria in the colon". Many oligosaccharides are not digested in the small intestine and instead are fermented by Bifidobacterium species in the human colon, thus enhancing their proliferation. In this respect, fermentable oligosaccharides may be considered as prebiotics. Studies conducted to assess the digestibility of IMO mixtures indicates that the oligosaccharides are at least partially fermented by bacteria in the colon. Consequently, the un-hydrolyzed and, therefore, unabsorbed portion of an IMO mixture reaching the colon may stimulate the growth of bacterial subpopulations. There are number of published studies confirming the prebiotic effect of IMO including a recent one by the University of Alberta, Canada.
As excipient for the pharmaceutical industry isomalt can be used for powder blends and compression applications as well special ground grades for processing technologies such as wet granulation, roller compaction and fluid bed agglomeration. Its characteristics makes it suitable for various direct oral applications like tablets, capsule and sachet fillings. It shows compactibility, flowability and very low hygroscopicity. Also, it is physically and chemically extremely stable. Its sweet, well balanced taste is a decisive advantage for the formulation of direct oral applications, even in combination with active ingredients of unpleasant taste profiles. See also Polyols – pharmaceutical applications