The Influence of Thermal Treatment on the Concentration of HMF in Honey

Honey is sweet, thick, syrup like, aromatic, semifluid or crystallized substance produced by bees after processing the flower nectar or nectar of living plants or other secretions (honeydew). Some insects collect it as food, enrich their secretions and transmit it in the honeycomb cells that cover the wax caps, and so preserve it of absorption, moisture and decay. According to the chemical composition, honey is a natural product that contains natural antioxidants. Many plants synthesize phytochemical substances with antioxidant activity, which are very important for the defence of the human body of radicals. Collecting nectar from such plants bees transferred bioactive components in between. Dark honey is richer in content of antioxidants. Honey is a convenient base for the formation of 5-hydroxymethylfurfuraldehyde (HMF), as it contains high concentrations of saccharide (mainly hexoses), has a low pH value (containing organic acid) and a low water content. Fresh honey has a low content of HMF, almost equal to zero. However, its concentration increases when honey is heated and is in its storage. If you expose samples of honey at the temperature of 60°C for a longer period of time, a significant increase in the concentration of HMF is present. Noticeable increase of HMF concentration is observed by heating the samples at 90°C for 60 minutes where the results show that the average concentration of HMF was 48.8 mg/kg. Therefore, the content of HMF in honey is an important parameter in determining the quality of honey, his age, antioxidant activity, as well as the loss of its nutritional value.