Honey Aroma Research Articles

Volatile metabolites or pollen characteristics as regional markers of monofloral thyme honey?

AbstractThirty‐one monofloral thyme honeys were collected from professional beekeepers from four different regions in Greece during harvesting year 2012–2013. Aqueous solutions of honeys were subjected to headspace solid‐phase microextraction coupled to gas chromatography with mass spectrometry to record complete volatile pattern, whereas pollen screening was accomplished using the melissopalynological analysis. The primary objective was to investigate the volatile pattern and whether specific volatile metabolites or pollen grain percentages could serve as regional markers. Results showed that 37 volatile compounds, belonging to different classes, were identified and semi‐quantified, using the internal standard method. Application of multivariate analysis showed that ten volatile metabolites recorded significant variations (p<0.05) according to geographical origin of thyme honey. Linear discriminant analysis classified honeys according to geographical origin providing a classification rate of 92.3% using the cross validation method based on the statistically significant volatile metabolites. This was not the case for the overall correct classification rate based on pollen grain percentages which was only 51.6%. Volatile compounds analysis, apart from the specific information on the development of monofloral thyme honey aroma, proved to be a fast and more accurate tool for its discrimination according to production area, compared to melissopalynology.

ASSESSMENT OF THE GENUS DECORATIVE BUDDLEJA L. IN THE TERMS OF RIGHT-BANK FOREST-STEPPE OF UKRAINE

The range of woody plants plays a significant role within shrubs. They value above all as they easily draw the area that immediately makes necessary volume. In addition, the widespread use of shrubs in landscaping will reduce the number of tree seedlings, their growing is quite time consuming and worthwhile. Very important is the fact that shrubs compared to trees are more resistant to adverse environmental factors and better acclimatized after transplantation. There are about 125 species of Buddleja L. of well-flowering shrubs which are common in tropical, subtropical and temperate latitudes parts of Asia, Africa, North and South America. This type is very attractive for decorative gardening due to late and long flowering (June to October). The attractiveness of plants during flowering period supplementes sustainable honey aroma. Therefore it is of great importance in determining the decorative qualities of the genus Buddleja L. in the conditions of Right-Bank Forest-Steppe Ukraine. Decorative rating studied species and varieties of the genus Buddleja L. Is conducted by the method of O. Kalinichenko. We have studied objects of praised decoration. During the growing season 2014 species and varieties of the genus Buddleja L. received average annual estimate – 3.5 2015 – 4.2016 – 3.7. The results suggest that ornamental plants as clear, they are well allocated on the general background of space. During flowering period of the objects (VI-IX) score highest decoration – 5 points, that is as decorative plants provide great attractiveness, causing the observer strong emotional feeling of admiration. Visual assessment decorative species of Buddleja L. conducted by the method О. V. Horoshih and O. G. Horoshih. According to the results of the studied species and varieties of the genus Buddleja praised architectonics (B. davidii and its sorts – 8 points, B. аlternifolia – 9 points) and decorative (B. davidii and its sorts – 29 points, B. аlternifolia – 30 points). For a comprehensive assessment of all studied plants are highly decorative. Species of Buddleja L. is quite promising in ornamental horticulture. Thus, the genus Buddleja L. is quite promising for use in ornamental horticulture and gardening, so the study species and varieties of this kind are important for enriching and improving the range of flowers and ornamental plants.

Study on Honey Quality Evaluation and Detection of Adulteration by Analysis of Volatile Compounds

Abstract Fast evaluation of honey quality is a topical and significant problem of the food industry, bee keepers and consumers. In this work, 22 samples of commercially available honey aromas (with methyl and ethyl esters of phenylacetic acid predominated), 13 samples of authentic honey collected directly from bee keepers (characterised by high content of benzaldehyde, 2-phenylethanol, hotrienol and 2-phenylacetaldehyde) and 63 honeys purchased from an outdoor market were evaluated based on volatiles profiles determined through solid-phase microextraction coupled with gas chromatography-mass spectrometry (SPME-GC/MS) and then suspicious samples were identified. The results were statistically processed and compared with results of a sensory analysis. Six honeys, which differed significantly in volatiles profiles (outliers detected by Factor Analysis), selected volatile substance representation (furan-2-carbaldehyde, 1,4-dimethylpyrazole, benzaldehyde, 2-phenylacetaldehyde) and honey aroma intensity and pleasantness were subjected to targeted analyses (i.e. determination of 5-(hydroxymethyl)-2-furaldehyde, diastase activity, unauthorized additive presence). Four of these suspicious samples were found to have high content of 5-(hydroxymethyl)-2-furaldehyde (more than 40 mg/kg), three honeys had low values for diastase activity (less than 8) and three samples positive for triacetin addition. The fact that all these samples revealed a breach of least one of the selected quality parameters defined by the Codex Alimentarius standard proved the proposed methodology to be a useful tool for fast quality evaluation of honey.

Natural Flavor Additives Influence the Sensory Perception and Consumer Liking of Australian Chardonnay and Shiraz Wines

The use of winemaking additives is governed by strict regulations, and currently, flavor additives are not legally permitted in commercial wine production: their addition to a wine renders it a “wine product.” However, Australian wine consumers have previously indicated their acceptance of the use of flavorings in wine. Consumers were found to be significantly more accepting of natural flavorings than of many additives currently used in winemaking (e.g., acid, tannins, oak chips). In this study, we investigated the potential for flavorings to enhance wine aroma and flavor and explored consumer liking of flavored wines. Four inexpensive commercial wines (two Chardonnay and two Shiraz) were flavored with natural additives to enhance aroma and flavor. Descriptive analysis (DA) was performed to determine the sensory profiles of control and flavored wines. Overall, the addition of flavor additives significantly increased the intensity of key attributes (e.g., citrus aroma and honey flavor) and decreased undesirable attributes (e.g., green, earthy notes) in wines. Following DA, consumer tastings (n = 218) were conducted to assess liking of control versus flavored wines. Based on individual liking scores, three hedonic clusters were identified. For Chardonnay, Cluster 1 (C1) liking was driven by passion fruit aroma, C2 by oak flavor and stone fruit and honey aromas, and C3 by butter aroma, honey flavor, and fruit and phenolic length. Drivers for Shiraz included chocolate flavor and red fruit and confectionary aromas for C1, oak flavor and red berry and green aromas for C2, and oak aroma and flavor and red fruit and confectionary aromas for C3. Findings suggest flavorings can enhance wine sensory properties, and for some consumer segments, wine acceptability (or liking).

If Bees Are Few: A Hive of Bee Poems ed. by James Lenfestey

Reviewed by: If Bees Are Few: A Hive of Bee Poems ed. by James Lenfestey Jeremy Caldwell (bio) James Lenfestey, editor. If Bees Are Few: A Hive of Bee Poems. University of Minnesota Press. If Bees Are Few is an anthology spanning 2,500 years “from Sappho to Sherman Alexie,” as its cover copy suggests. Edited by James Lenfestey, it is as eclectic in its selection as it is vast in its time frame. The book takes its title from Emily Dickinson, who was herself fascinated with bees, and comes as a poignant reminder that bee populations are dwindling, hives are collapsing, and the effects may be devastating if bees indeed become few. In the first poem, Sherman Alexie candidly lays out the dangerous consequence from the eyes of the beekeeper: “The bees are gone. / We need new bees / Or we are fucked.” Bees have captivated the popular imagination in recent years, thanks to a plethora of documentaries and the work of grassroots organizations like the Honeybee Conservancy. Following a decade’s sharp decline in bee populations—nearly a third of all bee colonies in the United States—this book is a call to bring the bee into the literary world and into our broader consciousness. As Lenfestey notes in the introduction, “poets do what we can, in our reverie, our observation, our listening, our metaphors, our occasional beekeeping, our outrage, our grief, to keep the sweetness and sting of these poetic companions alive.” This flexibility and malleability of the image of bees lends itself well to the anthology’s range. As Bill McKibben writes in the foreword, bees are a metaphor “for so many things.” The book brings awareness, but it does so with range and depth. The variety of poets mirrors our interactions with bees as well as the roles they play in our lives. Some poems are principally about bees, such as Thomas R. Smith’s, “The Queen in Winter,” a solemn ode to the bumblebee queen’s lonely journey through the winter months. But an equal number of poems see bees as simply part of the scenery, the everyday workings of life, an inseparable, if not particularly visible, part of our houses, our gardens, the words we write, and, as Rumi points out, even to our own bodies: We are bees,and our body is a honeycomb.We madethe body, cell by cell we made it. [End Page 178] These poems tackle the complexity of the human-bee relationship, from our enjoyment of the sweet aroma of amber-hued honey to possible rage after encountering the unlucky end of a bee and its sting, as does Diane Lockward: And tomorrow may you rest on my tableas I peruse the paper. May you shakebeneath the scarred face of a serial killer.May you be crushed by the morning news. The buzzing never stops, as poets from Rumi to Emerson and Issa to Whitman deliver their odes and rants in this anthology, which is marked to donate a portion of the proceeds from sales to the University of Minnesota’s Bee Lab, in hopes of heading off the regret Lucille Clifton captures in “earth”: what was called treeit bore varicoloredleaves children beesall this used to be aplace once all thiswas a nice place once Jeremy Caldwell Jeremy Caldwell is an ma student in creative writing at the University of Nebraska-Lincoln. He lives in Lincoln, NE. Copyright © 2017 University of Nebraska Press

Comparison of Fermentation and Wines Produced by Inoculation of Hanseniaspora vineae and Saccharomyces cerevisiae.

Interest in the use of non-Saccharomyces yeasts in winemaking has been increasing due to their positive contributions to wine quality. The non-Saccharomyces yeast Hanseniaspora vineae is an apiculate yeast that has been associated with the production of wine with good aromatic properties. However, little is known about the fermentation dynamics of H. vineae in natural must and its interaction with autochthonous yeasts. In the present study, we performed semi industrial fermentations of Macabeo and Merlot musts inoculated with either H. vineae or S. cerevisiae. The yeast population dynamics were monitored by plate culturing, PCR-DGGE and massive sequencing techniques. The results obtained with these techniques show that H. vineae was able dominate the autochthonous microbiota in Macabeo must but not in Merlot must, which exhibited a larger, more diverse yeast population. The presence of H. vineae throughout most of the Macabeo fermentation resulted in more fruity and flowery wine, as indicated by the chemical analysis of the final wines, which demonstrated a strong presence of phenyl ethyl acetate at concentrations higher than the threshold of perception and approximately 50 times more than that produced in wines fermented with S. cerevisiae. This compound is associated with fruity, floral and honey aromas.

Discrimination of honeys using colorimetric sensor arrays, sensory analysis and gas chromatography techniques

Aroma profiles of six honey varieties of different botanical origins were investigated using colorimetric sensor array, gas chromatography–mass spectrometry (GC–MS) and descriptive sensory analysis. Fifty-eight aroma compounds were identified, including 2 norisoprenoids, 5 hydrocarbons, 4 terpenes, 6 phenols, 7 ketones, 9 acids, 12 aldehydes and 13 alcohols. Twenty abundant or active compounds were chosen as key compounds to characterize honey aroma. Discrimination of the honeys was subsequently implemented using multivariate analysis, including hierarchical clustering analysis (HCA) and principal component analysis (PCA). Honeys of the same botanical origin were grouped together in the PCA score plot and HCA dendrogram. SPME-GC/MS and colorimetric sensor array were able to discriminate the honeys effectively with the advantages of being rapid, simple and low-cost. Moreover, partial least squares regression (PLSR) was applied to indicate the relationship between sensory descriptors and aroma compounds.

Enzymatic browning reduction in white cabbage (Brassica oleracea) using honey: Does honey color matter?

Thirteen honey groups consisting of 66 samples from different geographic locations in Zambia were screened for total phenolics, total flavonoids and antioxidant activity, and their color parameters (L*, a* and b*) were measured by transmittance. Total phenolic and flavonoid contents ranged from 479.2 ± 1.1 to 1383.9 ± 3.7 mg Gallic Acid Equivalents per kilogram of honey (mg GAE/kg) and from 85.5 ± 1.8 to 609.2 ± 3.7 mg Catechin Equivalents per kilogram of honey (mg CE/kg) respectively while total antioxidant activity ranged from 3.9 ± 0.5 to 7.8 ± 0.9 mmol (Fe2+)/kg. Enzymatic browning reductions increased with decreasing honey lightness (L* value) and honey redness (a* value) but were not found to be significantly affected by honey yellowness (b* value) (p > 0.05), implying that darker honeys possess stronger ability to reduce enzymatic browning in white cabbage than lighter honeys. Furthermore, the effect of honey color on aroma and taste characteristics was not significant (p > 0.05). However, geographic location had an effect on flowery (b = −0.21, t = −2.48, p < 0.05) and acidic (b = −0.52, t = −3.47, p < 0.01) characteristics of honey, suggesting that honey aroma or taste is likely to be influenced by the location where honey is harvested rather than by its color.

Assessment of gas chromatography time-of-flight accurate mass spectrometry for identification of volatile and semi-volatile compounds in honey

The performance of gas chromatography (GC) combined with a hybrid quadrupole time-of-flight (QTOF) mass spectrometry (MS) system for the determination of volatile and semi-volatile compounds in honey samples is evaluated. After headspace (HS) solid-phase microextraction (SPME) of samples, the accurate mass capabilities of the above system were evaluated for compounds identification. Accurate scan electron impact (EI) MS spectra allowed discriminating compounds displaying the same nominal masses, but having different empirical formulae. Moreover, the use of a mass window with a width of 0.005Da provided highly specific chromatograms for selected ions, avoiding the contribution of interferences to their peak areas. Additional information derived from positive chemical ionization (PCI) MS spectra and ion product scan MS/MS spectra permitted confirming the identity of novel compounds. The above possibilities are illustrated with examples of honey aroma compounds, belonging to different chemical classes and containing different elements in their molecules. Examples of compounds whose structures could not be described are also provided. Overall, 84 compounds, from a total of 89 species, could be identified in 19 honey samples from 3 different geographic areas in the world. The suitability of responses measured for selected ions, corresponding to above species, for authentication purposes is assessed through principal components analysis.

Floral origin markers for authenticating Lavandin honey (Lavandula angustifolia x latifolia). Discrimination from Lavender honey (Lavandula latifolia)

The aim of this study was to identify the botanical origin of Lavandin honey, a monofloral product of recent proliferation obtained from a hybrid of the species Lavandula angustifolia and Lavandula latifolia. Lavandin was authenticated here in chemical, palynological and sensory terms, and discriminated from the more common Lavender honey (L. latifolia).A total of 14 physico–chemical parameters, 26 pollen types, 13 sensory attributes and 80 volatile compounds were identified and/or quantified for this purpose.High concentrations of γ-nonalactone, farnesol and acetovanillone, which were for the first time identified as components of honey aroma in this study, together with several lactones, dehydrovomifoliol, 4-methoxyacetophenone and decanal are proposed as chemical markers for authenticating Lavandin monofloral honey. In sensory terms, increased scores for “caramel” and “peach compote” sensations, together with an increased Rubus pollen content, provide additional useful information for the accurate authentication of Lavandin honey and its discrimination from Lavender honey (L. latifolia).Results showed enough floral markers to authenticate the botanical origin of Lavandin honey allowing its marketing as monofloral rather than generic honey.

Application of Selected Ion Flow Tube-Mass Spectrometry to the Characterization of Monofloral New Zealand Honeys

Honeys have a range of physicochemical and organoleptic properties, depending on the nectar source. Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS) is an emerging technology that quantifies volatile organic compounds (VOCs) to low concentrations (usually parts-per-trillion (ppt) levels) and is here applied to monitor the aromas in the headspace of different New Zealand monofloral honeys. Honey aromas arise from VOCs in the honeys that differ according to the flower type from which they were derived. In this exploratory study, the headspaces of nine monofloral New Zealand honeys (beech honeydew, clover, kamahi, manuka, rata, rewarewa, tawari, thyme, and vipers bugloss) were analyzed using SIFT-MS without sample preparation. The purpose of the investigation was to identify the major volatiles in each of the honeys and to test the feasibility of using SIFT-MS to distinguish between New Zealand monofloral honeys. In the nine monofloral honeys sampled, a clear distinction was observed between them based on their aroma signatures.

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.

Investigation of the aroma impact volatiles in Turkish pine honey samples produced in Marmaris, Datça and Fethiye regions by SPME/GC/MS technique

SummaryThe aroma impact volatiles of twenty‐four pine honey samples produced in Marmaris, Datça and Fethiye regions of Turkey were evaluated by solid phase micro extraction/gas chromatography/mass spectrometry (MS) technique and the results were evaluated by using the analysis of variance and Duncan tests. A total of eight common volatiles nonanal, nonanol, decanal, octanal, 16‐oxosalutaridine, dodecanal, nonadecane and pentadecane were detected in three regions. The total area of the common volatiles were 73.01%, 78.10% and 73.91% in Marmaris, Datça, and Fethiye regions, respectively. There were not significant differences (P &lt; 0.05) between the common volatiles detected in pine honey samples from three different regions. The major contributers to the pine honey aroma seems to be nonanal (aldehyde, citrus, fatty, floral, green, piny), nonanol (green, sweet, oily), decanal (soap, orange peel, tallow), and octanal (fat, soap, lemon, green). Nonanal seems to be the principal volatile component in all samples having average values of 46.82% in Marmaris, 51.67% in Datça and 48.63% in Fethiye regions.

Sensory and microbiological quality of yogurt drinks with prebiotics and probiotics

The popularity of dairy products fortified with prebiotics and probiotics continues to increase as consumers desire flavorful foods that will fulfill their health needs. Our objectives were to assess the sensory profile of drinkable yogurts made with prebiotics and probiotics and to determine the viability of the probiotics in the yogurt drink over the duration of storage. Thirteen trained descriptive panelists evaluated 10 yogurt drinks on a 16-point category scale. Three selected prebiotics, soluble corn fiber, polydextrose, and chicory inulin, were each present individually at an amount to claim an excellent source of fiber (5g of fiber/serving) or a good source of fiber (2.5g of fiber/serving) in 6 different yogurt drinks. Three additional yogurt drinks contained 5g of each of the separate prebiotics along with a mixture of the selected probiotics (Bifidobacterium lactis Bb-12 and Lactobacillus acidophilus LA-5). A control sample with no prebiotics or probiotics was also included in the experimental design. Data were analyzed by ANOVA, Fisher's least significant difference, and principal component analysis. Survival of the probiotics in the yogurt drinks during a 30-d refrigerated storage period was also analyzed. Results showed that clover honey aroma, buttermilk aroma, butter aroma, sweetness, sourness, chalky mouthfeel, and viscosity were identified as significant attributes in the yogurt drinks. Total variance explained by the principal component analysis biplot of factors 1 and 2 was 65%, which showed yogurt drinks with soluble corn fiber and inulin varying by the sweet versus sour attributes and yogurt drinks with polydextrose varying by the mouthfeel attributes. The viability study determined a 2- to 3-log decrease in the survival of probiotics in all of the yogurt treatments during a 30-d refrigerated storage period. Based on the results of the current study, only the polydextrose treatment would be an acceptable vehicle to deliver the probiotic health effects at the end of the 30-d storage period.

Development of a Structured Sensory Honey Analysis: Application to Artisanal Madrid Honeys

In this work a methodology to evaluate the sensory properties of honeys has been developed. The sensory analysis was carried out by means of a quantitative descriptive analysis (QDA) method, based on several reference scales, for the coverage of the designed range for each descriptor. The peculiarity of this sensory analysis is that the reference scales have been constituted by common foodstuffs agreed upon by consensus of the panel. The main sensory attributes evaluated in the analyses were: adhesiveness, viscosity, bitterness, aroma, sweetness, acidity, color and granularity. Both the intensity and persistence of honey aromas have also been estimated, together with the classification of the identified aromatic attributes into different groups. The method was applied to 55 artisanal honeys from Madrid (Spain) with the following results: (i) the developed sensory profile sheet allowed a satisfactory description of Madrid honeys; (ii) correlations between sensory attributes of three broad groups of Madrid honeys were obtained and (iii) aroma persistence, sweetness, bitterness, color and granularity appeared as the main sensorial characteristics of honey with discrimination power between floral and honeydew honeys.

Headspace, Volatile and Semi-Volatile Organic Compounds Diversity and Radical Scavenging Activity of Ultrasonic Solvent Extracts from Amorpha fruticosa Honey Samples

Volatile organic compounds of Amorpha fruticosa honey samples were isolated by headspace solid-phase microextraction (HS-SPME) and ultrasonic solvent extraction (USE), followed by gas chromatography and mass spectrometry analyses (GC, GC-MS), in order to obtain complementary data for overall characterization of the honey aroma. The headspace of the honey was dominated by 2-phenylethanol (38.3–58.4%), while other major compounds were trans- and cis-linalool oxides, benzaldehyde and benzyl alcohol. 2‑Phenylethanol (10.5–16.8%) and methyl syringate (5.8–8.2%) were the major compounds of ultrasonic solvent extracts, with an array of small percentages of linalool, benzene and benzoic acid derivatives, aliphatic hydrocarbons and alcohols, furan derivatives and others. The scavenging ability of the series of concentrations of the honey ultrasonic solvent extracts and the corresponding honey samples was tested by a DPPH (1,1-diphenyl-2-picrylhydrazyl) assay. Approximately 25 times lower concentration ranges (up to 2 g/L) of the extracts exhibited significantly higher free radical scavenging potential with respect to the honey samples.

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.

SPME followed by GC–MS: a powerful technique for qualitative analysis of honey volatiles

Volatile compounds from 40 honey samples of different botanic origin were analyzed by SPME followed by GC–MS. In order to obtain complementary data for an overall characterization of honey aroma, two different SPME fiber coatings (polyacrylate and carboxen/polydimethylsiloxane) were employed. The use of both fibers with a single chromatographic column afforded the identification or characterization, based on GC retention and mass spectral data, of a total of 193 volatile components. A total of 166 honey volatiles were characterized (146 identified) from CAR/PDMS data, this fiber being the most appropriate for isolation of low molecular weight compounds. Polyacrylate fiber was better for extraction of polar semivolatiles, allowing to identify 120 compounds and to characterize 132. Besides typical nectar components such as limonene, linalool, etc., different compounds from fermentation (ethanol and 2,3-butanediol), processing (furan derivatives), hive treatment (thymol), etc. were detected. Although many volatiles were common to most honey samples analyzed, other seemed to be characteristic of certain honey types.

Influence of simulated industrial thermal treatments on the volatile fractions of different varieties of honey

The aim of this study was to determine if the volatile fraction of honey is affected by the application of standard industrial thermal treatment processes. Four types of Spanish honey were studied: three of floral origin (citrus, rosemary and polyfloral) and the fourth from honeydew. Each sample of honey was divided into three parts: one was left untreated, one was liquefied (at 45 °C for 48 h) and the other was both liquefied and pasteurized (at 80 °C for 4 min). All the samples analyzed were characterized to determine their melissopalynological, physicochemical (pH, moisture, total acidity, conductivity, hydroxymethylfurfural, and diastase activity), and volatile profiles. Type of honey had a greater impact on volatile fraction variations than did heat treatment. The overall volatile profile of each kind of honey permitted the classification of the honeys by botanical origin, revealing that there were practically no differences between the raw, liquefied, and pasteurized samples of each honey. These findings suggest that industrial processes conducted under controlled conditions should not significantly alter the intrinsic aroma of honey.

Desarrollo de un método por microextracción en fase sólida para el análisis de la fracción volátil de la miel de abeja de Yucatán

The assessment of the botanical origin of unifloral honeys is an important application in food quality control. The aroma is a quality factor of great importance in foods. The aroma of bee honey depends on its volatile fraction composition, which is influenced by both nectar composition and floral origin, which could also be associated with the honey's botanical origin. One recent method involves the analysis of the volatile fraction of foods by different methods of extraction and chromatography techniques. Herein, a simple method for analysing honey volatile compounds was developed using solid-phase micro extraction (SPME). The influence of different conditions related to the isolation and concentration step, such as polarity and type of fiber for SPME, desorption time, ionic force, sample size, time and temperature of the extraction, dilution and temperature of equilibrium, was studied. Highly advantageous results were obtained by using fiber composed of 65 mm Polydimethylsiloxane/ Divinylbenzene (PDMS/DVB), addition of sodium chloride (20 %), desorption time (4 min), sample size (6 g), time (40 min) and temperature (70 oC) of the extraction, and equilibrium time (30 min), enabling an repeatability below 10 % for the volatiles. Differences on the chromatogram profiles, relating to the composition of honey volatiles, were obtained and these results allowed the differentiation of various Yucatan honeys.