Molecular formula: C12H24O11
Molecular weight: 344.31
Isomalt has fairly low water solubility, about 0.3 g per mL in water at room temperature.
Isomalt has a clean sweet taste. It iis about 40% as sweet as sucrose, on a weight basis. The concentration vs. response relationship in water is shown below (results in food systems will vary). This graph is based on data from DuBois, Walters, Schiffman, Warwick, Booth, Pecore, Gibes, Carr & Brands in "Sweeteners: Discovery, Molecular Design, and Chemoreception," D.E. Walters et al., Eds., American Chemical Society, 1991. The units of R are percent sucrose equivalent; the units of C are percent isomalt on a weight basis.
See my essay "Polyols--Digestive Issues" for a discussion of the potential gastrointestinal effects of polyol consumption.