Botanical origin and characterization of monofloral honeys in Southwestern forest of Ethiopia

Abstract

The study was conducted to identify and characterize the monofloral honey types found in the Gesha-Sayilem forest. A total of 15 honey samples were collected during the honey flow seasons. For honey pollen analysis, the method recommended by the International Commission for Bee Botany and harmonized methods of the International Honey commission were used. Data were analyzed using one-way ANOVA, PCA, and Pearson correlation coefficients. Three monofloral honey types were identified, such as Schefflera abyssinica honey, Croton macrostachyus honey, and Vernonia amygdalina honey types. The mean moisture content of the honey samples of Vernonia amygdalina honey was 18.3 ± 1.02%, that for Schefflera abyssinica honey 18.1 ± 1%, and 21.2 ± 1.05% for Croton macrostachyus honey. The HMF value of the Vernonia honey ranged from 1.1 to 1.3 mg/kg, with a mean value of 1.2 ± 0.1 mg/kg; that of Schefflera abyssinica honey ranged from 2.2 to 2.5, with a mean value of HMF 2.3 ± 0.15; and that of Croton honey ranged from 2.4 to 2.6 mg/kg, mean value of 2.56 ± 0.15 mg/kg. There was a significant difference in the free acid content of honey samples due to the botanical origin of honey and sampling locations (p < .05). The electrical conductivity of honey samples in the Gesha-Sayilem forest was found within an international range, with a maximum limit of 0.8 mS/cm for most nectar honey. There was a significant strong correlation between proline, free acid, and sucrose. Moisture content was positively correlated with electric conductivity, due to the dependable nature of electrical conductivity on honey moisture. The study area honey meets the basic honey quality standards both of the national and international honey quality specifications, except that the moisture content of croton honey which was some what out of the accepted range.

Keywords: honey; honey quality; melissopalynology; monofloral honey.

FIGURE 1

Location map of Gesha and Sayilem districts (Addi et al., 2020)

FIGURE 2

PCA component plot in the function of floral origin of honey