Isomalt is a sugar substitute and a sugar alcohol made from beets. Despite its natural origins, the compound is generally considered artificial, at least in so far as it has been extensively chemically manipulated. It is most commonly used in commercial food manufacturing, and items that contain it can be labeled “sugar free.” It has also been shown to extend the shelf-life of certain products, which has led to its widespread use as a preservative.
Creation and Production
The compound was first engineered by the German company BENEO-Palatinit in the early 1980s. It became popular throughout Europe at that time, but was not approved for use in the United States until 1990. Most countries around the world have also approved it for human consumption, and it remains a popular additive to a number of foods, particularly sweets.
Creating isomalt is somewhat complicated. Chemists first isolate the natural sugar compounds from beets, then convert them — usually with heat — into a reducing disaccharide. This product is then hydrogenated using a catalytic converter. The end result is a sugar-like substance that has many of the characteristics of a natural sweetener but contains only low levels of glucose. Accordingly, it has only a very minor impact on blood sugar levels, and is generally considered “safe” for diabetics and others with blood sugar concerns. Isomalt is also gluten free.
The compound has a much more complex chemical composition than does natural sugar. Its official molecular formula is C12H24O11, and it is a bonding of two independent disaccharides with a crystalline structure.
Uses as a Sweetener
By far the most common use of isomalt is as a sweetener in “sugar free” candies, cough drops, and other commercially-prepared foods. Food manufactures can often achieve the same sweetness with the compound as they could with sugar, but without the blood sugar and caloric concerns. This is not to say that the substitute is completely without calories — it contains roughly half the calories of sugar. As a result, it's not used in zero calorie products. It doesn't cause tooth decay in the way that regular sugar does, though, and some toothpastes use it to improve taste without promoting cavities.
It is sometimes blended with other non-sugar sweeteners like sucralose to give it approximately the same sweetness as sugar, though it does not bake or react as sugar would. It does not caramelize as quickly, for example, nor does it look or taste quite the same. Some forms that are sold for baking are actually quite bitter. The compound is often treated with a chemical known as acesulfame potassium to granulate it, which can give it an undesirable taste when consumed on its own.
Uses as a Preservative
The substance has also been shown to prolong shelf life and is sometimes used in breakfast cereals, crackers, and bakery products like breads and muffins. It tends to stabilize other ingredients, and can stave off mold and spoilage; it may also help keep dry goods fresh and crisp for longer.
Many chefs and professional food decorators use isomalt for aesthetic purposes. It is very popular in cake garnishes and food molds — most of the confections made for television competitions, wedding shows, and other public displays use the substitute because of how glossy it looks and how quickly it sets up. It is highly resistant to humidity, and is typically very easy to work with and mold.
Digestive Concerns and Stomach Upset
Excessive consumption of isomalt-containing foods can lead to serious stomach upset, bloating, and gas. A number of people also report these symptoms even after minimal exposure. In most cases, this is because the compound is not easily digestible. While the human body typically treats regular sugars as carbohydrates, it considers isomalt a fiber.
Consumption tends to increase bowel movements and can also cause painful bloating, diaherra, and flatulence. To minimize these negative effects, most medical professionals recommend that people limit their daily intake to about 1.7 ounces (50g) for adults, and about 0.88 ounces (25g) for children. Some studies have also suggested that eating small amounts of isomalt over time can build up a slow tolerance.