What Is Hydroxymethylfurfural?

The decomposition of sugars produces the organic compound hydroxymethylfurfural, also known as HMF. Dehydrated or heat-treated foods typically contain the substance in varying amounts. The chemical affects color and taste, and manufacturers monitor levels in some foods, including honey. Some speculate that the compound has a deleterious effect on bee colonies, though medical researchers have seen that it may be useful in cases of sickle cell anemia.

The chemical compound hydroxymethylfurfural contains a furan ring comprised of alcohol and aldehyde groups. HMF occurs as a product of decomposing sugars that include dextrose, glucose and sucrose. Sugar decomposition typically takes place in the presence of acid and may occur naturally, over time, or through heat exposure. HMF production increases with extended shelf life and/or heat exposure. Foods exposed to temperatures of 86 degrees Fahrenheit (30 degrees Celsius) for six months usually contain the same amount of HMF as foods exposed to 158 degrees Fahrenheit (70 degrees Celsius) for five minutes and immediately cooled.

Many processed foods including coffee, dehydrated fruits, juices, and milk contain HMF. Coffee averages anywhere from 300 to 2900 milligrams/kilogram (mg/kg), while prunes typically contain 2200 mg/kg. Hydroxymethylfurfural formation produces flavors ranging from buttery to caramel and produces varying degrees of caramel color.

As hydroxymethylfurfural affects color and flavor, certain industries measure and monitor the chemical’s presence in foods. Distilled alcohol producers use hydroxymethylfurfural levels in making brandy, rum, and whiskey. Depending on the desired color and flavor of the finished product, manufacturers ensure adequate HMF levels by adding acids, alkalis, or salts during the distillation process or by pouring the liquid into toasted barrels.

Food regulatory agencies in the United Kingdom limit HMF levels of honey brought into or manufactured in the country to 40 mg/kg. In Japan, these levels must not exceed 5 mg/kg. These levels allow leeway for processing and future shelf life, as any product containing HMF levels of 100 mg/kg or more are considered to be of substandard quality.

Some researchers believe the hydroxymethylfurfural levels found in high fructose corn syrup may be a contributing factor to the higher mortality rates, known as colony collapse disorder, noticed by beekeepers. High fructose corn syrup contains on average 20 mg/kg of HMF and may be causing the early demise of bee populations. Beekeepers often use the substance to supplement nectar shortages or to enhance overall honey production.

The chemical, in rare instances, has unusual health benefits. An abnormal form of hemoglobin, known as hemoglobin S produces a sickle shape in red blood cells, especially under low oxygen conditions. Scientists fed laboratory animals HMF and noted that the chemical entered red blood cells and bound with hemoglobin S. This reaction maintained intracellular oxygen levels and inhibited sickle cell shaping without modifying other aspects of the cell.