Natural Sources of Isomalto-Oligosaccharides (IMO)
Isomalto-oligosaccharides (IMO) exist in very small quantities in a handful of natural foods, with the most notable sources being fermented products and honey. The concentration in these natural foods is significantly lower than in commercial products, making large-scale extraction economically unfeasible.
Fermented foods
Fermentation processes can create IMO as a byproduct of microbial activity. This occurs when microorganisms interact with starches in the food.
- Miso and soy sauce: These traditional Japanese condiments, made from fermented soybeans, contain small amounts of naturally occurring IMO.
- Sake: The fermentation of rice to produce this alcoholic beverage also results in trace amounts of IMO.
- Sourdough bread: Certain microbial fermentation in sourdough starter can generate small quantities of IMO.
- Kimchi: This fermented Korean vegetable dish contains low levels of IMO as a result of its fermentation process.
Sweeteners and other products
- Honey: The isomaltose component of IMO is a natural constituent of honey, though it is not technically classified as an IMO in isolation.
- Beer: Some brewing processes using specific microbial fermentation have been shown to produce small amounts of IMO.
Manufactured and Processed Foods Containing IMO
On a commercial scale, IMO is mass-produced enzymatically from starches like corn, tapioca, or peas and added to many processed products. Manufacturers favor IMO for its low-calorie content, moderate sweetness, and prebiotic fiber benefits.
Food products where IMO is commonly added
- Protein and nutrition bars: IMO is a prevalent ingredient in many low-carb or high-protein bars, where it serves as a binder, sweetener, and fiber source.
- Baked goods: Cakes, cookies, and pastries are formulated with IMO to reduce sugar content, add bulk, and improve texture.
- Beverages: Functional drinks, sweetened teas, and juices may include IMO for its sweetening properties and as a source of fiber.
- Dairy products: Low-sugar yogurts, ice creams, and other frozen dairy desserts use IMO to enhance texture and sweetness.
- Sweet sauces and syrups: As a functional sugar substitute, IMO is incorporated into condiments, relishes, sauces, and dessert toppings.
- Confectionery: Gummies, hard candies, and other sweets utilize IMO to lower calorie content without sacrificing sweetness.
Natural vs. Manufactured IMO: A Comparison
| Feature | Natural IMO Sources (e.g., honey, miso) | Manufactured IMO (e.g., VitaFiber™) |
|---|---|---|
| Concentration | Very low, trace amounts only | High concentration, often 90%+ pure IMO |
| Source | Byproduct of fermentation or naturally present compounds | Enzymatically produced from various starches (corn, tapioca, pea) |
| Economic Viability | Not viable for commercial extraction | Purpose-built for large-scale food manufacturing |
| Food Applications | Limited to specific fermented and raw products | Wide range of processed foods and supplements |
| Labeling | Not typically listed as an ingredient, just part of the product | Clearly listed as "isomalto-oligosaccharide" or a brand name |
| Processing | Created organically during food preparation | Requires multiple enzymatic steps and purification |
What to Know When Checking Food Labels
When looking for IMO in processed foods, the product label is the most important source of information. While some older products may have labeled IMO incorrectly or not at all, newer regulations often require clearer labeling. It's important to look for “isomalto-oligosaccharides” in the ingredient list, which often signals that a manufactured version has been added as a fiber or sweetener. This is particularly true for products marketed as low-sugar or high-fiber. The brand name VitaFiber™ is another common identifier for manufactured IMO.
Conclusion: Navigating IMO in Your Diet
While IMO can be found naturally in trace amounts within certain fermented foods and honey, the vast majority of isomalto-oligosaccharides consumed today are commercially manufactured and added to a broad range of processed foods. As a versatile ingredient, IMO serves as a low-calorie sweetener, prebiotic fiber, and bulking agent in everything from protein bars to ice cream. For consumers looking to identify foods with IMO, checking the ingredients list for “isomalto-oligosaccharide” is the most reliable method. Understanding the difference between natural and added sources can help you make informed decisions about the functional foods you incorporate into your diet. For additional information on specific food ingredient regulations, authoritative sources like the Food Standards Agency provide detailed reports.
