Unlocking Phacelia tanacetifolia Benth. honey characterization through melissopalynological analysis, color determination and volatiles chemical profiling

Abstract

Phacelia tanacetifolia Benth. honey (14 samples) collected in Poland was characterized by melissopalynological analysis, color determination (CIE L*a*b*C_ab*h_ab° coordinates) and volatiles (VOCs) composition. VOCs were isolated by headspace solid-phase microextraction (HS-SPME, two fibers) and ultrasound-assisted solvent extraction (USE, two solvents) and analyzed by GC-MS. Principal component analysis (PCA) and hierarchical-tree clustering (HTC) were applied to show trends and form groups and to indicate the most representative unifloral samples. Six samples were pointed out with average pollen 74.9% and color parameters (L=85.1; a*=-0.8; b*=27.9; C_ab*=27.9; h_ab*=91.9) that were significantly correlated. High abundance of trans-linalool oxide (27.3-45.9%) that was significantly correlated with the pollen percentages, hexan-1-ol (4.4-5.7%) and lavender lactone (0.8% - 1.5%) were characteristic for their headspace. C₁₃-norisoprenoids, mainly (E)-/(Z)-3-oxo-retro-α-ionol (4.7-5.4%; 6.9-9.4%) and vomifoliol (9.0-13.0%) dominated in their USE extracts.

Keywords: C(13)-norisoprenoids; CIE L*a*b*C(ab)*h(ab)° color coordinates; Lavender lactone; Pollen analysis; Unifloral phacelia honey; trans-Linalool oxide.