Physicochemical and Sensory Evaluation of Romanian Monofloral Honeys from Different Supply Chains

Abstract

Honey quality and authenticity are influenced by floral origin, processing, and storage, with implications for composition and sensory appeal. This study offers a comparative assessment of eight monofloral honey samples, representing five botanical varieties: acacia, linden, rapeseed, lavender, and thyme. For acacia, linden, and rapeseed, both producer-sourced and commercial honeys were analyzed, while lavender and thyme samples were available only from local beekeepers. The botanical origin of each sample was confirmed using morphological markers of pollen grains. Physicochemical characterization included acidity, pH, moisture content, refractive index, hydroxymethyl furfural (HMF), proline concentration, and carbohydrate profiling by HPLC-RID. Acacia honey exhibited the lowest acidity and HMF levels, alongside the highest fructose/glucose (F/G) ratios, indicating superior freshness, lower crystallization risk, and a sweeter flavor profile. In contrast, rapeseed honey showed elevated glucose levels and the lowest F/G ratio, confirming its tendency to crystallize rapidly. All samples recorded proline concentrations well above the quality threshold (180 mg/kg), supporting their authenticity and proper maturation. The estimated glycemic index (eGI) varied between 43.91 and 62.68 and was strongly inversely correlated with the F/G ratio (r = -0.98, p < 0.001). Sensory evaluation highlighted acacia honey from producers as the most appreciated across visual, tactile, and flavor attributes. Correlation analyses further revealed consistent links between sugar composition and both physical and sensory properties. Overall, the findings reinforce the value of integrated analytical and sensory profiling in assessing honey quality and authenticity.

Keywords: floral origin; honey; palynological analysis; physicochemical parameters; sensory evaluation; sugar profile.

Figure 1

Microscopic images of pollen sediment from monofloral honey samples: (a) AH_P, producer acacia honey; (b) AH_C, commercial acacia honey; (c) RH_P, producer rapeseed honey; (d) RH_C, commercial rapeseed honey; (e) TLH_P, producer linden honey; (f)—TLH_P, commercial linden honey; (g) LH_P, producer lavender honey; (h) TH_P, producer thyme honey.

Figure 2

HMF content in honey samples. Results presented as means ± SD (n = 3). ^a–f—different lowercase letters indicate significant differences between samples (p < 0.05) according to Turkey’s multiple comparison test. Samples sharing same letter are not significantly different from each other; AH_P, producer acacia honey; AH_C, commercial acacia honey; RH_P, producer rapeseed honey; RH_C, commercial rapeseed honey; TLH_P, producer linden honey; TLH_P, commercial linden honey; LH_P, producer lavender honey; TH_P, producer thyme honey.

Figure 3

Chromatogram of producer acacia honey.

Figure 4

The estimated glycemic index (eGI) values. AH_P, producer acacia honey; AH_C, commercial acacia honey; RH_P, producer rapeseed honey; RH_C, commercial rapeseed honey; TLH_P, producer linden honey; TLH_P, commercial linden honey; LH_P, producer lavender honey; TH_P, producer thyme honey.

Figure 5

The correlation between the honey samples’ estimated glycemic index and fructose/glucose ratio.

Figure 6

The proline content (mg/kg) of the honey samples. The results are presented as the means ± SD (n = 3). ^a–g—the different lowercase letters indicate significant differences between the samples (p < 0.05) according to Turkey’s multiple comparison test. Samples sharing the same letter are not significantly different from each other. AH_P, producer acacia honey; AH_C, commercial acacia honey; RH_P, producer rapeseed honey; RH_C, commercial rapeseed honey; TLH_P, producer linden honey; TLH_P, commercial linden honey; LH_P, producer lavender honey; TH_P, producer thyme honey.

Figure 7

Sensory perception of monofloral honey samples by untrained panelists: (a) visual and tactile characteristics; (b) gustatory and olfactory characteristics. AH_P, producer acacia honey; AH_C, commercial acacia honey; RH_P, producer rapeseed honey; RH_C, commercial rapeseed honey; TLH_P, producer linden honey; TLH_P, commercial linden honey; LH_P, producer lavender honey; TH_P, producer thyme honey.

Figure 8

Correlation matrix of physicochemical and sugar parameters in honey samples.Significance levels: * p < 0.05; ** p < 0.01; *** p < 0.001.

Figure 9

Kendall’s Tau correlations between (a) visual and tactile characteristics and physicochemical properties of honey samples; (b) flavor and taste characteristics and physicochemical properties of honey samples.Significance levels: * p < 0.05; *** p < 0.001.