DSC study of honey granulation stored at various temperatures

Abstract Non pasteurized, liquid and transparent honey containing very few and fine crystals was stored at 20, 10, 4 and −20°C. The crystal growth was analysed by differential scanning calorimetry (DSC) and by measuring the absorbance intensity at 660 nm over a 6 mth period. In honey stored at 20°C coarse crystals were formed with melting temperatures (Tm) between 45 and 65°C, whereas honey stored at −20°C granulated as a finely-grained, fondant-like honey, with Tm between 25 and 45°C. In honeys stored at 10 and 4°C big and small crystals were produced having intermediate characteristics when compared with honeys stored at 20 and −20°C. The rates of honey granulation were calculated from Δ H values at the four temperatures. A linear relationship was found between the enthalpy of melting (Δ H ) and the absorbance at 660 nm. The activation energy for the melting of coarse crystals was also determined with DSC.