Physicochemical and viscoelastic properties of honey from medicinal plants

Food Chemistry Volume 241, 15 February 2018, Pages 143-149 Food Chemistry Author links open overlay panelHuong Thi LanNguyenNaksitPanyoyaiVilia DarmaParamitaNitinMantriStefanKasapis School of Science, RMIT University, Bundoora Campus, Bundoora, Vic 3083, Melbourne, Australia Received 15 March 2017, Revised 30 June 2017, Accepted 21 August 2017, Available online 24 August 2017. https://doi.org/10.1016/j.foodchem.2017.08.070Get rights and content Highlights • Physicochemical and viscoelastic properties of honey from medicinal plants were studied. • WAXD peaks and DSC thermograms depend on fructose/glucose content in honey. • Thermomechanical measurements pinpoint the glass transition temperature of the honey matrix. Abstract The present work investigated the physicochemical and structural properties of Tulsi, Alfalfa and two varieties of Manuka honey derived from medicinal plants. Chemical analysis yielded data on the content of reducing sugars (glucose and fructose) that dominate the honey matrix, and of the minor constituents of protein, phenols and flavonoids. Standard chemical assays were used to develop a database of water content, electrical conductivity, pH, ash content, visual appearance and colour intensity. Physicochemical characteristics were related to structural behaviour of the four honey types, as recorded by small-deformation dynamic oscillation in shear, micro- and modulated differential scanning calorimetry, wide angle X-ray diffraction and infrared spectroscopy. The preponderance of hydrogen bonds in intermolecular associations amongst monosaccharides in honey yields a semi-amorphous or semi-crystalline system. That allowed prediction of the calorimetric and mechanical glass transition temperatures that demarcate the passage from liquid-like to solid-like consistency at subzero temperatures. Keywords Honey Physicochemical properties Viscoelastic behaviour Glass transition temperature