Physicochemical properties, composition and pollen spectrum of ling heather (Calluna vulgaris (L) Hull) honey produced in Spain

Abstract - The palynological and physicochemical properties of 28 samples of commercially produced Spanish ling heather honey were defined. On the basis of the melissopalynological analysis, 5 samples were excluded as they were of different botanical origin; 101 different pollen types were identified in the remaining samples. The relative richness of pollen from Calluna was between 10-33%. The high incidence of Erica spp pollen (usually > 10%), makes ling heather honey characterization difficult. The sugar spectrum showed low percentages of glucose (25.6 g/100 g), high levels of disaccharides, and traces of sucrose and trisaccharides. Enzymatic activity was higher (51.89 units on the Gothe scale) than that found in other unifloral Spanish honeys. The total acidity (45.5 meq/kg) exceeds the legal limit established for honey in the EEC. The mineral elements show a predominance of potassium, sodium and calcium. The different fluidity curves were determined using a 4-speed (16, 40, 80 and 160 rpm) concentric cylinder rotary viscometer. The thixotropical behaviour of this honey was determined as the crumbling index at the maximum tangential tension that could be generated by the viscometer used.