A Survey of Commercially Available Isomaltooligosaccharide-Based Food Ingredients

Isomaltooligosaccharides (IMOs) are included in many commercially available food products including protein/fiber bars, shakes, and other dietary supplements. Marketed as "high fiber," "prebiotic soluble fiber," and/or as a "low-calorie, low glycemic sweetener," IMO may be present in significant amounts, for example, more than 15 g/item or serving. Herein, high-pressure anion exchange chromatography with pulsed amperometric detection and high-pressure liquid chromatography with differential refractive index detection are used to compare 7 commercially available IMO-containing bulk food ingredients. The ingredients are typical of those produced either (a) via bacterial fermentation ("fermented" IMO or MIMO) of sucrose in the presence of a maltose acceptor mediated by a glucosyltransferase enzyme (dextransucrase), or (b) via transglycosylation of hydrolyzed starch with α-glucosidase ("industrial" IMO). Analysis of the results with respect to digestibility suggests that the potential glycemic impact of the ingredients and products containing "industrial" IMO may be inconsistent with the product labeling and/or certificates of analysis with respect to overall fiber content, prebiotic fiber content, and glycemic response and are thus inappropriate for diabetic patients and those on low-carbohydrate (for example, ketogenic) diets.