Effects of heating and storage on hydroxy methylfurfural and diastase activity of different Turkish honeys

Samples were taken of Turkish honeys of different botanical origin, including Citrus (Citrus spp.), a high plateau mixture of Medicago sativa, Onobrychis sativa, astragalus globosus L., Echinops ritr L., Trifolium montanum L., Thymus vulgaris, and Verbascum densiflorum, cotton (Gossypium herbaceum), and pine (Pinus nigra) (honeydew honey). Samples were heated at 55, 65 and 75 degrees C for different heat exposure periods (15, 30,45,60 min). Honey samples were then left at room temperature (21 degrees C) for 9 months after which period the changes in diastase activity and hydroxyl methylfurfural (HMF) content were observed. Diastase number and HMF content of honey samples were significantly affected by heating, heat exposure period and storage time.