Labeling Regulations and Quality Control of Honey Origin: A Review

Elemental Fingerprinting Combined with Machine Learning Techniques as a Powerful Tool for Geographical Discrimination of Honeys from Nearby Regions

Discrimination of honey based on geographical origin is a common fraudulent practice and is one of the most investigated topics in honey authentication. This research aims to discriminate honeys according to their geographical origin by combining elemental fingerprinting with machine-learning techniques. In particular, the main objective of this study is to distinguish the origin of unifloral and multifloral honeys produced in neighboring regions, such as Sardinia (Italy) and Spain. The elemental compositions of 247 honeys were determined using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The origins of honey were differentiated using Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA), and Random Forest (RF). Compared to LDA, RF demonstrated greater stability and better classification performance. The best classification was based on geographical origin, achieving 90% accuracy using Na, Mg, Mn, Sr, Zn, Ce, Nd, Eu, and Tb as predictors.

Botanical Origin Influence on Some Honey Physicochemical Characteristics and Antioxidant Properties

Five types of honey (multifloral, sunflower, linden, rapeseed, and acacia), from Southern Romania, were classified using chemometrics methods coupled with IR spectroscopy. The botanical origin's effect on the physicochemical characteristics of honey was studied to highlight the most valuable plant source of honey. Except for antioxidant activity, the moisture, ash, electrical conductivity (EC), pH, free acidity (FA), total sugar content (TSC), hydroxymethylfurfural (HMF), total phenolic (TPC), tannin (TTC), and flavonoid content (TFC) were significantly influenced by the botanical origin of the honey. The results showed that sunflower honey had the highest moisture (15.53%), free acidity (16.67 mEq kg^-1), electrical conductivity (483.92 µS cm^-1), phenolics (167.59 mg GAE 100 g^-1), and flavonoids (19.00 mg CE 100 g^-1), whereas multifloral honey presented the highest total sugar content (69.64 g Glu 100 g^-1). The highest HMF content was found in linden honey (33.94 mg kg^-1). The HMF contents of all tested honey were within the standard recommended limit, and they confirmed that the tested honey was free of any heat treatment. All five types of tested honey presented a safe moisture content for storage and consumption (12.21-18.74%). The honey's free acidity was in the range of 4.00 to 25.00 mEq kg^-1; this indicated the freshness of the samples and the absence of any fermentation processes in the tested honey. Honey with a total sugar content over 60% (except for linden honey, with 58.05 g glucose 100 g^-1) showed the characteristic of nectar-derived honey. The elevated antioxidant activity of honey was correlated with its high moisture, flavonoids, and HMF, whereas the tannins and HMF were positively correlated with ash and electrical conductivity. The higher content of phenolics, flavonoids, and tannins was correlated with higher free acidity. The chemometric method, coupled with ATR-FTIR spectra, revealed a clear separation between linden honey from acacia, multifloral, and sunflower honey.

Calluna vulgaris as a Valuable Source of Bioactive Compounds: Exploring Its Phytochemical Profile, Biological Activities and Apitherapeutic Potential

Calluna vulgaris, belonging to the Ericaceae family, is an invasive plant that has widely spread from Europe all across Asia, North America, Australia and New Zealand. Being able to survive in rigid soil and environmental conditions, it is nowadays considered to be of high nature-conservation value. Known for its nutritional and medicinal properties, C. vulgaris stands out for its varied physiochemical composition, spotlighting a wide range of biological activity. Among the most important bioactive compounds identified in C. vulgaris, the phenolic components found in different parts of this herbaceous plant are the main source of its diverse pro-health properties (antioxidant, anti-inflammatory, antimicrobial, chemoprotective, etc.). Nonetheless, this plant exhibits an excellent nectariferous potential for social insects such as honeybees; therefore, comparing the bioactive compounds observed in the plant and in the final product of the beehive, namely honey, will help us understand and find new insights into the health benefits provided by the consumption of C. vulgaris-related products. Thus, the main interest of this work is to review the nutritional profile, chemical composition and biological activities of the C. vulgaris plant and its related honey in order to encourage the future exploration and use of this health-promoting plant in novel foods, pharmacological products and apitherapy.

Comb honey and Processed honey of Croton macrostachyus and Schefflera abyssinica honey differentiated by Enzymes and Antioxidant properties, and botanical origin

In this study, comb and industrially processed honey samples collected from Bonga forest were investigated in relation to Melissopalynology and enzyme content, antioxidant and physicochemical properties. Melissopalynology categorized honey samples as Croton macrostachyus and Schefflera abyssinica honey. The physicochemical properties of the honey were determined using the Association of Official Analytical Chemists (AOAC) and International Honey Commission (IHC) methods. The enzymatic and antioxidant properties of honey were evaluated using the spectrophotometric method. The highest enzyme activity was observed in Croton macrostachyus comb honey (diastase = 7.44 ± 0.13°Schade and invertase = 13.97 ± 0.2 Invertase number (IN). Croton macrostachyus processed honey exhibited the highest values in flavonoids (83.36 ± 1.65 mg Catechin equivalents (CEQ)/100g)), Ferric reducing antioxidant power (FRAP) (69.94 ± 1.0 mg Ascorbic acid equivalents (AAE)/100g), and Inhibitory Concentration (IC₅₀) (136.3 ± 0.00 mg/ml), while Schefflera abyssinica comb honey had stronger 1,1-diphenyl-2-picrylhydrazyl radical scavenging (DPPH) (49.47 ± 0.00%) activity. The principal component analysis revealed that enzymes can be associated with comb honey, and antioxidants with processed honey. Thus, comb and processed honey can be differentiated based on the enzyme level, and Croton macrostachyus and Schefflera abyssinica honey can be identified using pollen analysis.

Development and shelf-life assessment of soft-drink with honey

This scientific work describes research that aims to determine the physicochemical parameters of homogenized honey and its safety indicators based on the determination of toxic metals and radionuclides. A series of experimental studies were conducted to develop and study recipes for honey water based on different types of honey collected in the Lviv region of Ukraine, namely acacia, buckwheat, sunflower, coriander, goldenrod, linden, and weeds. According to the results of experiments, it was found that the studied honey meets all the requirements presented in the standard for natural honey. And the results obtained to determine the dry matter content and pH allowed to blend different types of honey and get honey drinks, which will expand the range of non-carbonated products, which is very popular, especially in summer, and drink this drink during the year. To prolong the shelf life of honey drinks, it is recommended to add citric acid in an amount of 1% by weight of the drink and sodium benzoate as a preservative in an amount of 0.1%. The quality of the obtained honey water samples was assessed using organoleptic evaluation and physicochemical parameters. The resulting beverages have good organoleptic characteristics and can be offered for products in the industry.

Analytical Strategies for LC-MS-Based Untargeted and Targeted Metabolomics Approaches Reveal the Entomological Origins of Honey

A comprehensive liquid chromatography-mass spectrometry (LC-MS)-based metabolomics approach was developed to discriminate honey harvested from Apis mellifera ligustica Spinola (A. mellifera) and Apis cerana cerana Fabricius (A. cerana). Based on an untargeted strategy, ultrahigh-performance liquid chromatography electrospray ionization quadrupole orbitrap high-resolution mass spectrometry (UPLC Q-Orbitrap) was combined with chemometrics techniques to screen and identify tentative markers from A. mellifera and A. cerana honey. In targeted metabolomics analysis, a sensitive method of solid-phase extraction followed by ultrahigh-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry (UPLC-MS/MS) was established for quantifying three markers, and the results showed that 3-amino-2-naphthoic acid and methyl indole-3-acetate could be considered markers of A. cerana honey, as they were present in higher amounts in A. cerana honey than in A. mellifera honey, whereas kynurenic acid was determined to be a marker of A. mellifera honey. This work highlights critical information for the authentication of A. cerana and A. mellifera honey.

MIR spectroscopy versus MALDI-ToF-MS for authenticity control of honeys from different botanical origins based on soft independent modelling by class analogy (SIMCA) - A clash of techniques?

In this study, highly reproducible MIR spectroscopy and highly sensitive MALDI-ToF-MS data were directly compared for the metabolomic profiling of monofloral and multifloral honey samples from three different botanical origins canola, acacia, and honeydew. Subsequently, three different classification models were applied to the data of both techniques, PCA-LDA, PCA- kNN, and soft independent modelling by class analogy (SIMCA) as class modelling technique. All monofloral external test set samples were classified correctly by PCA-LDA and SIMCA with both data sets, while multifloral test set samples could only be identified as outliers by the SIMCA technique, which is a crucial aspect in the authenticity control of honey. The comparison of the two used analytical techniques resulted in better overall classification results for the monofloral external test set samples with the MIR spectroscopic data. Additionally, clearly more multifloral external samples were identified as outliers by MIR spectroscopy (91.3%) as compared to MALDI-ToF-MS (78.3%). The results indicate that the high reproducibility of the used MIR technique leads to a generally better ability of separating monofloral honeys and in particular, identifying multifloral honeys. This demonstrates that benchtop-based techniques may operate on an eye-level with high-end laboratory-based equipment, when paired with an optimal data analysis strategy.

Cornflower Honey as a Model for Authentication of Unifloral Honey Using Classical Methods Combined with Plant-Based Marker Substances Such as Lumichrome

According to legislation, unifloral honeys are characterized by their organoleptic, physicochemical, and microscopic properties. Melissopalynology is the established method for identifying the pollen taken up with the floral nectar by forager bees and is used for authentication of the nectar sources in honey. For cornflower honey (Centaurea cyanus), the pollen input does not correlate with the nectar input, because the nectar is produced both in floral and in extrafloral nectaries. The well-known cornflower marker lumichrome has now also been detected in the extrafloral nectar. Therefore, lumichrome is a suitable marker substance for cornflower honey. Four different methods for the sole analysis of lumichrome in honey were validated and compared. Studies over nine years have shown that unifloral cornflower honey should contain approximately 35 mg/kg lumichrome. For a further differentiated cornflower honey specific verification, other nonvolatile compounds like 7-carboxylumichrome and volatiles, such as 3,4-dihydro-3-oxoedulan I and 3,4-dihydro-3-oxoedulan II, should be analyzed. This enables a more specific accuracy for the classification of unifloral cornflower honey.

Laser-Induced Breakdown Spectroscopy: An Efficient Tool for Food Science and Technology (from the Analysis of Martian Rocks to the Analysis of Olive Oil, Honey, Milk, and Other Natural Earth Products)

Laser-Induced Breakdown Spectroscopy (LIBS), having reached a level of maturity during the last few years, is generally considered as a very powerful and efficient analytical tool, and it has been proposed for a broad range of applications, extending from space exploration down to terrestrial applications, from cultural heritage to food science and security. Over the last decade, there has been a rapidly growing sub-field concerning the application of LIBS for food analysis, safety, and security, which along with the implementation of machine learning and chemometric algorithms opens new perspectives and possibilities. The present review intends to provide a short overview of the current state-of-the-art research activities concerning the application of LIBS for the analysis of foodstuffs, with the emphasis given to olive oil, honey, and milk.

Pollen analysis of honeys from Apis mellifera and Tetragonisca fiebrigi (Hymenoptera: Apidae) in the Upper Paraná Atlantic Forest, Argentina

Abstract Nectariferous and polliniferous resources are key to the survival of social bees, so identifying the origin sources allows the implementation of management actions aimed at a greater supply of nutrients for the colonies. Besides, defining the floral origin of honeys contributes to their characterization and commercialization. The objective of our work was to identify the plants that provide nectar to the bees Apis mellifera and Tetragonisca fiebrigi in northern Misiones, through palynological analysis of honey samples collected between 2006 and 2008. Both bees showed a polylectic foraging habit. Richness of pollen types per sample ranged between 10 and 34 (mean = 20.5 ± 7.7) for A. mellifera, and between 13 and 43 (mean = 24.8 ± 7.1) for T. fiebrigi. The 15 most abundant pollen types in the honeys of A. mellifera were, in decreasing order of importance, Euphorbiaceae, Euterpe edulis, Holocalyx balansae, Calyptranthes concinna-type, Actinostemon, Salix, Ruprechtia laxiflora, Myrcianthes pungens-type, Thinouia mucronata, Allophylus edulis, Ilex, Syagrus romanzoffiana, Gouania latifolia-type, Parapiptadenia rigida, and Baccharis-type, whereas in the honeys of T. fiebrigi the most important pollen types included S. romanzoffiana, Schinus weinmannifolius-type, Baccharis-type, H. balansae, E. edulis, Rhamnaceae, Citrus, Leonurus japonicus, G. latifolia-type, A. edulis, Gomphrena perennis-type, Pouteria gardneriana, P. rigida, Zanthoxylum, and Actinostemon.

High-throughput method based on a novel thin-film microextraction coating for determining macrolides and lincosamides in honey

A high-throughput method using a new ZIF-8@GO thin-film microextraction coating was established for determining macrolides and lincosamides in honey. The coating preparation parameters (ZIF-8@GO synthesis conditions, coating material proportions, dipping time) and analysis parameters (sample diluent solvent, adsorption and desorption conditions using the ZIF-8@GO coating) were optimized. The optimized parameters were: diluent solvent sodium carbonate/sodium bicarbonate buffer solution (pH 9), adsorption time 45 min, desorption time 5 min, desorption solvent 45:40:15 v/v/v methanol/acetonitrile/water. The extracted targets were determined by ultra-high performance liquid chromatography tandem mass spectrometry. The recoveries of 10 analytes were 67.5-107.2% and the detection and quantification limits were 0.1-0.4 and 0.4-1.4 μg/kg, respectively. The method could analyze 96 samples per run. The minimal manual time and effort is required since the bulk of the sample processing is fully automated. It was a useful and efficient method for monitoring drug residues and was successfully used to analyze real samples.

Classification of Unifloral Honeys from SARDINIA (Italy) by ATR-FTIR Spectroscopy and Random Forest

Nowadays, the mislabeling of honey floral origin is a very common fraudulent practice. The scientific community is intensifying its efforts to provide the bodies responsible for controlling the authenticity of honey with fast and reliable analytical protocols. In this study, the classification of various monofloral honeys from Sardinia, Italy, was attempted by means of ATR-FTIR spectroscopy and random forest. Four different floral origins were considered: strawberry-tree (Arbutus Unedo L.), asphodel (Asphodelus microcarpus), thistle (Galactites tormentosa), and eucalyptus (Eucalyptus calmadulensis). Training a random forest on the infrared spectra allowed achieving an average accuracy of 87% in a cross-validation setting. The identification of the significant wavenumbers revealed the important role played by the region 1540-1175 cm-1 and, to a lesser extent, the region 1700-1600 cm-1. The contribution of the phenolic fraction was identified as the main responsible for this observation.

Fraud in Animal Origin Food Products: Advances in Emerging Spectroscopic Detection Methods over the Past Five Years

Animal origin food products, including fish and seafood, meat and poultry, milk and dairy foods, and other related products play significant roles in human nutrition. However, fraud in this food sector frequently occurs, leading to negative economic impacts on consumers and potential risks to public health and the environment. Therefore, the development of analytical techniques that can rapidly detect fraud and verify the authenticity of such products is of paramount importance. Traditionally, a wide variety of targeted approaches, such as chemical, chromatographic, molecular, and protein-based techniques, among others, have been frequently used to identify animal species, production methods, provenance, and processing of food products. Although these conventional methods are accurate and reliable, they are destructive, time-consuming, and can only be employed at the laboratory scale. On the contrary, alternative methods based mainly on spectroscopy have emerged in recent years as invaluable tools to overcome most of the limitations associated with traditional measurements. The number of scientific studies reporting on various authenticity issues investigated by vibrational spectroscopy, nuclear magnetic resonance, and fluorescence spectroscopy has increased substantially over the past few years, indicating the tremendous potential of these techniques in the fight against food fraud. It is the aim of the present manuscript to review the state-of-the-art research advances since 2015 regarding the use of analytical methods applied to detect fraud in food products of animal origin, with particular attention paid to spectroscopic measurements coupled with chemometric analysis. The opportunities and challenges surrounding the use of spectroscopic techniques and possible future directions will also be discussed.

Eucalyptus honey: Quality parameters, chemical composition and health-promoting properties

Eucalyptus honey is an important unifloral honey commercialized worldwide and much desired by consumers due to the medicinal properties attributed to it because of the plant from which it is produced. In general, eucalyptus honey has been classified as being rich in pollen grains from the eucalyptus tree as well as having physicochemical characteristics that, in a way, have made it stand out from other honeys. Similar to other types of honey, eucalyptus honey can suffer contaminations and adulterations that compromise its quality, safety and authenticity. Thus, detailed knowledge of the composition and properties of this monofloral honeys is of great importance. With this background, the aim of this review is to present and discuss recent data regarding the physicochemical characteristics, chemical and health-promoting properties of eucalyptus honey as well as microbial contamination, authenticity, processing and adulteration.