Isomalt is a sugar substitute, a type of sugar alcohol used primarily for its sugar-like physical properties. It has little to no impact on blood sugar levels, and does not stimulate the release of insulin. It also does not promote tooth decay, that is, it is tooth-friendly. Its energy value is 2 kcal per gram, 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. Isomalt may prove upsetting to the intestinal tract because it is incompletely absorbed in the small intestine, and when polyols pass into the large intestine, they can cause osmotically induced diarrhea and stimulate the gut flora, causing flatulence. As with dietary fibers, regular consumption of isomalt can lead to desensitisation, decreasing the risk of intestinal upset. Isomalt can be blended with high-intensity sweeteners such as sucralose, giving a mixture that has the same sweetness as sugar. Isomalt is an equimolar mixture of two mutually diastereomeric disaccharides, each composed of two sugars: glucose and mannitol and also glucose and sorbitol. Complete hydrolysis of isomalt yields glucose, sorbitol, and mannitol. It is an odorless, white, crystalline substance containing about 5% water of crystallisation. Isomalt has a minimal cooling effect, lower than many other sugar alcohols, in particular, xylitol and erythritol. Isomalt is manufactured in a two-stage process in which sucrose is first transformed into isomaltulose, a reducing disaccharide. The isomaltulose is then hydrogenated, using a Raney nickel catalyst. The final product — isomalt — is an equimolar composition of 6-O-α-D-glucopyranosido-D-sorbitol and 1-O-α-D-glucopyranosido-D-mannitol-dihydrate. Isomalt has been approved for use in the United States since 1990. It is also permitted for use in Australia, New Zealand, Canada, Mexico, Iran, the European Union, and other countries.
Uses
Isomalt is widely used for the production of sugar-free candy, especially hard-boiled candy, because it resists crystallization much better than the standard combinations of sucrose and corn syrup. It is used in sugar sculpture for the same reason.
