Comparative study of the physicochemical and palynological characteristics of honey fromMelipona subnitidaandApis mellifera

Comparative analysis of the physicochemical, proximate, and antioxidant characteristics of stingless bee (Meliponula beccarii) honey from modern and wild beehives in Ethiopia

There is a dearth of information on the comparative studies of the physicochemical, proximate, and antioxidant properties as well as quality standards of stingless bee honey (SBH) in Ethiopia. Hence, this study was designed to assess and compare the physicochemical, proximate, and antioxidant properties of SBH, specifically sourced from Meliponula beccarii, and produced under both wild and modern apiary conditions at two distinct geographical locations. A total of forty-six honey samples were meticulously collected from domesticated stingless bee colonies and naturally occurring wild nests at Wolmera and Cheliya districts. Pollen analysis unveiled eleven distinct bee plant species distributed across six families, with Asteraceae being the most prevalent, primarily represented by Guizotia scabra and Vernonia amygdalina. Notably, the physicochemical, proximate, and antioxidant properties of SBH collected from modern pot hives exhibited significant variances (p < .05) when compared to SBH from wild nests. Principal component analysis (PCA) delineated the differentiation of SBH sources based on both geographical location and the type of beehive. One-way ANOVA corroborated these distinctions, underscoring significantly higher levels (p < .05) of ash, electrical conductivity, free acidity, hydroxymethylfurfural, sucrose, total phenolic content, total flavonoid content, and radical scavenging activities of SBH from modern pot hives in Wolmera. Whereas, Cheliya modern pot hives recorded higher values in pH, hydroxymethylfurfural and maltose contents compared to the wild nest SBH. Further analysis through Pearson correlation highlighted a strong positive association between total phenolic content and total flavonoid content with the antioxidant capacity of SBH. These findings underscore the significance of integrating modern pot hives to enhance the quality of SBH within Ethiopia's beekeeping sector.

Study on the non-enzymatic browning of lotus rhizome juice during sterilization mediated by 1,2-dicarboxyl and heterocyclic compounds

BACKGROUND

Lotus rhizome juice (LRJ) is susceptible to the Maillard reaction (MR) and caramelization, which tend to cause a reduction in quality and lower consumer acceptance of the product. 1,2-Dicarbonyl compounds (DCs) and heterocyclic compounds have attracted increasing attention as key intermediates responsible for the formation of brown pigments during MR and caramelization. However, little is known about the effects of these two types of compounds on brown pigments in LRJ during sterilization. This study quantified the changes in brown intensity (A420), DCs, and heterocyclic compounds before and after spiking, and identified the precursors and intermediates for brown pigment formation as well as the formation pathways of the intermediates.

RESULTS

The spiking experiments suggested that spiking with fructose resulted in more 3-deoxyglucosone (3-DG) and 2,3-dihydro-3,5-dihydroxy-6-methyl-4(H)-pyran-4-one (DDMP), while that with lysine led to more glucosone (GS) and 2,3-butanedione (2,3-BD) in LRJ. The addition of glucose, asparagine, and glutamine promoted the formation of 5-hydroxymethylfurfural (HMF) significantly, whereas the addition of glucose, lysine, and asparagine resulted in more norfuraneol. Spiking with reducing sugars and amino acids promoted both glyoxal (GO) and methylglyoxal (MGO), and the effect of glucose on GO was particularly significant. Correlation analysis showed that A420 had the highest correlation with 3-DG in the fructose- and lysine-spiked group, and with HMF in the glucose-, asparagine-, and glutamine-spiked groups.

CONCLUSION

This study revealed that fructose, glucose, asparagine, glutamine, and lysine were essential precursors of MR and caramelization in LRJ during sterilization. 3-Deoxyglucosone and DDMP were mainly produced by caramelization with fructose as the primary precursor, whereas GS and 2,3-BD were primarily formed via MR with lysine catalysis. The MR and caramelization were the main formation pathways of HMF (catalyzed by asparagine and glutamine) and norfuraneol (catalyzed by lysine and asparagine), with glucose as the critical precursor. Methylglyoxal was mainly produced by MR or caramelization, and caramelization was the main formation pathway of GO, with glucose as the precursor. Dor brown pigment formation from fructose and lysine, 3-DG was identified as the most crucial intermediate, while for that from glucose, asparagine, and glutamine, HMF was found to be the most important intermediate. © 2023 Society of Chemical Industry.

The potential neuroprotective effects of stingless bee honey

Tropical Meliponini bees produce stingless bee honey (SBH). Studies have shown beneficial properties, including antibacterial, bacteriostatic, anti-inflammatory, neurotherapeutic, neuroprotective, wound, and sunburn healing capabilities. High phenolic acid and flavonoid concentrations offer SBH its benefits. SBH can include flavonoids, phenolic acids, ascorbic acid, tocopherol, organic acids, amino acids, and protein, depending on its botanical and geographic origins. Ursolic acid, p-coumaric acid, and gallic acid may diminish apoptotic signals in neuronal cells, such as nuclear morphological alterations and DNA fragmentation. Antioxidant activity minimizes reactive oxygen species (ROS) formation and lowers oxidative stress, inhibiting inflammation by decreasing enzymes generated during inflammation. Flavonoids in honey reduce neuroinflammation by decreasing proinflammatory cytokine and free radical production. Phytochemical components in honey, such as luteolin and phenylalanine, may aid neurological problems. A dietary amino acid, phenylalanine, may improve memory by functioning on brain-derived neurotrophic factor (BDNF) pathways. Neurotrophin BDNF binds to its major receptor, TrkB, and stimulates downstream signaling cascades, which are crucial for neurogenesis and synaptic plasticity. Through BDNF, SBH can stimulate synaptic plasticity and synaptogenesis, promoting learning and memory. Moreover, BDNF contributes to the adult brain's lasting structural and functional changes during limbic epileptogenesis by acting through the cognate receptor tyrosine receptor kinase B (TrkB). Given the higher antioxidants activity of SBH than the Apis sp. honey, it may be more therapeutically helpful. There is minimal research on SBH's neuroprotective effects, and the related pathways contribute to it is unclear. More research is needed to elucidate the underlying molecular process of SBH on BDNF/TrkB pathways in producing neuroprotective effects.

Sensory and physicochemical analysis of honeys of nine stingless bee species of Mexico and Guatemala

Honeys produced by species other than Apis mellifera are little known. The objective of this study was to carry out sensory and physicochemical analyses of 62 samples to characterize honeys from nine species of stingless bees from Mexico and Guatemala. Analyses were performed at the sensory level and at the physicochemical level. Qualitative and quantitative data were studied using the multivariate non-metric multidimensional scaling (NMDS) statistical technique, with the Gower metric. According to the stress value (p > 0.2), the most significant parameters were at the sensory level, for visual evaluation, physical state, color, and appearance; for olfactory-taste evaluation, elemental sweet and acid tastes; for tactile evaluation, consistency, and crystallization, and for physicochemical evaluation, pH, electrical conductivity and reducing sugars. Data analysis showed that Melipona beecheii honeys formed a defined group, with similar sensory characteristics and physicochemical values, even taking into account their place of origin. Frieseomelitta nigra honeys also showed significant differences with the other honeys analyzed. Our work suggests that the entomological origin is the main factor that determines the characteristics of honey, and that the floral origin is the secondary factor, a hypothesis that should be verified in future works.

Comparative palynological, physicochemical, antioxidant and antibacterial properties of Romanian honey varieties for biomedical applications

The aim of this study was to investigate the melissopalynology, physicochemical characteristics, antioxidant and antibacterial activity of seven honey samples harvested from different geographical regions and climates of Romania. The melissopalynological analysis revealed that monofloral and multifloral samples contained a wide diversity of minor pollen types from Romanian flora. The moisture, pH and free acidity values were within international limit. HPLC analysis indicated high content of fructose and glucose and low content of sucrose. Bioactive compounds including proteins, phenolics, flavonoids and ascorbic acid were present in variable quantities, according to the botanical origin and geographical area. The highest phenolics and ascorbic acid content was in multifloral honeys from Crisana mountain and meadow and the extrafloral honeydew honey. The same honey samples have exerted free radical scavenging and antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa. The free radical scavenging activity was strongly correlated to phenolics and ascorbic acid content, while the antimicrobial activity was medium correlated only to phenolics content. In conclusion, the selected Romanian honey samples with best antioxidant and antimicrobial activity could be further tested for the development of novel biomedical products.

A Review on Recent Progress of Stingless Bee Honey and Its Hydrogel-Based Compound for Wound Care Management

Stingless bee honey has a distinctive flavor and sour taste compared to Apis mellifera honey. Currently, interest in farming stingless bees is growing among rural residents to meet the high demand for raw honey and honey-based products. Several studies on stingless bee honey have revealed various therapeutic properties for wound healing applications. These include antioxidant, antibacterial, anti-inflammatory, and moisturizing properties related to wound healing. The development of stingless bee honey for wound healing applications, such as incorporation into hydrogels, has attracted researchers worldwide. As a result, the effectiveness of stingless bee honey against wound infections can be improved in the future to optimize healing rates. This paper reviewed the physicochemical and therapeutic properties of stingless bee honey and its efficacy in treating wound infection, as well as the incorporation of stingless bee honey into hydrogels for optimized wound dressing.

Chemical Composition Analysis and Antioxidant Activity of Coffea robusta Monofloral Honeys from Vietnam

Monofloral honey samples (Coffea robusta) from Vietnam were determined for their chemical compositions. This is the first report on the chemical composition and antioxidant activity of coffee honey from Vietnam. These samples were characterized by their high contents of total and reducing sugars, total phenolic contents, and total flavonoid contents. The contents of seven phenolic acids (PAs) were quantified by high performance liquid chromatography (HPLC) and analyzed with the assistance of principle component analysis (PCA) to differentiate the honey samples into groups. The hydroxymethylfurfural (HMF) (0.048–2.933 mg/kg) and free acid contents (20.326–31.163 meq/kg) of coffee honey were lower in Nepal, which reflected the freshness of the honey when conducting this survey. The coffee honey had total sugar and reducing sugar contents 831.711 g/kg and 697.903 g/kg, respectively. The high level of total phenolic (0.642 mg GAE/g) and flavonoid (0.0341 mg GE/g) contents of coffee honey contributed to their antioxidant activity of this honey sample. Among the coffee honey tested, the IC₅₀ of DPPH radical-scavenging activities value was 1.134–17.031 mg/mL, while the IC₅₀ of ABTS radical-scavenging activities value was 115.381–213.769 mg/mL. The phenolic acids composition analysis displayed that gallic acid appeared in high concentrations in all studied honey samples, ranging from 0.037–1.015 mg/kg, and ferulic acid content ranged from 0.193 to 0.276 mg/kg. The content of trigonelline and caffeine in coffee honey samples ranged from 0.314–2.399 mg/kg and 8.946–37.977 mg/kg. The data in this article highlight the relevance of coffee honey as a healthy substance.

Mineral and Botanical Composition of Honey Produced in Chile’s Central-Southern Region

The chemical composition and quality of honey depend on the floral and geographical origin, extraction techniques, and storage, resulting in a unique product for each area. Currently, consumers are not only concerned about the chemical composition, quality, and food safety of honey, but also about its origin. The objective of this study was to characterize honeys produced in Chile’s central-southern region from a mineral and botanical perspective, thus adding value through differentiation by origin. Two hundred honey samples were used and underwent analysis such as melissopalynological composition, nutritional composition, and color. Forty-seven melliferous floral species were identified, out of which 24 correspond to exotic species and 23 to native species. Fifty-six percent were classified as monofloral honeys, 2% as bifloral, and 42% as multifloral. Moisture mean values (17.88%), diastase activity (15.53 DN), hydroxymethylfurfural (2.58 mg/kg), protein (0.35%), and ash (0.25%) comply with the ranges established by both the national and the international legislation; standing out as honeys of great nutritional value, fresh, harvested under optimal maturity conditions, and absence fermentation. Regarding color, light amber was prevalent in most territories. The territory where honey was produced, denoted relevant differences in all the parameters studied.

Ferulic acid as major antioxidant phenolic compound of the Tetragonisca angustula honey collected in Vera Cruz - Itaparica Island, Bahia, Brazil

Abstract The antioxidant activity of Tetragonisca angustula honey (TAH) and its ethanolic extract (TAEE) were investigated. The total levels of phenolic (TPC) and flavonoids (TFC) were also evaluated. The results for TPC were 19.91 ± 0.38 and 29.37 ± 1.82 mg GAE g-1 and for TFC 0.20 ± 0.02 and 0.14 ± 0.01 mg QE g-1 of TAH and TAEE, respectively. Antioxidant activities were 73.29 ± 0.49% and 93.36 ± 0.27% in the DPPH● assay and 71.73 ± 4.07% and 97.86 ± 0.35% in ABTS●+ for TAH and TAEE, respectively. The total reducing activity was determined by the method of reducing power (PR) and iron ion (Fe III) and the results varied in PR from 151.7 ± 25.7 and 230.7 ± 25.2 mg GAE L-1, for TAH and TAEE respectively and for (Fe III) in EC50 0.284 in TAEE and 0.687 in TAH. Chemical analysis by HPLC-DAD of the ethanolic extract (TAEE) revealed the presence of ferulic acid as majority phenolic component in the extract. The 1H NMR analysis confirmed this structure and showed the also presence of glucose, citric acid, succinic acid, proline and hydrocarbon derivatives. In addition, the botanical origin was also investigated and showed a multifloral characteristic, having found 19 pollen types with a botanical predominance of the Anacardiaceae family, with Tapirira pollen occurring as predominant (42.6%) and Schinus as secondary (25.7%). The results showed that T. angustula honey is an interesting source of antioxidant phenolic compounds due to its floral origin and can act as a protector of human health when consumed.

Physical and Rheological Properties of Poly-floral Honey from the Iraqi Kurdistan Region and the Effect of Temperature on its Viscosity

Aims:

In this study, the physical and rheological properties of three poly-floral honey samples collected from different places in the Kurdistan region were determined.

Methods:

The honey samples were analyzed for pH, free acidity, total ash content, moisture content, refractive index, soluble solids (Brix), electrical conductivity, volume expansion, density, specific heat capacity, surface tension, and rheological properties. The pH and free acidity of the honey samples varied from 4.10 to 4.81 to 30 to 62 mEq/kg, respectively. The total ash content ranged from 0.166 to 0.408%. The moisture content, soluble solids, and refractive index ranged from 15.60 to 16.60 g/100 g, 83.40 to 84.40, and 1.4998 to 1.5023, respectively. The electrical conductivity ranged from 40.896 to 44.471 mS/cm. The linear relationship between the electrical conductivity and the ash content was also calculated in this investigation. The volumetric expansion coefficient of the honey samples varied from 6.0098x10-4 to 6.69942x10-4 mm3/K. The density ranged from 1.42125995 to 1.45501137 g/cm3. The specific heat capacity varied from 2448.078 to 2575.004 J/kg.K. The surface tension varied from 0.2178 to 0.2282 N/m. The apparent viscosity was measured by Brookfield Viscometer, and the dynamic viscosity was measured by HAAKE Falling Ball Viscometer, after changing the temperature from 293 to 323 K.

Results and Discussion:

The honey samples of lower moisture content showed a greater increase in their apparent and dynamic viscosities. Arrhenius model was used to describe the effect of temperature on the honey viscosity. This model was used to determine the activation energy. Other rheological properties such as kinematic viscosity and fluidity, were also determined.

Conclusion:

All the honey samples behaved as Newtonian fluids in the whole temperature range.

Monitoring the quality of honey: South African case study

The popularity of honey as a high-valued commodity is growing and consequently, honey adulteration is on the rise affecting the honey quality. The quality of the honey on the South African market was evaluated using the Agricultural Product Standards Act, 1990 as assessment tool. Various physico-chemical characteristics were tested which indicated compliance of >80% for all honey samples. A canonical variate analysis using 95% confidence regions indicates significant differences between the quality of local and imported honey with total acid, sucrose and ash as the parameters mostly distinguishing between the groups. Honey produced from agricultural crops differed significantly from all other forage types. The parameters that mostly distinguished between forage types were Lund, hydroxy-methyl-furfural and ash content. Even though honey sold on the South African market is generally in accordance with national and international standards, an overall declining trend in quality was observed and it should be continuously monitored.

The Toxic Impact of Honey Adulteration: A Review

Honey is characterized as a natural and raw foodstuff that can be consumed not only as a sweetener but also as medicine due to its therapeutic impact on human health. It is prone to adulterants caused by humans that manipulate the quality of honey. Although honey consumption has remarkably increased in the last few years all around the world, the safety of honey is not assessed and monitored regularly. Since the number of consumers of honey adulteration have increased in recent years, their trust and interest in this valuable product has decreased. Honey adulterants are any substances that are added to the pure honey. In this regard, this paper provides a comprehensive and critical review of the different types of adulteration, common sugar adulterants and detection methods, and draws a clear perspective toward the impact of honey adulteration on human health. Adulteration increases the consumer's blood sugar, which can cause diabetes, abdominal weight gain, and obesity, raise the level of blood lipids and can cause high blood pressure. The most common organ affected by honey adulterants is the liver followed by the kidney, heart, and brain, as shown in several in vivo research designs.

Melissopalynological, Physicochemical, Antimicrobial and Microbiological Attributes of Commercial Honeys from North West Nigeria

Background:

Honey is used for nutritional, medicinal and industrial purposes and maintenance of the requisite quality is of great importance.

Objective:

This study distinctively aimed to portray twelve randomly selected profitable honeys accessible in the North West Nigerian market with regards to floral nectar origin, physicochemical factors, antimicrobial activity and microbial safety evaluations.

Methods:

Twelve (12) samples of honey sourced from diverse places in the Northwest of Nigeria were analyzed for their pollen spectra, physicochemical parameters, antimicrobial activity and microbiological safety.

Results:

Dominant pollen types from the analysis were Borassus (72%), Piptadenia africana (39%), Lophira (91%) and Combretaceae (91%) for Sokoto, Jigawa, Kaduna and Katsina States honey samples, respectively. The physicochemical analysis of the samples revealed that pH was in range from 3.32 to 4.25, moisture content varied from 16.37% to 18.70%, ash content 0.23% to 0.93% and free acidity 6.83meq/Kg to 32.00meq/kg, electrical conductivity ranged from 0.13mS/cm to 1.40mS/cm, reducing sugars was 42.85% to 49.30%, sucrose content was 0.74% to 6.75%, Hydroxymethylfurfural value was 11.0mg/Kg to 80.20mg/Kg, diastase level ranged from 7.23 to 43.5 and Proline content ranged from 104.67mg/Kg to 666.67mg/Kg. The antimicrobial evaluation revealed significant zone of inhibition to E. coli, ranging from 19-38 mm at concentrations (12.5-100mg/mL) tested as compared to all other test organisms.

Conclusion:

The fallouts of microbiological investigation of the samples revealed mould and bacteria, with counts less than 102CFU/g. The findings showed that the attributes of the tested honey samples maintained criteria of international standards.

Honey from Tiúba stingless bees (Melipona fasciculata) produced in different ecosystems: physical and sensory studies

BACKGROUND

Honey from Tiúba stingless bees (Melipona fasciculata) produced in three different ecosystems in Brazil (Cerrado, Litoral and Baixada), as well as a sample of honey from Apis mellifera bees from the Baixada region for comparison, were evaluated regarding viscosity, color, sensory profile and sensory acceptance.

RESULTS

The honey from Tiúba was less viscous, with a darker color and lower purity of the color (chroma) in relation to honey from Apis mellifera. The sensory profile firmly differentiates the honeys. The Apis honey was mainly described as opaque, viscous and adhesive. Tiúba honey from the Cerrado region stood out as semi-bright, acid taste, alcoholic, propolis, bitter taste and spicy. Tiúba honey from the Litoral region was characterized by its yellow color, woody odor and medicine flavor. The Tiúba honey from the Baixada region was described as gold colored, fluid and citric. The Tiúba honey from the Cerrado region had similar sensory acceptance to the Apis honey, probably because it was specifically characterized through attributes of odor and flavor. On the contrary, the Tiúba honey from the Litoral and from the Baixada regions was less well accepted.

CONCLUSION

The honeys are different regarding their physical and sensory properties, differences that result from the bee species and from the geographical origin of the honey. This study could contribute to the creation of a standard identity and specific quality for Melipona fasciculata honey, also contributing to its production and commercialization not only in Brazil, but also internationally. © 2020 Society of Chemical Industry.

Quality evaluation of Saudi honey harvested from the Asir province by using high-performance liquid chromatography (HPLC)

Sugar profile and hydroxymethylfurfural (HMF) of Saudi honey were examined through high-performance liquid chromatography (HPLC) system equipped with refractive index and diode array detectors. The work was designed to assess the quality of various types of blossom honey i.e. Sider (Ziziphus spina-christi), Dhuhyana (Acacia asak), Sumra (Acacia tortilis), Qatada (Acacia hamulosa), Dhurum (Lavandula dentata), multiflora with majra (Hypoestes forskaolii), multiflora with herbs, Keena (Eucalyptus spp.) produced in the southwestern areas of the kingdom. Hierarchical cluster analysis (HCA), principal cluster analysis (PCA), and similarity and difference indices (SDI) were also applied to examine the possible grouping based on the studied quality parameters. Four main sugars (two monosaccharides i.e. fructose and glucose, two disaccharides i.e. sucrose and maltose) and HMF were investigated . The average values of fructose and glucose were in the range 33.10%–44.77% and 26.68%–37.91%, respectively. The maltose was present in all types of honey and its mean values were in the range of 0.37%–2.97%, while sucrose was absent in six types of honey, 0.25% in one unifloral honey, and 3.25% in one multi-floral honey. HMF was not detected in seven types of honey but was below the limit of quantification (0.13 mg/kg) in one type of honey. PCA displayed the accumulative variance of 79.96% for the initial two PCs suggesting that honey samples were not well distinguished by their sugar profile. Based on the sucrose and HMF contents, it was concluded that all types of blossom honey from the Asir province were of the best quality in the kingdom and met the international quality parameters.

Authentication of honeys from Caramulo region (Portugal): Pollen spectrum, physicochemical characteristics, mineral content, and phenolic profile

This study aimed to analyze the botanical origin, quality parameters, phenolic compounds, and minerals of 20 honey samples from Caramulo region (Portugal). Six samples were monofloral from Eucalyptus sp., being this one the predominant pollen in the analyzed samples, followed by Castanea sativa. The average values obtained for the physicochemical parameters were as follows: 4.7 pH; 16.8% moisture; 81.4 Brix; 0.3% ash; 512.8 µS/cm electrical conductivity; 22.6 meq/kg free acidity; 12.4 meq/kg lactonic acidity; 35.1 meq/kg total acidity; 2.1 mg/kg hydroxymethylfurfural; and 16.3 °Gothe for diastase activities. A total of 18 phenolics were determined by high-performance liquid chromatography-diode array detector. Hydroxycinnamic acid derivatives and protocatechuic acid were the major ones. Nine minerals were detected by atomic absorption spectrometry; potassium and phosphorus were the predominant mineral elements. This is the first study about honeys from Caramulo region, which revealed to have a good quality and be a rich source of essential minerals and phenolics. PRACTICAL APPLICATION: The interest in the analysis of honey has increased significantly in recent years, concerning its characterization, safety implications, and health impact. Given these facts, the authentication of honeys, based on the geographical and botanical origins, has been assuming great importance, being mainly associated with high-quality honeys. Therefore, we decided to analyze physicochemical parameters, phenolic composition, and mineral content of 20 Caramulo honey samples. Our results indicate that Caramulo honeys possess high-quality levels, good freshness, maturity, and proper processing, and are also rich in several bioactive substances with health-promoting properties, including phenolic compounds, potassium, and phosphorus.

Pathway of 5-hydroxymethyl-2-furaldehyde formation in honey

5-hydroxymethyl-2-furaldehyde (5-HMF) is an important substance that affect quality of honey and shows toxicity for humans and honey bees. The pathway of 5-HMF formation in honey is still unknown. In this study, we tested the effect of thermal treatment (at 90 °C for 4 h) on the formulation of 5-HMF formulation in rapeseed with varied honey composition. 5-HMF content of honey increased at higher water content, Ca²⁺ and Mg²⁺ content and lower pH. However, the formation of 5-HMF was not significantly influenced by glucose, fructose, Na⁺, or K⁺ contents. Furthermore, different content of proline, the most abundant amino acid in honey (a substance in Maillard reaction), had no effect on 5-HMF formation. Free acids in honey can catalyze fructose and glucose to form 5-HMF. These results suggest that dehydration of glucose or fructose, instead of the Maillard reaction, is the main pathway of 5-HMF formation in honey. This study gives new insights for the mechanisms of 5-HMF formation and provides method for reducing 5-HMF formation during honey processing.

An overview of physicochemical characteristics and health-promoting properties of honeydew honey

Honeydew honey has differentiated chemical and physicochemical characteristics besides potential functional properties such as antimicrobial, anti-inflammatory and antioxidant. In this sense, the interest and consumption of this honey as a functional product by the food industry and consumers have increased. Honeydew honeys usually present dark color, a lower content of monosaccharides and higher values of pH, acidity, electric conductivity, proteins, minerals, phenolic compounds, and oligosaccharides compared to blossom honeys, which contribute to its outstanding biological activities. Consequently, contaminations and adulterations of this honey can occur and compromise the quality, safety and authenticity of honeydew honey. Thus, detailed knowledge of the composition and properties of honeydew honeys is of great importance, especially considering that honeydew honeys are still few studied and therefore underestimated. Therefore, in this review, the physicochemical characteristics, chemical and bioactive composition, functional and health-promoting properties of honeydew honey as well as contamination, adulteration and authenticity of this honey are summarized.

Honey Evaluation Using Electronic Tongues: An Overview

Honey-rich composition in biologically active compounds makes honey a food products highly appreciated due to the nutritional and healthy properties. Food-manufacturing is very prone to different types of adulterations and fraudulent labelling making it urgent to establish accurate, fast and cost-effective analytical techniques for honey assessment. In addition to the classical techniques (e.g., physicochemical analysis, microscopy, chromatography, immunoassay, DNA metabarcoding, spectroscopy), electrochemical based-sensor devices have arisen as reliable and green techniques for food analysis including honey evaluation, allowing in-situ and on-line assessment, being a user-friendly procedure not requiring high technical expertise. In this work, the use of electronic tongues, also known as taste sensor devices, for honey authenticity and assessment is reviewed. Also, the versatility of electronic tongues to qualitative (e.g., botanical and/or geographical origin assessment as well as detection of adulteration) and quantitative (e.g., assessment of adulterants levels, determination of flavonoids levels or antibiotics and insecticides residues, flavonoids) honey analysis is shown. The review is mainly focused on the research outputs reported during the last decade aiming to demonstrate the potentialities of potentiometric and voltammetric multi-sensor devices, pointing out their main advantages and present and future challenges for becoming a practical quality analytical tool at industrial and commercial levels.

Effects of honey fromMimosa quadrivalvisL. (malícia) produced by theMelipona subnitidaD. (jandaíra) stingless bee on dyslipidaemic rats

The supplementation with malícia honey alters the lipid metabolism, antioxidant status and intestinal health parameters of rats with diet-induced dyslipidaemia.

Influence of Botanical Origin and Chemical Composition on the Protective Effect against Oxidative Damage and the Capacity to Reduce In Vitro Bacterial Biofilms of Monofloral Honeys from the Andean Region of Ecuador

Three types of monofloral honey from the Andean regions of Ecuador (Avocado, Eucalyptus, and Rapeseed honey) were analyzed to determine their floral origin, physicochemical parameters, chemical composition, antioxidant capacity, and their capacity to reduce in vitro bacterial biofilms. The chemical composition varied considerably depending on floral origin. The highest values of bioactive compounds were found in Avocado honey, classified as dark amber in color, while the lowest values were found in Eucalyptus honey followed by Rapeseed honey, both classified as extra light amber. When compared to Eucalyptus and Rapeseed honey, Avocado honey showed a more effective superoxide scavenging activity, chelating metal ions capacity, and a higher ability to protect human erythrocyte membranes against lipid peroxidation. For antimicrobial activity, the hydrogen peroxide content and the capacity to inhibit the biofilm formation, and to remove preformed biofilm from Staphylococcus aureus and Klebsiella pneumoniae was determined. Avocado honey showed the highest values of hydrogen peroxide content, as well as the highest capacity to reduce in vitro bacterial biofilms. A correlation between color vs. phenolics content vs. superoxide scavenging activity vs. chelating metal ions capacity, and the capacity to protect human erythrocyte membranes against lipid peroxidation was found.

How soil type (gypsum or limestone) influences the properties and composition of thyme honey

BACKGROUND AND AIMS

The objective of this work was to determine the influence of the soil substrate on the characteristics and properties of a specific type of honey. As such, we analysed the features of a typical single-flower honey, thyme honey, produced in a specific Mediterranean region. Thymus is a genus of aromatic perennial plants that are native to Europe, North Africa and Asia.

METHODS

A total of 70 honey samples from hives situated on limestone (38 samples) or gypsum soils (32 samples) were studied. The physical and chemical properties of each samples were analyzed using standard assays.

RESULTS

Within the same geographical area and despite a similar thyme pollen content, we observed variation in the physicochemical, antioxidant and sensorial characteristics of monofloral honeys. The quantification of certain physicochemical parameters of the honey indicated these features were influenced by the soil type. Indeed, the soil type of the hives' settlement area, limestone or gypsum, influences the conductivity, antioxidant capacity, colour and floristic composition.

CONCLUSIONS

The present work demonstrates that soil type (gypsum or limestone) influences the characteristics of honey, potentially providing added market value to these products.

Nutritional and mineral contents of honey extracted by centrifugation and pressed processes

In this study, wild honey samples extracted by two different methods (centrifugation and pressed processing) were characterized and compared based on their physicochemical, and nutritional properties, macro- and micro-mineral contents, and pollen counts. Twelve colonies of Africanized Apis mellifera were used; six honey samples were obtained by centrifugation and six by honeycomb press. All physicochemical parameters of honey samples (moisture, pH, total acidity, ash, dry matter, and qualitative absence of hydroxymethylfurfural) were within the limits established by EU legislation, and all parameters in pressed honey were superior (p<0.05). Nutritional contents (total carbohydrates, total lipids, total proteins, flavonoids, and ascorbic acid) and minerals (K, Ca, Mg, Na, Fe, Li, Zn) were also higher in pressed honey. The quantity of pollen in pressed honey samples was 5.6-fold higher than in centrifuged samples. Pressed honey, can be marked as a differentiated product with a higher mineral content and several nutritional properties.

Microbiological and physicochemical analysis of yateí (Tetragonisca angustula) honey for assessing quality standards and commercialization

Due to the interest in the production and trading of yateí (Tetragonisca angustula) honey in the province of Misiones, Argentina, in this work we assessed microbiological and physicochemical parameters in order to contribute to the elaboration of standards for quality control and promote commercialization. Results showed that yateí honey samples had significantly different microbiological and physicochemical characteristics in comparison to established quality standards for Apis mellifera honey. Thus, we observed that values for pH (3.72), glucose (19.01 g/100g) and fructose (23.74 g/100g) were lower than A. mellifera quality standards, while acidity (79.42 meq/kg), moisture (24%), and mould and yeast count (MY) (3.02 log CFU/g) were higher. The acid content was correlated with glucose (R2=0.75) and fructose (R2=0.68) content, and also with mould and yeast counts (R2=0.45) to a lesser extent. The incidence of microorganisms in yateí honey samples reached 42.85% and 39% for Clostridium sulfite-reducers and Bacillus spp., respectively. No C. botulinum or B. cereus cells were detected. Enterococcus spp. and Staphylococcus spp. incidence was similar (ca. 7.14%), whereas Escherichia coli and Salmonella spp. were not detected. We conclude that the microbiological and physicochemical properties of yateí honey are different from those of A. mellifera honey; hence, different quality standards could be implemented to promote its commercialization.

A Study on the Quality and Identity of Brazilian Pampa Biome Honey: Evidences for Its Beneficial Effects against Oxidative Stress and Hyperglycemia

We characterized, for the first time, the quality and identity of Brazilian Pampa biome honey and its antioxidant properties in vitro (FRAP, DDPH and ABTS). The potential protective effect of honey against oxidative stress induced by iron (Fe) and paraquat, (PQ) in a Drosophila melanogaster model (in vivo) was also tested. The results indicated that all honey samples tested showed antioxidant activity in vitro. Flies treated with honey showed increased lifespan and were protected against oxidative stress induced by Fe and PQ. Despite the high concentration of sugars in honey (approximately 70–80%), our results demonstrate a hypoglycemic-like effect of honey in Drosophila. Thus, this study demonstrates the high quality of Brazilian Pampa biome honey as well as its significant antioxidant activity in vitro and in vivo, pointing to the potential use of this natural product as an alternative in the therapy of oxidative stress-associated diseases.