Characterisation of VOC composition of Slovak monofloral honeys by GC×GC-TOF-MS

Abstract

Solid phase microextraction (SPME) followed by comprehensive two-dimensional gas chromatography coupled to a time-of-flight mass spectrometer (GC×GC-TOF-MS) was used to characterise volatile organic compounds in honeys of different botanical origins. Rape, sunflower, acacia, lime, raspberry, and phacelia honeys from Slovakia were studied in detail. Up to 900 compounds were detected at the given S/N ratio of 200. The poorest VOC profiles were found for acacia and rape honeys while lime honey showed the richest VOC composition. Approximately 100 compounds were present in all honeys studied, independently of their botanical origin. They belong to various chemical classes (hydrocarbons, alcohols, aldehydes and ketones, terpenes, benzene derivatives, and compounds containing heteroatoms). The compounds found in only one type of honey were also successfully identified.

Honey Volatiles as a Fingerprint for Botanical Origin—A Review on their Occurrence on Monofloral Honeys

“…Dimethyl disulfide was the most characteristic constituent detected in rape honeys produced in Denmark, France, Germany and Poland [52,71]. Besides this, there were several other compounds with variable presence depending on the honey origin: dimethyl trisulfide was observed for samples from Austria, Estonia and Germany, phenylacetic acid in samples from Estonia and Germany [41,105,125], both butyrolactone and pantolactone in Poland and Slovakia samples [70,71], benzyl alcohol in samples from Denmark, France, Germany and Poland [52,72], and benzoic acid in Estonia, Lithuania and Poland rape honey samples [55,72,105]. GC: Gas chromatography.…”

“…The described volatile compounds of linden tree honeys are included in all honeys obtained from different Tilia species, as these studies do not discriminate the species botanical source (Table 12). Monoterpene derivatives, namely rose oxides [71,75,103,114], p-methylacetophenone [52,71,75,85,103,111,114], carvacrol [41,69,71,75,85,103,111], p-cymene [41,70,71,85,103] and 8-p-menthen-1,2-diol [71,75] and α-terpinene [52,[69][70][71]85,103,111], were the compounds most frequently reported in the literature. Aromatic hydrocarbons, such as dimethyl styrene [57,70,71], were also common constituents in Tilia honeys.…”

“…Honey from acacia, characterized by a sweet, beeswax and sourish flavour [41], produced in thirteen countries from three continents, namely Europe, Africa and Asia, was studied, aiming at the identification of characteristic volatile compounds ( Table 2). The oxygen-containing monoterpene cis-linalool oxide, the alcohol 3-methyl-3-buten-1-ol and the aldehyde heptanal, detected in acacia honey samples from twelve of the thirteen countries [52,[68][69][70][71][72][73], were considered to be marker volatile compounds. cis-Linalool oxide was identified in honeys from Austria, Czech Republic, France, Germany, Italy, Morocco, Poland, Romania, Slovakia and Spain.…”

Optimization of the Extraction of the Volatile Fraction from Honey Samples by SPME-GC-MS, Experimental Design, and Multivariate Target Functions

“…The volatile profile is usually determined by HeadSpace Solid Phase Micro-Extraction (HS-SPME), followed by a gas chromatographic (GC) determination with Mass Spectrometry (MS) detection [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. HS-SPME GC-MS is quite widespread both as a fingerprinting tool [23][24][25][26] and for identification and quantification of specific classes of compounds or single analytes [27]: it is applied to honey samples in food safety and adulteration studies (for the determination of residues of chemicals used to combat honeybee diseases or parasite infestations, as fungicides, insecticides, acaricides, and pesticides [28]) or in authenticity studies for the determination of botanical biomarkers [29][30][31].…”

“…In the last years, increasing attention has been devoted to the characterization of the profile of volatile molecules in honey samples above all in authenticity and adulteration studies [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22], since the commercial value of honey is usually strictly correlated to its botanical and/or geographical origin. Unifloral honeys are certainly more valuable than multifloral; products show a different commercial value based on their botanical origin, particularly when the origin is strictly defined, for example, for PDO (Protected Designation of Origin) products.…”