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Consumers demand to know the floral origins of honeys. Therefore, the use of simple and reliable techniques for differentiating among honeys by their origins is necessary. Multivariate statistical techniques and near infrared spectroscopy applied to palynological and mineral characteristics make it possible to differentiate among the types of honey collected from Northwestern Spain. Prediction models using a modified partial least squares regression for the main pollen types (Castanea, Eucalyptus, Rubus and Erica) in honeys and their mineral composition (potassium, calcium, magnesium and phosphorus) were established. Good multiple correlation coefficients (higher than 0.700) and acceptable standard errors of cross-validation were obtained. The ratio performance deviation exhibited a good prediction capacity for Rubus pollen and for Castanea pollen, whereas for minerals, for Eucalyptus pollen and for Erica pollen the ratio performance deviation was excellent. Near infrared spectroscopy was established as a rapid and effective tool to obtain equations of prediction that contribute to the honey typification., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Simple Summary: The yellow-legged hornet is an invasive species from southeast Asia that has turned the European beekeeping sector upside down. The spread of this species has been advancing in recent years, and today, several European countries are threatened by Vespa velutina. The need to study its behavior is urgent given the increasingly evident economic and environmental impacts. In this regard, there is little information about the feeding habits and the resources it uses during the life cycle. Like other Hymenoptera, hornets require carbohydrates and proteins as their primary nutrients. Sugary secretions such as floral nectar, honeydew, or fruit juices are the main sources of carbohydrates but the protein intake is provided by the consumption of a diverse diet of insects such as the honey bee. There is scarce information on the presence of pollen grains in the gastrointestinal content of larvae other than secondary contamination from hunting. This content could represent the surrounding flora of its habitat that is used as a resource. Therefore, the objective of this study was to describe the main pollen types present in the gastrointestinal system of larvae taken from V. velutina nests. Vespa velutina is an invasive species that exhibits flexible social behavior, which may have contributed to its introduction in several European countries. It is important to understand its behavior in order to combat the effects of its introduction in different areas. This implies knowing the resources that it uses during its biological cycle. Hornets require protein resources taken from insects and organic matter as well as carbohydrates as an energy source to fly and also to forage for food and nest-building materials. The gastrointestinal tract of adults and larvae contains a wide variety of pollen types. The identification of this pollen in larvae collected from nests could offer information about the plant species that V. velutina visits as a foraging place. The main objective of this research was to study the pollen content in the gastrointestinal tract of larvae. Patterns of pollen content and pollen diversity were established according to the nest type, altitude, season, and location in the nest comb. The abundance of pollen types such as Eucalyptus, Castanea, Foeniculum vulgare, Hedera helix, Taraxacum officinale, Echium, or Cytisus pollen type stands out in many of the samples. [ABSTRACT FROM AUTHOR]

Raw honey is a food with a close relation to the territory in which it is produced because of factors such as soil conditions, weather patterns, and plant communities living in the area together. Furthermore, beekeeping management affects the properties of honey. Protected Geographical Indication Miel de Galicia protects the honey produced in Galicia (Northwest Spain). Various types of honeys (362 samples) from this geographical area were analyzed using chemometric techniques. Principal component analysis was favorable to analyzing the physicochemical and pollen variables with the greatest weight in the differentiation of honey. The linear discriminant analysis correctly classified 89.8% of the samples according to the botanical origin using main pollen spectra and physicochemical attributes (moisture, pH, electrical conductivity, diastase content, phenols, flavonoids, and color). Regarding unifloral honey, blackberry, eucalyptus, and heather honeys were correctly grouped, while five chestnut honeys and fourteen samples of honeydew honeys were misclassified. The chestnut and honeydew honeys have similar physicochemical properties and frequently similar pollen spectra profiles complicating the differentiation. Experimental evidence suggests the potential of multivariate statistics in the characterization of honey of the same geographical origin. Therefore, the classification results were good, with electrical conductivity, total phenol content, total flavonoid content and dominant pollens Eucalyptus, Erica, Rubus and Castanea sativa as the variables of higher importance in the differentiation of botanical origin of honeys. [ABSTRACT FROM AUTHOR]

A melissopalynological study was carried out on 46 samples of Ziziphus lotus honey from Laghouat and Djelfa region (central Algeria). The number of pollen types identified per honey sample ranges between nine and 39 with a mean of 24. These correspond to 52 botanical families with 79 different pollen types in the whole samples. Asteraceae and Fabaceae families were present in all the samples where as Apiaceae, Brassicaceae and Nitrariaceae (Peganum harmala) were identified in more than 90%. Other plant families as Boraginaceae, Cistaceae, Myrtaceae, Oleaceae, Salicaceae or Urticaceae were identified in more than 50% of the samples but frequently as minor pollen. Ziziphus lotus pollen had a mean content of 68.9% (with a range of 45.3% to 93.4%). The secondary pollen types were Ononis natrix, Peganum harmala, Brassica napus, Echium and Olea europaea. Regarding the important pollen it is highlighted the presence Lotus t., Eucalyptus, Pimpinella anisum t., Trifolium t., Eryngium campestre t., Centaurea t., Galega officinalis t., Citrus or Scrophularia t. The sedra honeys of the studied region are characterised by their high content in pollen grains with a mean content of 188 403 grains/10 g. The presence of some pollen types in the pollen spectra of honeys such as Peganum harmala, Thapsia garganica, Launaea, Muscari comosum, Carthamus or Limonium bonduellei together several Asteraceae as Centaurea, Taraxacum, Carduus, Artemisia and Matricaria was proposed as geographical markers of this honey type. [ABSTRACT FROM AUTHOR]

Consumers are exhibiting increasing interest in honeydew honey, principally due to its functional properties. Some plants can be sources of honeydew honey, but in north-western Spain, this honey type only comes from Quercus pyrenaica. In the present study, the melissopalynological and physicochemical characteristics and the antioxidant properties of 32 honeydew honey samples are described. Q. pyrenaica honeydew honey was defined by its colour, high pH, phenols and flavonoids. Multivariate statistical techniques were used to analyse the influence of the production year on the honey's physicochemical parameters and polyphenol content. Differences among the honey samples were found, showing that weather affected the physicochemical composition of the honey samples. Optimal conditions for oak growth favoured the production of honeydew honey. [ABSTRACT FROM AUTHOR]

Fifty-four honey samples collected over two consecutive harvest seasons (2009–2010) from different floristic areas of Romania were analysed. A melissopalynological analysis including qualitative and quantitative analyses was carried out in order to identify the principal pollen types in Romanian honeys and therefore, the important plants exploited byApis melliferain this country. Seventy-seven pollen types from 35 botanical families were identified. The main pollen forms were:Brassica napus-type,Tilia,Helianthus annuus,Robinia pseudoacacia,Prunus,Castanea sativa,Fragaria-type andPlantago-type. Honey samples were classified as: acacia honey (Robinia pseudoacacia), lime honey (Tilia), rape honey (Brassica napus-type), sunflower honey (Helianthus annuus), cherry honey (Prunus). Three of them were honeydew honeys whereas the others were all polyfloral. The results from this study can be used as a palynological baseline data of Romanian artisanal honeys. [ABSTRACT FROM AUTHOR]

Abstract: Twenty-three honey samples from Galicia (Northwest Spain) were analysed to determine their botanical origin, phenolic compounds and antibacterial activity. In all samples Rubus pollen was predominant, followed by that of Castanea sativa. Other important pollens found belong to Cytisus type, Trifolium repens, Echium, Eucalyptus globulus, Erica umbellata, Erica cinerea, Campanula type and Frangula alnus. Eight phenolic compounds (caffeic, p-coumaric and ellagic acids, pinocembrin, chrysin, galangin, tectochrysin and kaempferol) were determined by solid-phase extraction (SPE) followed by HPLC/DAD analysis. p-Coumaric and ellagic acids were the main constituents of the phenolic fraction (ca. 5.5mg/kg each, mean value), followed by the pair chrysin plus galangin (ca. 1.2mg/kg, mean value) and pinocembrin (ca. 1.0mg/kg, mean value). Antibacterial activity was checked against five Gram-positive bacteria (Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus luteus, Enterococcus faecalis and Bacillus cereus) and four Gram-negative bacteria (Proteus mirabilis, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhimurium). B. cereus and P. mirabilis were the most sensitive microorganisms. This is the first study concerning the phenolic compounds and antibacterial activity of Rubus honey, which proved to be a good source of phenolic compounds and antimicrobial agents with potential health benefits. [Copyright &y& Elsevier]

Summary A study of Rubus honey was conducted to determine their sugar composition, physicochemical properties, phenol and flavonoid contents, and sensorial and pollen characteristics. The principal pollen types present in the studied samples were Rubus, Castanea and Cytisus. Other pollen types such as Trifolium, some Erica sp., Eucalyptus or Echium were present in more than 50% of the pollen spectra. The sensorial characteristics of Rubus honey were amber-to-amber dark in colour, floral and/or vegetal olfactory perceptions with medium-to-low intensity and persistence, medium floral aftertaste and a fruity aroma. Physicochemical analysis showed that the honey had good quality and freshness. Phenol and flavonoid contents varied greatly and were related to the mineral content and colour of the honey. A stepwise regression analysis was performed using colour as the dependent variable, and flavonoid, electrical conductivity, and Rubus pollen as the independent variables. [ABSTRACT FROM AUTHOR]

The microscopic analysis of honeys has led to the identification of different structures, including pollen grains, fungal spores, yeast, algae and soot particles. Pollen grains are the most studied elements, while others, like fungal spores and yeast, are less well known. Some of these elements come from primary sources and are associated with the presence of honey dew, such as Alternaria, Stemphylium, and Leptosphaeria. A variety of yeasts are regularly present in the floral nectar of many plant species where they frequently reach high densities. A melissopalynological method was used to identify some of these microscopic elements, their frequency in honeys and the relationships with the ecological origin of the product. The pollen types most frequently identified were Castanea sativa, Rubus, Cytisus type, Eucalyptus and Erica. Cladosporium conidia were identified in 64% of the samples, Metschnikowia cells were present in more than 50% of the honeys and some plant pathogenic fungi (Leptosphaeria, Stemphylium and Urediniospores among others) were also frequently present. The presence of Metschnikowia cells was associated with blossom honey and the presence of some fungal spores was associated with honey dew contributions. [ABSTRACT FROM AUTHOR]

Siliceous marine microfossils were unexpectedly discovered during the analysis of flower honey samples from Poland and Tunisia. The microfossils were represented by protist with siliceous skeletons: silicoflagellates, diatoms, and endoskeletal dinoflagellates. This is the first record of such microfossils in honeys. Based on the high percent of anemophilous pollen grains and spores in the sample, it was hypothesized that silicoflagellates were deposited from the air onto the nectariferous flowers, then bees harvested them with the nectar. Based on the comparison of pollen content of honeys and flowering calendar of Tunisia, the harvest time of honey was identified as a period between 1 April and 31 May 2011. Trajectory analysis of air masses in this period confirmed that siliceous microfossils could be aerosolized by wind from the rocks of the so-called Tripoli Formation of Messinian age (6–7 Ma). Similar to the Tunisian case, the Polish trajectory simulation also supports the hypothesis of atmospheric transport of silicoflagellates from outcrops of Oligocene age in the Polish Outer Carpathians. In the case of diatom content of honey, however, the source can be both natural (wind) and artificial (diatomaceous earth filters). For a correct determination, natural sources of siliceous bioparticles, such as wind transport from nearby outcrops should be also considered. Silicoflagellates could be used as complementary indicators of the geographical origin of honeys collected in areas characterized by diatomite outcrops, supporting the results obtained with other methods; thus, such indicators merit further studies within the area of honey authenticity. [ABSTRACT FROM AUTHOR]

This study aimed to characterize the honeys of Babors Kabylia through sensory, melissopalynological and physico-chemical parameters. Thirty samples of honey produced in this region were collected over a period of two years and analyzed. All the samples presented physico-chemical parameters in conformity with legislation on honey quality, with few exceptions, linked mainly to beekeeping management. The pollen spectrum revealed a great diversity with 96 pollen types. The main pollen types were spontaneous species as Fabaceae (Hedysarum, Trifolium, Genisteae plants), Asteraceae plants, Ericaceae (Erica arborea L.) or Myrtus and Pistacia. The sensory properties of samples showed a high tendency to crystallization, the colors were from white to brown, but most of them had gold color. Smell and odor corresponded mainly to vegetal and fruity families and in taste perceptions besides sweetness highlighted sourness and saltiness notes. Seventeen samples were polyfloral, one was from honeydew and twelve were monofloral from heather, genista plants, sulla, blackberry or Asteraceae. Heather and the honeydew samples showed the darkest color, the highest electrical conductivity and phenol and flavonoid content. A statistical analysis based on the most representative pollen types, sensory properties and some physico-chemical components allowed the differentiation of honey samples in terms of botanical origin. [ABSTRACT FROM AUTHOR]

The palynological and physicochemical analysis of 62 honey samples produced in different biogeographical areas of Algeria was conducted. Results showed high variety in the botanical origin of samples and their physicochemical profile. Twenty-six samples were polyfloral honey, 30 were unifloral honey from different botanical sources such as Eucalyptus, Citrus, Apiaceae, Punica, Erica, Rosmarinus, Eriobotrya, or Hedysarum, and 6 were characterized as honeydew honey. Pollen analysis allowed the identification of 104 pollen types belonging to 51 botanical families, whereas the physicochemical profile showed important variations between samples. Multivariate techniques were used to compare the characteristics of samples from different biogeographical areas, showing significant differences between humid-area samples, located in the northeast of the country, and samples taken in semiarid, subhumid, and arid zones. Principal-component analysis (PCA) extracted nine components explaining 72% of data variance, being 30%, the sum of Component 1 and Component 2. The plot of both components showed samples grouped upon botanical and geographical origin. The results of this paper highlighted the great variability in honey production of Algeria, evidencing the importance of honey characterization to guarantee authenticity and to valorize local production. [ABSTRACT FROM AUTHOR]

This work investigates the similarities and differences of oak honeydew (Quercus pyrenaica Willd.) and evergreen honeydew (Quercus ilex L.) honey produced in Spain. For this purpose, the physicochemical characteristics of 17 samples from oak honeydew and 11 samples from evergreen honeydew collected in different geographical regions were analyzed. All the samples accomplished European Union requirements for honey consumption. Both honey types had amber dark color; however, the evergreen oak honey was clearer than oak honey, having higher mean values in a* and b* coordinates of CIELab scale. In general, both honey types exhibited high electrical conductivity, a moderate value of pH, medium to low water content, and high diastase activity. The reducing sugar content was significantly lower and maltose content was significantly higher in evergreen honeydew. In addition, total phenols and total flavonoid contents, the antioxidant activity and the melissopalynological analysis was performed. The oak honeydew honey had a higher abundance of Castanea, Rubus and Erica pollen grains, while the evergreen oak honeydew honey had a higher abundance of Lavandula, Olea europaea or Anthyllis cytisoides. A multivariate analysis using the most representative pollen types and physicochemical components facilitated the differentiation of the honey samples, thus this information can be useful for the honey characterization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three types of monofloral honey produced in arid and semiarid areas of Algeria has been characterized according to palynological analysis and volatile profile. • Some volatile compounds were found as characteristic for Retama sphaerocarpa , Atractylis serratuloides and Eruca sativa honey. • Some compounds were characteristics such as dimethyl trisulfide in Eruca honey, lilac aldehyde and lilac aldehyde D in Retama honey and 2-naphthalene methanol, decahydro-α,α,4a-trimethyl-8-methylene-, [2R-(2α,4aα,8aβ)], 1,6,10-dodecatrien-3-ol,3,7,11-trimethyl-, (E), 1,6-Octadien-3-ol,3,7- dimethyl and phenol, 2-methoxy in Atractylis honey. The volatile fraction of three monofloral honey types produced in arid and semiarid areas of Algeria was studied to establish a link between their chemical composition and their botanical origin. Palynological analysis was performed to confirm the main botanical origin. Volatile extraction using HS-SPME coupled to GC–MS revealed exclusive components for each type: 1,6,10-dodecatrien-3-ol,3,7,11-trimethyl-, (E); 1,6-octadien-3-ol,3,7- dimethyl; phenol, 2-methoxy and 2-naphtalene methanol, decahydro-α,α,4a- trimethyl-8-methylene-, [2R-(2α,4aα,8a,8aβ)] for Atractylis honey, lilac aldehyde and lilac aldehyde D for Retama honey, and dimethyl trisulfide for Eruca. The PCA analysis made it possible to correlate some volatile compounds with the most important pollen types, and to evaluate the authenticity related to the geographical and botanical origin of the honey. [ABSTRACT FROM AUTHOR]

Abstract: Fifty two honey samples from different regions of Romania were used in order to define the rheological properties and their relations with the sugar composition and palynological characteristics. The botanical origin of the samples was tested by a pollen analysis. The result let to classify 14 samples as linden honey, 11 as black locust, 11 as rape, 4 as sun-flower, 3 as honeydew and 9 multifloral honeys. The carbohydrate profile is performed by HPAEC with pulsed amperometric detection. Six sugars were identified and quantified. The glucose, fructose, maltose and sucrose are present in all the samples, while melezitose and trehalose are detected only in honeydew samples. The mean values of glucose and fructose are 33.3 and 39.8%, respectively. The dynamic rheological measurements show that G″ was much greater than G′, confirming the viscous nature of honey. The rheograms of honey samples at different temperatures (10–40°C) show the Newtonian behavior of all the samples, excepting rape and honeydew honeys which formed a hysteresis loop. [Copyright &y& Elsevier]