Volatile fraction of commercial thyme honeys produced in Mediterranean regions and key volatile compounds for geographical discrimination: A chemometric approach

Abstract

The aim of the present study was to investigate the volatile fraction and discriminate 34 commercial thyme honeys from Morocco, Egypt, Spain, and Greece according to geographical origin, using key volatile compounds in combination with chemometrics. Sixty-two volatile compounds belonging to different classes were identified and semi-quantified using headspace solid phase micro-extraction coupled to gas chromatography/mass spectrometry (HS-SPME-GC/MS). Applying chemometric analyses to 17 volatiles (p < 0.05), honeys were successfully discriminated according to geographical origin. Correct classification rate was 88.2% using the cross-validation method. Volatile compounds proved to be a powerful tool for discriminating commercial thyme honeys from different countries.

The Honey Volatile Code: A Collective Study and Extended Version

“…The aforementioned compounds comprise isoleucine- and leucine-derived volatiles and are found in a wide range of foods such as honey, beer, cheese, coffee, chicken, fish, chocolate, olive oil, and tea. These volatile compounds are associated with a fruity and malty flavor [21,22].…”

“…Eucalyptus honeys were characterized by the presence of heptane and beta -damascenone, since these compounds were found in higher amounts (mg/kg). The presence of hydrocarbons in honey is a typical phenomenon, whereas beta -damascenone is a cyclic carotenoid derivative and possesses a rose odor [22].…”

“…Fir honeys had higher amounts (mg/kg) of nonanal, decanal, hexanoic acid ethyl ester, heptanoic acid ethyl ester, octanoic acid ethyl ester, nonanoic acid ethyl ester, decanoic acid ethyl ester, dodecanoic acid ethyl ester, tetradecanoic acid ethyl ester, nonane, 5-methyl-4-nonene, 6-methyl-5-hepten-2-one, geranyl acetone, 1-2-(furanyl)-ethanone, alpha -isophorone, 4-ketoisophorone, and 2-hydroxyisophorone. The volatile compounds 6-methyl-5-hepten-2-one and geranyl acetone comprise open-chain carotenoid-derived volatiles, whereas the isophorone related compounds belong to the class of norisoprenoids, resulting from the degradation of terpenoids [22]. Geranyl acetone and 6-methyl-5-hepten-2-one possess a strong floral, green and fruit-like odor.…”

Headspace Solid Phase Microextraction Coupled to GC/MS for the Analysis of Volatiles of Honeys from Arid and Mediterranean Areas of Algeria

“…Several studies were carried out using different statistical analyses (chemometrics) to find volatile compounds that could be used to distinguish the floral or geographical origin of honey. [32,33] In this work, the Ascending Hierarchical Classification (AHC) was used to determine the influence of extraction conditions on the classification of honey regions (Figure 4 and Table 2). The classification was based on the peak areas of ten major components for each applied parameter.…”

Geographical discrimination of Chinese winter wheat using volatile compound analysis by HS‐SPME/GC‐MS coupled with multivariate statistical analysis

“…For instance, the isotope ratio mass spectrometry technique, multielement analysis, phenolic compounds by high‐performance liquid chromatography‐mass spectrometry (MS), and near‐infrared fingerprints have been applied to discriminate geographical origin of wheat, rice, fruits, and almond; however, separation techniques such as liquid and GC coupled with MS attained great attention in recent years for authentication studies and now become a widely adopted method for geographical traceability. Recently, various agricultural products have been successfully discriminated through GC profile such as wine, rice, extra virgin olive oil, honey, and tea …”