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Himalayan balsam (Impatiens glandulifera Royle) is an invasive garden ornamental plant species originating from Asia, which produces significant amounts of nectar. In Croatia, it is widely distributed along the banks of the Mura River. Although this plant species is widespread in Europe, there are still no available scientific data about this unifloral honey type. The results showed that Himalayan balsam honey is characterized by the high presence of pollen grains in the pollen spectrum (59–85%), natural higher diastase activity (39.1 ± 7.98 DN), negative specific rotation (−21.2° ± 6.89) and an extra light amber color (48.5 ± 12.69 mm Pfund). The carbohydrate profile is characterized by monosaccharides fructose (39.34 ± 0.65 g/100 g) and glucose (31.91 ± 1.42 g/100 g) with a ratio >1.23, while the most commonly represented disaccharide was maltose (3.04 ± 0.79 g/100 g). The average total phenolic content was 130.97 ± 11.17 mg gallic acid/kg honey, and the average antioxidant capacity value was 225.38 ± 29.58 µM Fe(II). The major mineral element was K, with an average of 533.92 ± 139.70 mg/kg. The sensory profile was characteristic with a light orange color and medium-intensity odor and aroma. The crystallization rate was moderate and characterized by the appearance of opalescence and gelatinous forms of crystals. The results of this study provide the first insight into the melissopalynological, physico-chemical and sensory profile of Himalayan balsam honey.

Chemical characterization of bee pollen is of great importance for its quality estimation. Multifloral and unifloral bee pollen samples collected from continental, mountain and Adriatic regions of Croatia were analyzed by means of physico-chemical, chromatographic (GC-MS), and spectroscopic (FTIR-ATR) analytical tools, aiming to conduct a comprehensive characterization of bee pollen. The most distinctive unifloral bee pollen with regard to nutritional value was Aesculus hippocastanum (27.26% of proteins), Quercus spp. (52.58% of total sugars), Taraxacumofficinale (19.04% of total lipids), and Prunusavium (3.81% of ash). No statistically significant differences between multifloral and unifloral bee pollen from different regions were found for most of the physico-chemical measurement data, with an exception of melezitose (p = 0.04). Remarkable differences were found among the bee pollen HS VOCs. The major ones were lower aliphatic compounds, monoterpenes (mainly linalool derivatives, especially in Prunusmahaleb and P.avium bee pollen), and benzene derivatives (mainly benzaldehyde in T.officinale and Salix spp.). Aldehydes C9 to C17 were present in almost all samples. FTIR-ATR analysis revealed unique spectral profiles of analyzed bee pollen exhibiting its overall chemical composition arising from molecular vibrations related to major macromolecules—proteins, lipids, and carbohydrates (sugars).

Beeswax adulteration in the apiculture sector represents a growing problem worldwide due to the lack of clearly defined purity criteria, the absence of official quality (authenticity) controls, and the inconsistency of the analytical methods used for adulteration detection. Although beeswax authentication is implemented in other regulatory sectors (pharmaceutical and food industry), the classical physico-chemical analytical methods used for determination of beeswax purity exhibit inconsistencies for the detection of adulterants. In this study, an inventory was made on a comprehensive set of analytical methods and the corresponding purity criteria used for the detection of the most common beeswax adulterants (paraffin, stearin and/or stearic acid) from existing legislations and scientific literature. The selected analytical methods (classical physico-chemical, and advanced instrumental, i.e. chromatographic and spectroscopic analytical techniques) were weighted by three independent experts against two criteria: feasibility and analytical performance in detecting targeted adulterants. Classical methods for which measurement data were available (melting point and acid/saponification/ester values for paraffin-adulterated vs. non-adulterated beeswax samples) were retained and further validated by a receiver operating characteristic (ROC) analysis. These methods were also validated by generating the corresponding calibration curves for paraffin detection using paraffin-beeswax mixtures containing different proportions of paraffin (ranging from 5 to 95%, w/w). The results of the ROC analysis revealed that a tentative detection of paraffin in beeswax can be achieved by a combination of at least two physico-chemical methods. However, for a reliable detection of the most common adulterants in beeswax, physico-chemical methods should be complemented with advanced analytical tools. i.e. GC-MS, HTGC-FID (MS) and/or FTIR-ATR spectroscopy, depending on the expected adulterant.

The incidence of antibiotic resistance in pathogenic bacteria has become an alarming clinical and social problem. Therefore, the demand for alternative antimicrobial compounds has increased. In this study, a chemical profile of honey bee (Apis mellifera L.) venom (HBV) has been determined by HPLC and FTIR-ATR spectroscopy, and tested for antibacterial activity, as well as efficiency with regard to conventional antibiotics. The investigated HBV was of high quality with melittin and total protein contents of 70.10 ± 7.01%, and 84.44 ± 3.12 g/100 g, respectively. The purity of HBV was confirmed by FTIR-ATR spectral profiling, which revealed a unique pattern of absorption bands that are characteristic of its major fractions. In addition, HBV showed a broad spectrum of activity against all three tested biomasses of potentially pathogenic Gram-positive and Gram-negative bacteria with MIC values ranging between 12.5 and 200 µg/mL, and MBC between 12.5 and 400 µg/mL. When compared to conventional antibiotics, HBV (400 µg) showed up to 27.8% efficiency of tetracycline (30 µg), 52.2% erythromycin (15 µg), 21.2% ciprofloxacin (5 µg), and 34.6% of ampicillin-sulbactam (20 µg). The overall results demonstrate the therapeutic potential of the analyzed HBV.

Hemolymph is a colorless or slightly yellowish liquid of the open circulatory system of the honey bee (Apis mellifera L.) which represents a functional equivalent of vertebrate blood and lymph. It has a complex chemical composition and contains water, numerous proteins, amino acids, carbohydrates (glucose, fructose, trehalose) and lipid-based components. Understanding the biochemical features of the hemolymph is of great importance as it reflects the physiological state of honey bee organism. The aim of this study was to determine the overall biochemical composition of honey bee hemolymph based on chemical characterization using Fourier transform infrared (FTIR) spectroscopy. Individual hemolymph samples (~4-5 μL/bee) of two age groups of workers (newly emerged bees-1 day old, n=31 ; foragers-42 days old, n=18) were collected by extraction from the thorax after removing the legs (to avoid contamination with nectar and/or gut content that often occurs when applying other extraction methods) using 10 μL glass microcapillary tubes. The IR spectra of individual hemolymph samples were analysed by FTIR-ATR (Attentuated Total Reflectance) recording technique. The results have revealed a unique IR chemical fingerprint of honey bee hemolymph. Characteristic age-related spectral features indicating compositional variations between newly emerged bees and foragers were observed. The major differences were reflected in the higher proportion of proteins, amino acids and lipid-based components in the hemolymph of newly emerged bees compared to foragers hemolymph. Contrary, it was observed that foragers hemolymph contains higher amount of water and carbohydrates which can be associated with age/task relating metabolic changes - foraging activity (nectar collection).

Analytical parameters were determined for the first time in honey produced in the honeycomb constructed on comb foundations adulterated with 90% of paraffin (PF-H) and compared to honey ripened in genuine beeswax (BWF-H) using physico-chemical and spectroscopic techniques (1H NMR, FTIR-ATR, HS-SPME/GC–MS). Water content was significantly higher (SH) and glucose/water ratio significantly lower in PF-H samples. The contents of acetic and citric acid were marginally significantly higher (MSH) in PF-H samples. These findings suggest that adulterated beeswax affects composition of honey as the set of altered parameters indicate chemical changes leaning towards fermentative processes. Moderately changed headspace chemical profile of PF-H honey was determined depending on the floral source (pentanal, α-pinene and benzaldehyde were SH in BWF-H sunflower honey ; butanal was MSH, and 2-phenylethanol was more abundant in BWF-H black locust honey). Higher percentage of nonanal, octane and β-damascenone were found in PF-H samples that could indicate more intensive oxidation.

The European Food Safety Authority (EFSA) develops methodologies and tools for the detection of emerging risks in food and feed. This includes the identification of drivers of emerging risks, such as food frauds, which requires innovative approaches. In this study, an unsupervised machine learning technique called the Latent Dirichlet Allocation (LDA) topic model, was applied on a media corpus in the view of detecting rapidly specific food fraud incidents in the media, i.e. on the Europe Media Monitor Medical Information System (EMM/MEDISYS). LDA topic model can explore large collection of documents discovering the themes associated with the corpus and organize and summarize text documents identifying topics comprised in them, where a topic is defined as a pattern of words with their probability to belong to it. As a specific food fraud incident, beeswax adulteration was taken as an example. Beeswax can be adulterated for financial gain, and, although it is a product from apiculture, it might enter the food chain when it is introduced as honeycomb in honey pots. With the beeswax example, a total of 2276 news articles were retrieved on EMM/MEDISYS and classified into 10 topics showing different levels of relatedness to beeswax adulteration. A manual screening of all articles allowed to validate the classification made by the topic model. The topics that were found the most relevant contained indeed articles on beeswax adulteration incidents reported from official sources. In addition, those topics contained signals of potential emerging risks in the cosmetic and food wrapping sectors. The remaining topics highlighted the emergence of new beeswax market opportunities which supported the identified signals. It is concluded that the LDA topic model can be used to process rapidly information in the media, support the definition of more specific food fraud filters on EMM/MEDISYS and be of direct use for all stakeholders involved in the monitoring, assessment and management of food frauds.

Samples of Satsuma mandarin (Citrus unshiu Marc.) nectar, honey sac content and honey were analyzed by FTIR-ATR spectroscopy and reference methods. The spectral analysis allowed detection of the major chemical constituents in C. unshiu nectar- to-honey transformation pathway thus providing information on the intensity and location of the compositional changes occurring during this process. The preliminary results showed that in average more than one-third of sugar-related nectar-to-honey conversion takes place directly in the honey sac ; the average sugar content (w/w) was 17.93% (nectar), 47.03% (honey sac) and 79.63% (honey). FTIR-ATR results showed great spectral similarity of analyzed honey samples and small degree variations in both sugar and water content in nectar samples. The spectral data revealed distinctive differences in the chemical composition of individual honey sac contents with the most intensive and complex absorption envelope in the spectral region between 1175 and 950 cm-1 (glucose, fructose and sucrose absorption bands).

Six hundred thirty-two honey samples from Croatia were analyzed by reference methods (physicochemical and melissopalynological analyses), from which 506 were assigned to one of nine unifloral honey types (black locust, sweet chestnut, lime, sage, heath, mandarin, false indigo, immortelle and winter savory). Vibrational spectra of honey samples recorded using Fourier transform infrared (FTIR) spectroscopy and attenuated total reflection (ATR) technique were subjected to comprehensive chemometric assessment involving optimization of data preprocessing and multivariate statistical analyses, namely principal component analysis, partial least squares regression, partial least squares discriminant analysis and receiver operating characteristic (ROC) analysis. A specially designed hybrid multidimensional model (partial least squares-linear discriminnat analysis) was used to assess a relationship between honey IR spectra and relative frequencies of pollen grains (pollen spectrum) present in selected honey samples. The study demonstrated that a targeted spectral profiling, i.e., preprocessing of a fingerprint spectral region (1, 800–700 cm−1) by particular Savitzky–Golay filtering parameters and ROC modelling approach, enables accurate classification (100 % correct classification) of unifloral honeys by their botanical origin with low misclassification risk (MR = 0.099) and negligible small number of misclassified samples (1–2 per class—honey type). The results have also revealed good predictive strength of FTIR-ATR spectroscopy for melissopalynologycal data.

There is no report on the chemical composition of alder buckthorn (Rhamnus frangula L.) honey and therefore volatile organic compounds (VOCs) were investigated for the first time as well as their composition after short-term heating. The electrical conductivity of the samples was 0.90 - 0.98 mScm-1 (specificity of alder buckthorn honey), and pH values were 4.00 - 4.33. The melissopalynological analysis revealed R. frangula L. as dominant plant species (52-93%) in all samples. Accompanying minor plant species were also determined (Castanea sativa L., Centaurea jacea L., Lotus corniculatus L., Prunus spp., Salix spp., Apiaceae, Asteraceae, Acer spp. and Cornus sanguinea L.). The VOCs from R. frangula L. honey were isolated by headspace solid-phase microextraction (HS-SPME) and ultrasonic solvent extraction (USE) and analysed by GC-FID and GC-MS. To investigate the influence of short-term heating, selected sample was heated 3h at 100 oC with and without H2O addition. The most representative chemical profile of R. frangula L. honey is obtained by HS-SPME containing benzaldehyde, hotrienol and 4-ketoisophorone. USE contributed to the honey characterization, mainly by vomifoliol identification. The majority of compounds found in USE were higher aliphatic alcohols. The influence of short-term heating to R. frangula L. honey is strongly dependent on H2O addition. Namely, more artefacts (furan derivatives, particularly 5-hydroxymethylfurfural) were formed during heating of the honey dissolved in H2O in comparison with direct honey heating.