Volatile Compounds In Honey Research Articles

Development and validation of a high-throughput headspace solid-phase microextraction gas chromatography-mass spectrometry methodology for target and suspect determination of honey volatiles

The determination of volatile compounds is essential for the chemical characterisation of honey's aroma and its correlation to its sensory profile and botanical origin. The present study describes the development, optimization and validation of a new, simple and reliable method for the determination of volatile compounds in honey using headspace solid-phase microextraction combined with gas chromatography/mass spectrometry (HS-SPME-GC-MS). The optimization of the SPME conditions showed that the ratio of honey: water (2:1) and the incubation temperature (60 °C) are the most critical parameters. Gas chromatography was performed with medium polar Varian CP-Select 624 column and the experimental Retention Index for a number of compounds was determined as an additional identification feature for suspect analysis. The simultaneous use of four internal standards chlorobenzene, benzophenone, 2-pentanol and 4-methyl-2-pentanone and matrix matched calibration enhanced method accuracy achieving recoveries 73–114 % and repeatability ranging between 3.9 and 19 % relative standard deviations. Furthermore, the superiority of the HS-SPME to static head space technique was verified exhibiting four-to nine-fold higher sensitivity. Target and suspect screening were applied to 30 Greek honey samples and 53 volatile compounds belonging to different chemical classes, such as alkanes, aldehydes, ketones, alcohols, and esters were identified with quantified concentrations ranging between 3.1 μg kg−1 (Limonene) up to 20 mg kg−1 (Benzeneacetaldehyde). Among the new findings is the detection of Myrtenol in Greek pine honey and 2,3-butanediol in Greek oak honey. The developed analytical protocol can be a valuable tool in order to chemically characterize honey based on the volatile content.

Feasibility study for the use of colorimetric sensor arrays, NIR and FT-IR spectroscopy in the quantitative analysis of volatile components in honey

In this work, the feasibility of colorimetric sensor array (CSA), near-infrared (NIR), and Fourier transform infrared (FT-IR) spectroscopy (both individually and in combination) coupled with chemometrics for the quantitative analysis of volatile compounds (VCs) in honey were evaluated. The compounds were extracted using solid-phase microextraction and determined by gas chromatography-mass spectrometry. Nine calibration models were established with the intention of the quantitative analysis of the abundant VCs in honey samples. CSA showed the best predictive models for 2-furanmethanol (Rp = 0.873), benzyl alcohol (Rp = 0.959), phenyl ethyl alcohol (Rp = 0.959), furfural (Rp = 0.979), benzaldehyde (Rp = 0.906), 5-methyl furfural (Rp = 0.877), phenol, 2-methoxy- (Rp = 0.751) and 4-ketoisophorone (Rp = 0.986), while NIR showed the best model for 2-heptanone (Rp = 0.936). The results achieved with the NIR technique are superior to the ones obtained with FT-IR spectroscopy. Overall, the results demonstrated that combining CSA with NIR or FT-IR was feasible and could improve the prediction accuracy of VCs in honey.

Screening of volatile compounds in honey using a new sampling strategy combining multiple extraction temperatures in a single assay by HS-SPME–GC–MS

This paper proposes a new optimization strategy for the extraction of volatile compounds from honey samples using headspace solid-phase microextraction (HS-SPME) and separation/detection by gas chromatography–mass spectrometry (GC–MS). The new optimization strategy was based on the use of three different extraction temperatures in a single assay, aiming at extracting a high number of compounds with wide range of volatilities. As an analytical tool, experimental designs were used for the optimization. The variables extraction time (10–80min), extraction temperature (0–60°C), water volume (0.5–5mL) and percentage of sodium chloride saturation in water (0–100%) were optimised using a five-level fractional central composite design with CAR/DVB/PDMS fibre. The final optimised combination of extraction times at each temperature was 60min with the sample temperature being held at 60°C for 36min, 40°C for 18min and 0°C for 6min. The proposed method was compared to conventional methods which employ one or two extraction temperatures. It was found that the proposed method presented better results considering the response in terms of the arithmetic means of the peak areas. The use of multiple extraction temperatures for the HS-SPME procedure proved to be an excellent alternative for the screening of compounds present in honey with a wide range of volatilities.

Analysis of volatile compounds of Malaysian Tualang (<i>Koompassia excelsa</i>) honey using gas chromatography mass spectrometry

The constituents of honey's volatile compounds depend on the nectar source and differ depending on the place of origin. To date, the volatile constituents of Tualang honey have never been investigated. The objective of this study was to analyze the volatile compounds in local Malaysian Tualang honey. A continuous extraction of Tualang honey using five organic solvents was carried out starting from non-polar to polar solvents and the extracted samples were analysed using gas chromatography-mass spectrometry (GC-MS). Overall, 35 volatile compounds were detected. Hydrocarbons constitute 58.5% of the composition of Tualang honey. Other classes of chemical compounds detected included acids, aldehydes, alcohols, ketones, terpenes, furans and a miscellaneous group. Methanol yielded the highest number of extracted compounds such as acids and 5-(Hydroxymethyl) furfural (HMF). This is the first study to describe the volatile compounds in Tualang honey. The use of a simple one tube, stepwise, non-thermal liquid-liquid extraction of honey is a advantageous as it prevents sample loss. Further research to test the clinical benefits of these volatile compounds is recommended.

Volatile compounds in honey: a review on their involvement in aroma, botanical origin determination and potential biomedical activities.

Volatile organic compounds (VOCs) in honey are obtained from diverse biosynthetic pathways and extracted by using various methods associated with varying degrees of selectivity and effectiveness. These compounds are grouped into chemical categories such as aldehyde, ketone, acid, alcohol, hydrocarbon, norisoprenoids, terpenes and benzene compounds and their derivatives, furan and pyran derivatives. They represent a fingerprint of a specific honey and therefore could be used to differentiate between monofloral honeys from different floral sources, thus providing valuable information concerning the honey’s botanical and geographical origin. However, only plant derived compounds and their metabolites (terpenes, norisoprenoids and benzene compounds and their derivatives) must be employed to discriminate among floral origins of honey. Notwithstanding, many authors have reported different floral markers for honey of the same floral origin, consequently sensory analysis, in conjunction with analysis of VOCs could help to clear this ambiguity. Furthermore, VOCs influence honey’s aroma described as sweet, citrus, floral, almond, rancid, etc. Clearly, the contribution of a volatile compound to honey aroma is determined by its odor activity value. Elucidation of the aroma compounds along with floral origins of a particular honey can help to standardize its quality and avoid fraudulent labeling of the product. Although only present in low concentrations, VOCS could contribute to biomedical activities of honey, especially the antioxidant effect due to their natural radical scavenging potential.

Volatile Compounds in Honey Produced in the Central Valley of Ñuble Province, Chile

Headspace solid-phase microextraction (SPME) with an 85 µm Carboxen polydimethylsiloxane (CAR/PDMS) fiber was used to extract volatile compounds, and a gas chromatograph equipped with a mass spectometry detector (GCMS) was used to identify the volatile compounds in honeys. Thirty-four different volatile compounds from the headspace of honey produced in the central valley of Nuble Province, Chile, were extracted with fiber coating CAR/PDMS. The identified compounds were: 10 alcohols, 9 acids, 6 ketones, 3 aldehydes, 2 furans, 2 terpenes and 2 lactones. Only four of the volatile compounds had never been reported before as honey compounds; these being: 1,3-propanodiol, 2-methyl butanoic acid, 3,4-dimethyl-3-hexen-2-one, and 6-methyl-5-octen-2-one. These four compounds were found in three of the 10 analyzed samples. The compounds found in the highest percentage of area were ethanol, acetic acid, 1-hydroxy-2-propane, 3-hydroxy-2-butane, and furfural. However, the analyzed samples did not present a distinctive profile.

APPLICATION OF ELECTRONIC NOSE IN HONEY GEOGRAPHICAL ORIGINCHARACTERISATION

Honey volatile compounds were analysed by means of electronic nose, with the aim to capture honey aroma profile. 49 samples of black locust (Robinia pseudoacacia L.) and 16 of chestnut (Castanea sativa Mill.) honeys were analysed. Their botanical origin and physicochemical properties were analysed in accredited laboratory Geographical origin of samples has been known from interviews with beekeepers. Data obtained by electronic nose analysis were further analysed by principal component analysis (PCA) in order to determine differences among volatile profiles of samples with the same botanical origin but with different geographical origin. PCA result showed that honey samples from geographically close regions tend to group together, while those of distant geographical regions show differences though they are of the same botanical origin. Those results imply possibility to use electronic nose as a tool for honey geographical origin determination.

Study of the precision in the purge-and-trap–gas chromatography–mass spectrometry analysis of volatile compounds in honey

Data precision in the analysis by purge-and-trap coupled on-line to gas chromatography–mass spectrometry (P&T-GC–MS) of honey volatiles has been studied by statistical analysis. The contribution of non-random factors to dispersion of quantitative results was proven by comparing several statistical parameters (correlation coefficients, principal component analysis (PCA) eigenvalues and loadings) from both experimental and simulated data. PCA was also useful for grouping volatiles with similar dispersion behaviour; these groups being generally related to compounds with common properties or structural features. The use of area ratios improves data precision for compounds within the same group. Results from this study could be used for a better selection of internal standards in quantitative analysis of volatiles by P&T-GC–MS.

Absorption of volatile compounds in honey from stored spices

SUMMARYSpices and coffee stored in food containers result in detectable volatile compounds in honey subsequently stored in these containers. These ‘off-flavours’ are bound to the plastic lining inside the lid and later contaminate the honey. The kind, number and concentration of these compounds depend on what has been stored in the container. Honeydew honey was used in this study. Tea did not affect the aromatic profile of honey, whereas coffee resulted in one volatile compound in honey, peppermint two, sage three, cinnamon four, oregano eight, and basil and cinnamon nine. In this study we used the purge and trap gas chromatographer/mass spectrometer system to identify the volatile compounds, as well as human sensory tests to evaluate the ability of the consumer to perceive off-flavours in honey.

Analysis of volatile composition of honey by solid phase microextraction and gas chromatography‐mass spectrometry

AbstractHoney aroma is largely dependent on its volatile fraction, which in turn is influenced by nectar composition and by possible modifications after harvesting. Solid phase microextraction (SPME) allows a simple and rapid fractionation of volatile compounds in honey as a prior step to their GC‐MS qualitative and quantitative determination. A simple SPME‐based procedure has been developed for GC‐MS analysis of honey volatiles and applied to the study of 6 different commercial honeys. The possibility of honey characterization from the analytical data obtained by the SPME method is discussed.