Diastase and invertase activities in Meliponini and Trigonini honeys from Venezuela
Patricia Vit; Patrizio Pulcini
Twenty-seven stingless bee honeys from the west and south of Venezuela were examined for diastase (α- and ß-amylase) and invertase (α-glucosidase) activity. Diastase activity (g starch hydrolysed/100 g honey/h) was very low in Meliponini and Scaptotrigona spp. Honeys (2.6-3.5 diastase number), and much higher in other Trigonini honeys (6.6-35.6). Invertase activity (µmoles p-nitrophenyl glucopyranoside/kg honey/min) varied from 9.6 to 169.1 in Meliponini and from 15.9 to 214.3 in Trigonini honey, and was not statistically different in both groups. The correlation between diastase and invertase was very low, but both enzymes produced a dendrogram with two distinctive clusters for Meliponini and Trigonini honeys, excluding Scaptotrigona spp. The results suggest that the quality standards for stingless bee honeys will require a different approach for diastase activity. The use of diastase activity as an indicator of freshness, as is common practice for Apis mellifera honeys, is not applicable for Meliponini and Scaptotrigona spp. honeys, which are lacking in diastase.