Palynological studies and application of response surface methodology to establish the quality attributes in Eucalyptus honey

In this study honey samples of Eucalyptus honey (Eucalyptus lanceolatus) were botanically characterized. Response surface methodology was used to analyze the effect of temperature, time and PH on the quality responses (hydroxymethylfurfural concentration and diastatic activity) of Eucalyptus honey. A central-composite rotatable design was used to develop models for the responses. At the central value of time (10 min), the maximum concentration of hydroxymethylfurfural was demonstrated at the highest temperature and PH. The maximum value of hydroxymethylfurfural concentration was also obtained at the maximum time and temperature, while keeping the PH at the central value of 5.3. Diastatic activity decreased as the PH moved away from the central pH value of 5.3 to 5.6 at any level of temperature and time. Three-dimensional response surfaces were superimposed, and the overlapping regions gave the diastatic activity (calculated as diastase number 9 to 23.09 degrees G) and hydroxymethylfurfural concentration (3 to 10.21 mg kg(-1)) at 48 1 degrees C for 9.5 +/- 1 min at 5.15 +/- 0.15 PH.