Search

Quantum chemical methods have been intensively applied to study the pyrolytic conversion of glucose into hydroxymethylfurfural (HMF) and furfural (FF). Herein, we collect the most relevant mechanistic proposals from the recent literature and organize them into a single reaction network. All the transition structures (TSs) and intermediates are characterized using highly accurate ab initio methods and the possible reaction pathways are assessed in terms of the Gibbs energies of the TSs and intermediates with respect to β‐glucopyranose, selecting a 2D ideal‐gas standard state at 773 K to represent the pyrolysis conditions. Several pathways can lead to the formation of both HMF and FF passing through rate‐determining TSs that have ΔG‡ values of ~49–50 kcal/mol. Both water‐assisted mechanisms and nonspecific environmental effects have a minor impact on the Gibbs energy profiles. We find that the HMF → FF + CH2O fragmentation has a small ΔrxnG value and an accessible ΔG‡ barrier. Our computational results, which are in consonance with the kinetic parameters derived from lumped models, the results of isotopic labeling experiments and the reported HMF/FF molecular ratios, could be useful for modeling studies including on nonequilibrium kinetic effects that may render more information about product yields and the relevance of the various pathways. [ABSTRACT FROM AUTHOR]

ABSTRACT Acrylamide (AA) and 5‐hydroxymethylfurfural (HMF) are the byproducts of the Maillard reaction that pose health risks due to their high exposure to the Western diet. Current study examines the impact of yeast fermentation on AA, HMF formation, and chemical composition of French fries. Fermentation, known for enriching food with beneficial probiotics, vitamins, and minerals, is coupled with blanching, a technique used to inactivate enzymes and reduce microbial load, thus preserving color and extending shelf life. Fermentation reduced HMF and AA levels in French fries by approximately 86.5% and 54.78%, respectively. Furthermore, combining fermentation with blanching treatment further decreased HMF and AA levels by 88.62% and 59.81%, respectively. This research suggests that yeast fermentation, particularly when combined with blanching treatment, can effectively mitigate the formation of AA and HMF in French fries, thereby potentially reducing their health risks. This pioneering research opens avenues for additional inquiries, laying the groundwork for future advancements in enhancing food safety. [ABSTRACT FROM AUTHOR]

This study aims to develop a thin-film nanofibrous composite (TFNC) membrane for removing fermentation inhibitors from a hydrolysate solution. Such membrane was fabricated via interfacial polymerization of a polyamide thin-film layer on top of a solution blow-spun polyacrylonitrile nanofiber scaffold. The effects of pH (3.29, 4.29, 8.26) and pressure (4, 6.67, 9.33, 12 bar) on the membrane's performance were investigated. The TFNC membrane had a high pure water permeability of 21.06 L/m2-h-bar and was able to deliver satisfactory rejection coefficients at pH 3.29 and pressure of 4 bar (glucose − 91.84%, xylose − 86.06%, hydroxymethylfurfural − 20.52%, furfural − 21.32%). Different pH settings resulted in similar permeate fluxes, but increasing the pH from acidic to basic reduced the rejection coefficients due to electrostatic repulsion. Increasing the pressure increased the permeate flux but decreased the rejection coefficients. The developed membrane showed remarkable permeability and effectively removed inhibitors, useful in biorefineries. [ABSTRACT FROM AUTHOR]

This study presents a novel approach for producing xylitol from xylose‐rich hydrolysate derived from pistachio shells. Initially, xylose‐rich hydrolysate was obtained through microwave‐assisted high‐pressure CO2/H2O hydrolysis, achieving a maximum xylose concentration of 14.58 ± 0.11 g L−1 and yield of 62.01 ± 0.92% (w w−1). Prior to the bioconversion process, the hydrolysate was detoxified using activated charcoal to remove inhibitory compounds such as hydroxymethylfurfural (HMF) and furfural. Xylitol production from the detoxified hydrolysate was carried out biotechnologically using the yeast Candida tropicalis. A Box–Behnken design was implemented to investigate the effect of temperature, pH, and aeration rate on xylitol yield during bioconversion in bioreactor. The highest xylitol yield of 0.94 g g−1 was recorded at 72 h under optimized conditions of 34.5 °C, pH 4.5, and 1.2 vvm. Recovery and purification of xylitol from the fermentation medium was achieved using ethanol as an antisolvent. Xylitol was recovered with a yield of 68.4% from culture medium by crystallization. Based on the findings of this study, a sustainable and environmentally friendly process can be proposed for recovering and purifying xylitol from pistachio shell hydrolysate. [ABSTRACT FROM AUTHOR]

The development of platform chemicals derived from biomass, in particular, 5‐hydroxymethylfurfural (5‐HMF) and furfural (FUR), is of crucial importance in biorefinery. Over the past decades, metal‐supported nanostructured zeolites, in particular, metal‐supported hierarchically porous zeolites or metal‐encapsulated zeolites, have been extensively elaborated because of their multiple functionalities and superior properties, for example, shape‐selectivity, (hydro)thermal stability, tunable acidity and basicity, redox properties, improved diffusion, and intimacy of multiple active sites. In this review, the effects of such properties of metal‐supported nanostructured zeolites on the enhanced catalytic performances in furanic compound upgrading are discussed. In addition, the recent rational design of metal‐supported nanostructured zeolites is exemplified. Consequently, the ongoing challenges for further developing metal‐supported nanostructured zeolites‐based catalysts and their applications in HMF and FUR upgrading are identified. [ABSTRACT FROM AUTHOR]

The Melipona fasciculata is a stingless bee and her honey has properties and flavor appreciated by different consumers. Its production provides a source of income for poor communities in Maranhão, Brazil. However, the absence of Brazilian legislation for this type of honey, as it exists for Apis mellifera, prevents the expansion of the commercialization of M. fasciculata honey. This study was carried out to identify microbiological and physicochemical patterns of honey in seven important locations in the Baixada Maranhense, in the north of Brazil. The honeys showed good hygienic-sanitary quality, in line with Brazilian legislation for A. mellifera honey and the proposal for regulation of stingless bee (SLB) honey. However, 16% of samples belonging to five locations showed contamination by mesophilic bacteria. The physicochemical parameters were variable, mainly moisture indexes (%), with means between 19.35 to 21.22. The HMF content of São Bento (70.70 mg.kg−1) was above current Brazilian legislation. Total acidity showed higher averages in half of São Bento, Viana and Palmeirândia when compared to legislation and the SLB (Max: 50 mEq.kg−1). As for the principal component analysis, HMF and TA showed a positive correlation. With regards to reducing sugar content, only the mean in Peri-Mirim city reached values registered with the Apis legislation and the proposed SLB. In general, the honeys in this study showed rates compatible with those of other SLB, however, in disagreement with parameters required by the Brazilian regulation of Apis, motivating the establishment of specific legislation for honey in Maranhão. [ABSTRACT FROM AUTHOR]

We carried out a mechanistic investigation of the dehydration of fructose catalyzed by a series of proton‐exchanged faujasite zeolites. Using a combination of analytical tools (HPLC, GC, NMR), we could solve and quantify most of the variety of products formed, including (i) cyclic intermediates (ii) transient species (monomeric and dimeric) (iii) byproducts (oligomeric species and humins). The results prove that the reaction goes through a cyclic mechanism, and we could propose a kinetic model matching most of our experimental results and describing the interplay between the different categories of products. By comparing the performances of different catalysts with varying properties, we surprisingly find that increasing the concentration of Brønsted acid sites induces lower catalytic activity. Contrary to general expectations, the mesoporous volume seems to be the most determining parameter for the activity of the catalysts over the set of catalysts evaluated here, which may be explained by the importance of allowing the reactant a significant accessibility to the active sites. [ABSTRACT FROM AUTHOR]

5‐Hydroxymethylfurfural (5‐HMF) is an important biomass‐based platform compound that links biomass feedstocks with petrochemical refinery products. In this work, we developed a novel approach using triethylbenzylammonium chloride (TEBAC)‐based acidic deep eutectic solvents (ADESs) to synthesize 5‐HMF through the dehydration of fructose. Our approach demonstrates significant improvements in both 5‐HMF yield and process efficiency compared to conventional solvent systems. Under optimal experimental conditions (90 °C, 4.5 h), a maximum 5‐HMF yield of 97.77±3.20 % was achieved at a TEBAC:acetic acid ratio of 2 : 3 with 1 wt % fructose loading, which represents a notable advancement over other methods. Notably, our system inhibits the formation of by‐products such as levulinic acid (LA) and formic acid (FA), which are commonly detected in other dehydration processes. Additionally, higher 5‐HMF yields of 76.67±0.33 % and 73.51±1.14 % were achieved with 10 wt % and 20 wt % fructose loadings, respectively, further highlighting the scalability of the process. The acidity of ADESs was found to significantly affect the dehydration rate and yield, as demonstrated through Hammett's acidity function analysis. The key innovation of our study lies in the strategic selection of hydrogen bond donors and acceptors in the DES, enabling both high efficiency and selectivity in 5‐HMF production. These findings provide a promising pathway for large‐scale biomass conversion with reduced by‐product formation. [ABSTRACT FROM AUTHOR]

Honey is known for its high nutritional value and is used both as a sweetener and as a medicine. However, owing to high demand and low supply, honey adulteration has become a global concern. Hydroxymethylfurfural (HMF) is an important quality indicator that exists in trace amounts but accounts for a significant portion of the sugar content in honey. According to the International Honey Commission and Codex Alimentarius Commission of the World Health Organization, Food and Agriculture Organization, and European Union, HMF levels ≥ 40 mg/kg (≥ 80 mg/kg in tropical countries) are considered harmful to humans. This review investigated the levels of HMF in commercial acacia honey from various countries worldwide. I selected 28 studies reporting on acacia honey, the utilization of HMF as a quality indicator, range and mean values for HMF, mean values for reducing sugar (total fructose and glucose), and acidity and moisture results. Most studies reported that the levels of HMF and other important factors were within the legal limit—only a few samples in four of the 28 studies had HMF levels higher than the legal limit. In conclusion, current evidence indicates that commercial acacia honey undergoes limited adulteration and maintains a high quality, in accordance with regulatory guidelines. It is necessary to maintain honey quality during harvest and storage.Article Highlights: Hydroxymethylfurfural is a key quality parameter for commercial Acacia honey sold worldwide Most studies report good quality honey products, based on various factors Storge time, conditions, and adulteration are important drivers of HMF content [ABSTRACT FROM AUTHOR]

Abstract Honey is known for its high nutritional value and is used both as a sweetener and as a medicine. However, owing to high demand and low supply, honey adulteration has become a global concern. Hydroxymethylfurfural (HMF) is an important quality indicator that exists in trace amounts but accounts for a significant portion of the sugar content in honey. According to the International Honey Commission and Codex Alimentarius Commission of the World Health Organization, Food and Agriculture Organization, and European Union, HMF levels ≥ 40 mg/kg (≥ 80 mg/kg in tropical countries) are considered harmful to humans. This review investigated the levels of HMF in commercial acacia honey from various countries worldwide. I selected 28 studies reporting on acacia honey, the utilization of HMF as a quality indicator, range and mean values for HMF, mean values for reducing sugar (total fructose and glucose), and acidity and moisture results. Most studies reported that the levels of HMF and other important factors were within the legal limit—only a few samples in four of the 28 studies had HMF levels higher than the legal limit. In conclusion, current evidence indicates that commercial acacia honey undergoes limited adulteration and maintains a high quality, in accordance with regulatory guidelines. It is necessary to maintain honey quality during harvest and storage.

The compound 5-(hydroxymethyl)furfural (HMF) has emerged as a versatile intermediate with the ability to undergo conversion into both fuel and a variety of platform chemicals. Lignocellulosic biomass, such as hazelnut shells and tea processing residues, was employed in this study for HMF production through two distinct methods. In the first method, cellulose from biomass was converted to sugars using a 4% acid solution, followed by catalytic conversion with NaCl/CrCl3.6H2O. After a 1-h reaction at 131 °C in a high-pressure system, HMF was obtained from tea processing waste and hazelnut shells with yields of 8.6% (82.3 mg/g) and 6.7% (66.7 mg/g), respectively. The second method involved LiCl/NaCl-doped N,N-dimethylacetamide (DMA) as an ionic solvent system for HMF production. After a 2-h reaction at 131 °C in the DMA-NaCl/[EMIM]Cl ionic solvent system, HMF was obtained from tea processing waste and hazelnut shell celluloses with yields of 5.7% (57.5 mg/g) and 3.1% (31.3 mg/g), respectively. This study contributes to the economic conversion of various food wastes into valuable chemicals, highlighting the potential of lignocellulosic biomass in sustainable chemical production.

Natural honey can change its physicochemical and biological properties during storage. According to State Standard 19792-2017, honey should be stored at ≤ 20°C. Some publications promote long-term storage of honey at temperatures between 0 and –20°C that preserves its physicochemical parameters, especially the content of hydroxymethylfurfural. Promising as they seem, such temperature modes may affect other physicochemical parameters of honey. The research objective was to study the effect of different temperature conditions on various honey samples and their physicochemical and biological parameters during long-term storage. The study applied standard and authentic research methods to fresh linden, buckwheat, and sunflower honey samples obtained from Rostov, Volgograd, Kursk, Voronezh, Saratov, and Krasnodar regions. They were stored in heat, cold, and moisture test chambers M-60/100-500 for 12 months. Hydroxymethylfurfural proved stable at –18°C for 12 months. After 12 months at 18°C, it showed a sharp increase of 472.5–488.1%. The activity of enzymic diastase, D-glucose-1-oxidase, and catalase occurred at all temperature modes after 1 month of storage. At 0–5°C, the changes were minimal: hydrogen peroxide (H2O2) remained stable, and its concentration decreased by ≤ 12.2% after 12 months of storage. Moisture, mass fraction of reducing sugars, and acidity remained stable in all samples. An antimicrobial test by Escherichia coli (strain 1257), Staphylococcus aureus (strain 209-P), and Bacillus cereus (strain 96) showed that the best inhibiting properties belonged to the samples of linden and buckwheat honey stored at 5 and 0°C for 12 months. The optimal temperatures for long-term honey storage were in the range between 5 and 0°C. The results obtained can be used in updated honey storage standards.

Development of elegant, selective, and efficient strategies for the production of value‐added platform chemicals from renewable feedstocks are in high demand to achieve the future needs and sustainable goals. In this context, an efficient acid‐promoted synthesis of highly valuable hydroxymethylfurfural (HMF) has been demonstrated from glucose, a major constituent of lignocellulosic biomass. The major challenge in the conversion of glucose to HMF is the selective isomerization of glucose to ketose, which in the present work has been successfully addressed through the amine‐mediated rearrangement of glucose to aminofructose under Amadori rearrangement. Importantly, subsequent dehydration step affords HMF and regenerates the amine employed in the first step, which could be readily recovered. In addition, scale‐up and successful integration into one‐pot synthesis of HMF proves the efficiency and applicability of the present transformation in large scale application. In addition, the method was also successfully extended to other monosaccharides and disaccharides to produce HMF. [ABSTRACT FROM AUTHOR]

Converting carbohydrates into 5-hydroxymethylfurfural (5-HMF) is an attractive and promising route for value-added utilization of agricultural and forestry biomass resource. As an important platform compound, 5-HMF possesses high active furan structure with hydroxymethyl and aldehyde group for production of various bio-chemicals and materials, meanwhile, which suffer from low stability and poor yield during the industrial biorefinery process. Hence, selective production of 5-HMF with high-yield and low-cost has attracted extensive attention from scientific and industrial researchers. This review sorted and described the latest advanced research on solvent and catalyst system, as well as energy field effect for production of 5-HMF with different feedstock in detail, emphatically discussing the solvent effect and its synergistic effect with other aspects. Besides, the future prospects and challenges for production of 5-HMF from carbohydrates were also presented, which provide a profound insight into industrial 5-HMF process with economic and environmental feature. [ABSTRACT FROM AUTHOR]

The reaction steps involved in the 5‐hydroxymethylfurfural to 2,5‐furandicarboxylic acid conversion by means of H2O2 were investigated employing a dedicated computational protocol based on density functional theory. The catalytic environment of choice was a molecular model representing a portion of the halloysite nanotube outer surface, functionalized by an organosilane, the 3‐aminopropyltriethoxysilane, whose amino group bonds one gold atom. At this stage of the investigation, the process was fully detailed in terms of the interactions between the reaction intermediates and the catalyst, and the reaction standard free energies. In addition, the energy barriers of the elementary steps involving the hydrogen migration from the adsorbed organic species to the gold atom were analyzed. On the basis of the interaction geometries, a certain distinction among the preferred reaction path can be inferred as a function of the net negative charge characterizing the catalyst outer surface. Since the inner surface of halloysite can represent the acid environment needed to obtain 5‐hydroxymethylfurfural through dehydration of fructose, the present study is framed in a wider research field where the possibility to consider functionalized halloysite as one‐pot reactor for the valorization of biomass is explored. [ABSTRACT FROM AUTHOR]

Rapid, efficient, versatile, easy-to-use, and non-expensive analytical approaches are globally demanded for food analysis. Many ambient ionization approaches based on electrospray ionization (ESI) have been developed recently for the rapid molecular characterization of food products. However, those approaches mainly suffer from insufficient signal duration for comprehensive chemical characterization by tandem MS analysis. Here, a commercially available disposable gel loading tip is used as a low-cost emitter for the direct ionization of untreated food samples. The most important advantages of our approach include high stability, and durability of the signal (> 10 min), low cost (ca. 0.1 USD per run), low sample and solvent consumption, prevention of tip clogging and discharge, operational simplicity, and potential for automation. Quantitative analysis of sulfapyridine, HMF (hydroxymethylfurfural), and chloramphenicol in real sample shows the limit-of-detection 0.1 μg mL−1, 0.005 μg mL−1, 0.01 μg mL−1; the linearity range 0.1–5 μg mL−1, 0.005–0.25 μg mL−1, 0.01–1 μg mL−1; and the linear fits R2 ≥ 0.980, 0.991, 0.986. Moreover, we show that tip-ESI can also afford sequential molecular ionization of untreated viscous samples, which is difficult to achieve by conventional ESI. We conclude that tip-ESI–MS is a versatile analytical approach for the rapid chemical analysis of untreated food samples. [ABSTRACT FROM AUTHOR]

Honey was reported numerous benefit containing nutritional ingredients and phytochemical such as polyphenol, flavonoid was widely used around the world. In this study, the physicochemical characteristics on the quality of coffee flower honey has been evaluated during storage. The honey was collected from Dak Lak, Buon Me Thuot, and Kon Tum province in Vietnam and stored at room temperature (30 -32°C) for 12 month. Total sugar, reducing sugar, hydroxymethylfurfural (HMF), acid value, total polyphenol content (TPC) and total flavonoid content (TFC) were evaluated for each two month to determine the quality of sensory quality and nutritional value. After 12 month storage time, the content of total sugar, and reducing sugar gradually decreased along with the increase of HMF and acid content in the coffee flower honey samples a lead to sweetness of honey is decrease, acidity, and color increase, which is a signal indicating a decline in sensory quality and nutritional value. The content of TPC and TFC increased during the first 6 -10 months of storage and then also tended to decrease, indicating that coffee flower honey should not be stored for too long (more than 10 months) because of phytochemicals reducing. [ABSTRACT FROM AUTHOR]

This in vitro and in silico study was designed to validate acclaimed anti-inflammatory or pain-relieving properties of fermented ethnic beverages prepared from Rhododendron or Guras flowers in the Singalila ridge- the famous Rhododendron growing region of the Himalayas. Traditional beverages Guras wine and its distilled version Guras Raksi were considered in this study which were collected from Gairibas, a village situated in Indo-Nepal Singalila Ridge of the Himalayas. In vitro protein (albumin) denaturation inhibition assay was conducted to evaluate anti-inflammatory activity of the samples and later GC-MS analysis was carried out to identify anti-inflammatory compounds present in those beverages. From GC-MS results, eleven major metabolites such as 5-hydroxymethylfurfural; quinic acid; clionasterol; l-(+)-ascorbic acid, 2,6-dihexadecanoate; d-sorbitol; cis-cinnamic acid; tyrosol; lupeol; methyl commate A; 2-hydroxy-gamma-butyrolactone; and 1,3-propanediol, 2-(hydroxymethyl)- 2-nitro- were chosen for molecular docking with human cyclooxygenase-1 (hCOX-1), an important targets in the drug-design for nonsteroidal anti-inflammatory drugs. Among all query compounds, phytosterol- clionasterol and triterpenoid- lupeol and methyl commate A exhibited considerably high binding energy scores (<-8 kcal/mol) even compared to anti-inflammatory drugs- acetaminophen and ibuprofen. Outcome of this research affirmed the potential of Gurasbased traditional drinks in the healing of different forms of high-altitudinal stress induced pain. [ABSTRACT FROM AUTHOR]

Natural bee honey can change its physicochemical and biological properties during storage. Literature data on long-term storage of honey at low temperatures (from 0 to -20 °C) indicate that this ensures the stability of some physicochemical parameters. Despite the potential benefits of these temperature regimes for practical use, it is important to consider their potential negative effects on honey quality. The aim of this study was to investigate the influence of various temperature conditions on the physicochemical and biochemical parameters of linden, buckwheat, and sunflower honeys during storage for 12 months. For the first time, a wide range of physicochemical parameters of honey samples was analyzed before and during storage for 12 months at temperatures of 18, 10, 5, 0, -5, -10 and -18 (±2) °C. The evaluation of the physicochemical parameters before storage demonstrated that the samples fully complied with the Interstate Standards. Throughout the storage period, the HMF level remained stable at -18 °C, whereas it significantly increased at higher temperatures; for example, after 12 months at 18 °C, the increase ranged from 472.5% to 488.1%, depending on the botanical origin of the honey. However, maximum permissible concentration - MPC (25 mg/kg) was not exceeded. A decrease in the activity of diastase, D-glucose-1-oxidase and catalase was observed at all temperature conditions already during the first month of storage. Minimal changes were observed at 0 and 5 °C. Hydrogen peroxide (H2O2 ) remained stable in this temperature range. Moisture content, total mass fraction of reducing sugars, and acidity did not change significantly in all samples. An antimicrobial study using test cultures found that honey stored at 5 and 0 °C had the greatest inhibitory effect. The data obtained demonstrates that the optimal temperature range for 12-month storage of honey is between 5 and 0 °C. These findings can be used as supplementary guidance when making amendments to regulatory documents governing storage requirements for this product. [ABSTRACT FROM AUTHOR]

Heterotis rountidifolia (Sm.) Jacq. Fel, is employed in Nigeria traditional medicine for the treatment of various diseases. The study investigated the antioxidant, mineral composition and antimicrobial activities of aerial part of Heterotis rotundifolia using standard procedures. The proximate composition on dry matter basis showed high carbohydrate (48.41%) and low lipid (0.77%) contents while mineral content revealed that sodium (5.68 mg/100 g) and zinc (4.64 mg/100 g) were the highest. The total caloric value per 100 g was 260.93 kcal. Methanol (ME) fraction exhibited the highest radical scavenging (EC50 = 59.36 µg/mL) and reducing (EC50 = 76.54 µg/mL) activity. Contents of total flavonoids and phenolics were highest in ME and ethyl acetate (EAE) fractions (39.2 mg GAE/g and 183.5 mg RE/g, respectively), while hexane (HE) fraction showed the lowest radical scavenging, ferric reducing and nitric oxide assay (EC50 = 268.56, 87.86, and 98.30 µg/mL, respectively). The minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) against various bacterial and fungal strains using tube dilution method showed strong activity at MIC of 50 mg/mL depicted by n-HE fraction, though lower MBC of 37.5 mg/mL by ME fraction made the ME fraction of better potentials. Gas chromatography-mass spectrum (GC-MS) analysis of the ME fraction revealed 5-Hydroxymethylfurfural (16.87%), Methyl 6-O-[1-methylpropyl]-β-D-galactopyranoside (16.07%), 4H-Pyran-4-one,2,3-dihydro-3,5-dihydroxy- (8.28%), 6-methyl-β-D-glucopyranose, 1,6-anhydro- (6.56%), 2-heptanol (6.82%), stigmastan-3,5-diene (4.32%) amongst others. This research demonstrates that extract and fractions from aerial part of H. rotundifolia possesses antioxidant, antimicrobial and nutritive potentials, albeit with generally weak antifungal activity and, may be attributed to the presence of its phytochemical constituents. [ABSTRACT FROM AUTHOR]

The main objective of this work was to determine the significant physicochemical and bioactive parameters of honeys originating from Iraqi Kurdistan. For this purpose, honey samples (n = 16) were taken directly from Kurdish beekeepers from different places of Dohuk and Erbil Governorate in 2018 and 2022. The following parameters were analyzed: moisture content, electrical conductivity, diastase activity, hydroxymethylfurfural content, pH, free acidity, content of saccharides, total phenolic content, total flavonoid content, color, color intensity and DPPH, FRAP. Another objective of this work was to compare the properties of Kurdistan honeys with the requirements of European Union law and with the honeys of Central Europe. A total of 48 honey samples were included in the comparison. It was detected that the honeys produced in Iraqi Kurdistan met the strict quality criteria set by European law, which is important information for local beekeepers and experts in relation to honey production and an opportunity to set local limits of honey quality. Despite the different climatic and topographical conditions, the available flora, and the different species of bees, the properties of Iraqi Kurdistan honeys were similar to the properties of honeys from the Czech and Slovak Republics. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The compound 5-(hydroxymethyl)furfural (HMF) has emerged as a versatile intermediate with the ability to undergo conversion into both fuel and a variety of platform chemicals. Lignocellulosic biomass, such as hazelnut shells and tea processing residues, was employed in this study for HMF production through two distinct methods. In the first method, cellulose from biomass was converted to sugars using a 4% acid solution, followed by catalytic conversion with NaCl/CrCl3.6H2O. After a 1-h reaction at 131 °C in a high-pressure system, HMF was obtained from tea processing waste and hazelnut shells with yields of 8.6% (82.3 mg/g) and 6.7% (66.7 mg/g), respectively. The second method involved LiCl/NaCldoped N,N-dimethylacetamide (DMA) as an ionic solvent system for HMF production. After a 2-h reaction at 131 °C in the DMA-NaCl/[EMIM]Cl ionic solvent system, HMF was obtained from tea processing waste and hazelnut shell celluloses with yields of 5.7% (57.5 mg/g) and 3.1% (31.3 mg/g), respectively. This study contributes to the economic conversion of various food wastes into valuable chemicals, highlighting the potential of lignocellulosic biomass in sustainable chemical production. [ABSTRACT FROM AUTHOR]

It has been shown that the nature of the metal precursor and the thermal effects during calcination determine the physicochemical properties of the catalysts and their catalytic activity in the levulinic acid (LA) and 5-hydroxymethylfurfural (HMF) hydrogenation reactions. The endothermic effect during calcination of the inorganic nickel precursor promoted higher metal dispersion and stronger interaction with the alumina surface. In contrast, the exothermic effects during the calcination of organic nickel precursors resulted in smaller metal dispersion and lower interaction with the support surface. A clear relationship was found between the size of the metal crystallites and the yield of LA hydrogenation reaction. The smaller crystallites were more active in the LA hydrogenation reaction. In turn, the size of the metal particles and their nature of interaction with the surface of the alumina influence the hydrogenation pathways of the HMF. [ABSTRACT FROM AUTHOR]

The current work demonstrates the fabrication of cerium-aluminum oxide (CAO) catalysts for the dehydration of fructose to the platform chemical 5-hydroxymethylfurfural (5-HMF). CAO materials with varying chemical compositions and textural properties were obtained through calcination at different temperatures. The fructose conversion and yield of 5-HMF of the catalysts were determined in a dimethyl sulfoxide system. The CAO catalysts were thoroughly characterized, and their catalytic performances evaluated to uncover the origins of their fructose conversion efficiency and product selectivity. The CAO catalyst obtained by calcination at 500 °C (CAO-500) registered remarkably high fructose conversions (~ 95%) and 5-HMF yields (~ 91%) with no side product generation which means that under the optimal process conditions (120 °C, 120 min) determined in the study, the catalyst produces 5-HMF almost exclusively. The exceptional catalytic performance of CAO-500 was intimately linked to the physical and chemical synergies emerging from the co-existence of crystalline (CeO2) and amorphous (Al(OH)3) components in its matrix resulting from the calcination process. This unique composition makes CAO-500 structurally robust and with the necessary abundance of Lewis and Bronsted acid sites that facilitate highly selective fructose conversion to 5-HMF. [ABSTRACT FROM AUTHOR]

Honey, with its varied and extensive characteristics, is a complex and diverse biological substance that has been used since ancient times. The aim of this study is to thoroughly characterize the physicochemical, phytochemical, and biological properties of four floral honey varieties from the Fez-Meknes region in Morocco, with the goal of promoting the valorization of Moroccan honey in skincare and cosmetic products. The analyses of their physicochemical characteristics encompass various parameters such as pH, acidity, density, water content, Brix index, conductivity, ash content, hydroxymethylfurfural (HMF) content, and color. The levels of polyphenols range from 22.1 ± 0.4 to 69.3 ± 0.17 mg GAE/100 g of honey, measured using the Folin–Ciocalteu method for polyphenol quantification. Additionally, the estimation of flavonoid quantities in 100 g of honey, conducted using the aluminum trichloride method, reveals values ranging from 3.6 ± 0.2 to 7.2 ± 0.6 mg QE. Furthermore, it is noteworthy that honey exhibits high levels of glucose and relatively low concentrations of proteins. The quantitative evaluation of antioxidant effects, carried out through the 2,2-diphenyl-1-picrylhydrazyl free-radical-scavenging method and the ferric-reducing antioxidant power (FRAP) method, highlights the strong antioxidant capacity of multifloral honey, characterized by low inhibitory concentration values (IC50 = 30.43 mg/mL and EC50 = 16.06 mg/mL). Moreover, all honey varieties demonstrate antibacterial and antifungal properties, with multifloral honey standing out for its particularly pronounced antimicrobial activity. The correlation analyses between phytochemical composition and antioxidant and antibacterial activities reveal an inverse relationship between polyphenols and IC50 (DPPH) and EC50 (FRAP) concentrations of honey. The correlation coefficients are established at R2 = −0.97 and R2 = −0.99, respectively. Additionally, a significant negative correlation is observed between polyphenols, flavonoids, and antifungal power (R2 = −0.95 and R2 = −0.96). In parallel, a marked positive correlation is highlighted between antifungal efficacy, DPPH antioxidant activity (R2 = 0.95), and FRAP (R2 = 0.92). These results underscore the crucial importance of phytochemical components in the beneficial properties of honey, meeting international quality standards. Consequently, honey could serve as a natural alternative to synthetic additives. [ABSTRACT FROM AUTHOR]

We aimed to evaluate the effect of freeze-drying and vacuum-drying on moisture, water activities (aw), total soluble solid (TSS), hydroxymethylfurfural (HMF), diastase activity, total phenolic content (TPCs), and antioxidant activities (ABTS, DPPH, FRAP, ORAC) of longan (Dimocarpus longan Lour.) blossom honey and Siam weed (Chromolaena odorata Lour.) honey. The fresh longan blossom honey and Siam weed honey were collected from a local apiarist in Northern Thailand. Freeze-drying at 0.013 kPa, −54℃ for 72 h or vacuum-drying at 2.5 kPa at 60 ℃ for 12 h was applied to dehydrate fresh honey. The moisture of freeze-dried samples was 10.10% for longan blossom honey and 11.50% for Siam weed honey, and the aw of both freeze-dried honeys was 0.43. Freeze- and vacuum-dried produced more TSS than fresh honey did (p ≤ 0.05). However, the amounts of TSS derived freeze-dry and vacuum-dry were not significantly different. Freeze-dried honey contained the highest HMF and the lowest diastase activity regardless of honey origins (p ≤ 0.05). Drying processes significantly increased the TPCs levels of honey (approximately 2 folds by freeze-drying method). The antioxidant activity of dried honey was significantly higher than that of fresh honey. It was observed that the freeze-drying method tended to better preserve the antioxidant activity of honey compared to vacuum-drying methods in both types of honey. The results indicated that drying processes significantly affect the quality of dried honey, including TSS, HMF, diastase activity, TPCs, and antioxidant activity. In this study, freeze-drying emerged as the relatively low temperature drying method that can preserve the quality of honey, especially in terms of TPCs and antioxidant activity.

Wild rose hip fruit, pulp, beverage, nectar, as well as technological methods and tools are taken as the object of research. Rose hips have a, bright red color and a rich chemical composition, which makes it a very important raw material for industry. However, insufficient research slows down this work and makes the use of raw materials inefficient. With this in mind, the aim was to study the mechanical and technological characteristics of the femur, which are considered important for industrial processing. The reflection of ripening conditions on the mechanical, physical and chemical properties of rose hips, as well as the influence of processing methods, especially hot processing, on the quality of the product has been established. Research has shown that the percentage of fruit cultivation in the Dashkasan region was the lowest, and the highest in the Gadabay region, and the Goygol region took an intermediate position. The Latin hardness of fruits grown in Dashkasan region was 6.41 N. Gadabay region with 5.56 N and Goygol region with 5.47 N. This indicator plays an important role in the storage and processing of fruits. As a result of the treatment, the amount of dry matter in fruit, pulp and beverage increased slightly, titratable acids, ascorbic acid and pH decreased. An increase in total phenolic compounds was observed during the initial heat treatment of the raw material and was noted to be much lower in the pulp and beverage. Hot treatment had a reducing effect on the amount of ascorbic acid, which is considered one of the main components of indicators in the thigh. The obtained results can be used in individual family farms and in the food industry. [ABSTRACT FROM AUTHOR]

The formation of humins hampers the large-scale production of 5-hydroxymethylfurfural (HMF) in biorefinery. Here, a detailed reaction network of humin formation at the initial stage of fructose-to-HMF dehydration in water is delineated by combined experimental, spectroscopic, and theoretical studies. Three bimolecular reaction pathways to build up soluble humins are demonstrated. That is, the intermolecular etherification of β-furanose at room temperature initiates the C12 path, whereas the C–C cleavage of α-furanose at 130–150 °C leads to C11 path, and that of open-chain fructose at 180 °C to C11′ path. The successive intramolecular dehydrations and condensations of the as-formed bimolecular intermediates lead to three types of soluble humins. We show that the C12 path could be restrained by using HCl or AlCl3 catalyst, and both the C12 and C11′ paths could be effectively inhibited by adding THF as a co-solvent or accelerating heating rate via microwave heating. [ABSTRACT FROM AUTHOR]

Direct conversion of inexpensive biomass into value-added chemicals via furanic platform molecules is highly attractive. In this work, we present a straightforward chemobiocatalytic route for glucose valorization into 2,5-bis(hydroxymethyl)furan (BHMF) in one pot, with no purification of the intermediate 5-hydroxymethylfurfural (HMF). Six candidate alcohol dehydrogenase (ADH) genes were located from Meyerozyma guilliermondii SC1103, based on comparative transcriptome analysis and real-time quantitative polymerase chain reaction. An ADH (MgADH1) was identified upon evaluation of catalytic performances of recombinant Saccharomyces cerevisiae harboring candidate ADHs in HMF reduction. Soluble expression of the enzyme in S. cerevisiae was greatly enhanced by its codon optimization, leading to improved HMF tolerance (up to 400 mM). In a fed-batch process, the desired product of approximately 473 mM (60.5 g/L) was produced within 30 h by recombinant S. cerevisiae_MgADH1. A chemobiocatalytic route toward BHMF was constructed by merging CaCl2-mediated isomerization and dehydration with biocatalytic reduction with an overall yield of approximately 42%, starting from glucose. This work may pave the way for green manufacture of valuable biobased chemicals. [ABSTRACT FROM AUTHOR]

The demand for honey produced by stingless bees such as Melipona beecheii has increased due to its therapeutic properties. However, its physico-chemical characterization is still limited and quality control parameters are not sufficiently established. The objective of this study was to evaluate physico-chemical characteristics of M. beecheii honey obtained in various production seasons in meliponaries from the low deciduous forest zone of Yucatan, Mexico. Thirty-seven samples of honey were obtained in the harvest and post-harvest seasons during 2020-2021. According to the International Honey Commission methodologies, physico-chemical analyses were carried out and statistical analysis was performed to determine differences between seasons in the parameters evaluated. There were significant differences (p < 0.05) between harvesting seasons in the CIE colour parameters L*a*b* (3.03, 0.47, 0.43 and 3.48, 1.85, 3.05, respectively), free acidity (21.3 meq·kg-1 and 32.4 meq·kg-1), ash (2.3 g·kg-1 and 4.5 g·kg-1), hydroxymethylfurfural content (11.8 mg·kg-1 and 20.4 mg·kg-1, and invertase number (7.8 and 11.6). For moisture, sugars, electrical conductivity, diastase activity, insoluble matter and proline content, no differences were found (p > 0.05) between honeys extracted at harvest and post-harvest seasons. The differences could be related to the diversity of melliferous flora present in this ecoregion. [ABSTRACT FROM AUTHOR]

Honey quality is conventionally controlled by checking its compliance with the regulatory standards mainly through physical properties. A new index of honey quality known as the Honey Health Impact Metric (HHIM) which considers two main parameters related to health was developed for use as a more market-relatable criteria in the honey industry. The HHIM incorporates the balancing of the positive health-beneficial 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity with the negative health-detrimental hydroxymethylfurfural (HMF) concentration present in honey. It is defined as the average score between fractional DPPH and the normalised HMF. The HHIM was tested using 30 randomly selected honey samples from different origins which were then graded by the different categories of quality. As both parameters are also affected by honey storage period, the HHIM was also used to monitor changes in two specific honey samples, the Kelulut Itama and Tualang Dorsata. With quality of honey deteriorating over storage time following a zero-order kinetic model, the indications by HHIM gave a storage recommendations of 10 to 12 months for both these honey samples. This idea of HHIM as an alternative honey quality indicator to gauge health potential of honey will support the genuine and real products in the honey industry. [ABSTRACT FROM AUTHOR]

Background: Honey, a naturally sweet food product, exhibits several health beneficial effects. The quality of honey differs by its microbiological, physicochemical, and antioxidant properties, which can significantly vary from brand to brand and country to country. Objectives: This study aimed to assess the physicochemical properties and antioxidant activity of honey brands distributed in Tehran City, Iran, and compare these parameters with national and international standards. Methods: Five brands (Shakelli, Khansar, Golagin, Shafi, and Kral) of honey in Tehran were selected, and 5 samples of each brand were collected from supermarkets and analyzed by standard methods for physicochemical properties and antioxidant activity. The collected data were analyzed using SPSS software, version 20. Results: The results depicted significant differences among studied honey brands in all physicochemical properties (except for ash, total reducing sugars, and sucrose content) and antioxidant activity (P<0.05). The moisture, ash, pH, free acidity, total reducing sugars, sucrose, diastase, and 5-hydroxymethylfurfural (HMF) contents of honey brands ranged within 16.30%-15.34%, 0.24%-0.40%, 4.27-4.39 units, 9.15-10.68 meq/kg, 77.84%-79.74%, 3.66%-4.57%, 2.28-3.28 DN (diastase number), and 6.67-11.84 mg/kg, respectively. Thus, the physicochemical properties of studied honey brands, except for diastase activity, were within national and international legal ranges. Moreover, total phenolic contents (TPC) and radical scavenging activity (RSA) of 1,1-diphenyl-2-picrylhydrazyl (DPPH) of honey brands ranged within 28.72-39.36 mg GAE/100 g and 63.83%-73.91%, respectively. In addition, a highly significant positive correlation was observed between TPC and RSA of DPPH of honey samples (r=0.798, P<0.01). Conclusion: The studied honey brands were of good quality and met national and international standards. [ABSTRACT FROM AUTHOR]

The present work aimed to characterise oven-dried honey-sugar powders at vacuum temperatures (30 and 40°C) with dextrose, maltodextrin, and sucrose as the sugar carrier (incorporated at 50, 60, and 70%) for application in chocolate. Honey has high water content, and therefore, its direct use in chocolate will negatively affect the rheological properties of chocolate. Dextrose can produce a honey powder with the least heat degradation, hence maintaining the good health functionality of honey. Maltodextrin is the most common carrier used in honey-powder processing, while sucrose is the most common ingredient used in chocolate. The physical appearance and other physicochemical properties such as moisture content, hygroscopicity, glass transition temperature, hydroxymethylfurfural (HMF) content, and diastase activity were assessed for characterisation. Results showed that the honey-sugar powder that was dried at 40°C with 70% sugar carrier exhibited better properties in terms of physical appearance, moisture content, and hygroscopicity, with the HMF content and diastase activity not significantly affected by both factors. Therefore, honey-sugar powders dried at 40°C with 70% sugar carrier incorporation could have further application in chocolate. The impact of honeysugar powder on chocolate rheological properties and their functionality in promoting health benefits is crucial for their potential application in the future. [ABSTRACT FROM AUTHOR]

The economically viable and sustainable production of xylo-oligosaccharides (XOS) still challenges researchers. The enzymatic hydrolysis of the hemicellulosic fraction is one of the most investigated methods, since it is a more efficient process, easier to control, and less harmful to the environment, which are the main variables to be investigated. This study evaluated the application of the bamboo culm of Dendrocalamus latiflorus in optimizing xylo-oligosaccharides production by the enzymatic hydrolysis of arabinoxylan extracted from this plant matrix using a low-cost commercial enzyme cocktail. Applying a 2% substrate load, 50 °C temperature, pH 5.0, enzymatic load of 7.5 mg of protein/g of xylan, for only 24 h of hydrolysis were the ideal conditions to obtain a high concentration of short-chain xylo-oligosaccharides, especially xylobiose and xylotriose (oligomers with greater prebiotic effect). The low amount of xylose and the lack of inhibitory compounds such as furfural and hydroxymethylfurfural also indicate the high purity of the XOS obtained (~ 97%) without the need for purification processes that could raise costs and make the process economically unfeasible. [ABSTRACT FROM AUTHOR]

In pursuit of designing a bio-based catalyst for the dehydration of biomass (i.e., fructose) to 5-hydroxymethylfurfural, a novel catalytic composite was prepared by in-situ formation of an Al-based metal–organic framework in the presence of chitosan. To enhance the acidity of the as-prepared catalyst, it was sulfonated with chlorosulfonic acid. Various characterization techniques, including XRD, XPS, FTIR, SEM/EDX, TGA, and elemental mapping analysis were applied to validate the formation of the acidic composite. Fructose dehydration conditions were also optimized using Response Surface Method (RSM) and it was found that reaction in the presence of catalyst (23 wt%) in DMSO, at 110 °C for 40 min led to the formation of HMF in 97.1%. Noteworthy, the catalyst was recyclable and stable up to five runs with a minor reduction in its activity. [ABSTRACT FROM AUTHOR]

In this study, two different evaporation rates (30% and 50%) were applied to milk and banana, strawberry and cocoa milk jams were produced by adding 1.5% flavouring. This paper aims to mitigate intense heat typically used in traditional milk jam production, thereby reducing its adverse effects on the product. In addition to composition properties (dry matter, ash, fat and protein), acidity (titratable acidity and pH), HMF, total mesophilic aerobic bacteria, colour, texture, and sensory characteristics were determined at the 1st, 11th, and 21st storage days. The data indicated no change in the compositional properties of samples, while HMF values were lower in samples with higher evaporation rates (up to 50% dry matter) depending on the level of evaporation applied. Shorter boiling time of the same samples caused higher L* and hardness values. All the milk jam samples produced with varying evaporation levels and flavourings were found to have acceptable properti es. [ABSTRACT FROM AUTHOR]

Summary: Post‐harvest maturation of two Malaysian honeys, the Tualang and Kelulut was studied by measuring changes in physicochemical and antioxidant properties, hydroxymethylfurfural (HMF) contents and bacterial profiles at room temperature of 23–26 °C. After maturation at the recommended period of 26 weeks, water activity of both honeys increased between 0.89% and 2.34% while free acidity increased between 2.05% and 2.24%. Results suggested the prominence of fermentation reactions in honey during post‐harvest maturation as fructose concentration reduced by 10.6% and 1.05% for the Tualang and Kelulut honey, respectively, while HMF concentrations were kept at a safe limit of 48.00 and 61.23 mg/kg honey. The total phenolic content of Tualang and Kelulut honey increased significantly by 12.61% and 54.66% respectively. The highlight of this post‐harvest maturation process for Kelulut honey was the improvement found in antioxidant properties of DPPH radical scavenging activity by 10.01%–54.74% and also the probiotic‐like potential in terms significant increase in relative abundance of the Bacillus genera to 2.6% and Lactobacillus to 6.25% at 26 weeks. The prolonged maturation process up to 1 year however revealed continuous accumulation of HMF to values above 80 mg/kg honey, surpassing the limits by the Codex Alimentarius Commission despite improvements of antioxidant properties and bacterial profiles. [ABSTRACT FROM AUTHOR]

Garlic (Allium sativum L.), a member of the Alliaceae family, has been widely used in cuisine and traditional medicine since ancient times. Black garlic is produced by fermentation of fresh garlic under controlled conditions for a certain period at high temperature (60-90°C) and high humidity (70-90%). According to the Turkish Statistical Institute (TURKSTAT) data, Kastamonu and Gaziantep garlic varieties are the most cultivated garlic varieties in our country. Changes in protein, sugar content, antioxidant capacity (DPPH and ABTS methods), total phenolic content, 5-hydroxymethylfurfural (HMF) content, and organosulfur compound profiles were investigated in samples taken from Kastamonu and Gaziantep fresh garlic at 7, 14, 21, and 28 days of black garlic production under 65°C temperature and 70% humidity conditions. With these analyses, the differences between black garlic and fresh garlic and the changes in black garlic during the production process were revealed in detail. It was determined that the amount of total phenolic content and antioxidant capacities increased in the black garlic production processes of both regions compared to fresh garlic. While sucrose was fresh garlic's dominant sugar, fructose was black garlic's dominant sugar. Among the organosulfur compounds, allicin was dominant in fresh garlic and SAC in black garlic. It was determined that SAC was formed after the enzymatic conversion of ɣ-glutamyl-S-alk(en)yl-L-cysteine and ɣ-glutamyl and the temperature and fermentation time used in black garlic production increased the formation of SAC. The protein content ranging between 5.8%-7.3% in fresh garlic was 13.1-14.2% in black garlic. Fresh and black garlic from the Gaziantep region was determined to have higher total phenolic content, antioxidant capacity, and organosulfur compound contents. [ABSTRACT FROM AUTHOR]

This work aimed to evaluate the catalytic activity of the catalysts niobium phosphate (PNb), niobium acid (HNb) and the 1:1 mechanical mixture of both catalysts (HPNb) based on the results obtained for the yield of glucose, xylose, 5-hydroxymethylfurfural (HMF) and furfural (FF) using holocellulose, solid material with a high cellulose and hemicellulose content, as raw material. The variables studied were temperature and time between 150 and 200 °C and 0 and 360 min. The reaction mixture consisted of an aqueous solution containing 6% (m/m) holocellulose and a holocellulose/catalyst ratio of 3:1. The highest yield obtained for HMF was 44.8 g/kg(holocellulose) at 200 °C with a reaction time of 60 min. For FF, a 69.8 g/kg(holocellulose) yield was obtained at 200 °C and 90 min. The yields obtained with HPNb exhibited intermediate results compared to PNb and HMF catalysts, with no significant differences justifying using a mixture of both catalysts. [ABSTRACT FROM AUTHOR]

This research studies the influence of the addition of defatted press cakes (from the production of hazelnut, camelina, pumpkin, and hemp seed oil) on nutritionally important components: fibre, resistant starch, polyphenols, hydroxymethylfurfural (HMF), and acrylamide in directly and indirectly expanded snacks. The amounts of press cakes added to corn grits were 3, 6, and 9%. Extrusion was carried out in a laboratory single-screw extruder. For indirectly expanded products (SCFX), supercritical CO2 was injected during extrusion, and secondary expansion was completed in the microwave oven. The type and content of press cake, as well as the type of product, significantly influenced total polyphenol content and antioxidant activity. Press cakes increased the contents of both soluble and insoluble fibre (from 1.94% d. m. and 1.28% d. m. for extrudates without press cakes up to 3.17% d. m. and 6.94% d. m. for SCFX extrudates with press cakes, respectively), and resistant starch was not markedly influenced by their addition. The influence of the content of press cake on HMF was not significant, whereas the type of cake and the type of extrusion influenced HMF significantly. In a raw mixture of corn grits with 3% of pumpkin press cake, HMF was below the limit of detection, and the highest content was found in the classically extruded sample with the addition of 9% of camelina press cake (580 ppb). In all samples, the acrylamide content was below the limit of detection, indicating that safe products were obtained. This research shows potential for the implementation of supercritical CO2 extrusion in the production of safe, nutritionally improved snack products. Future research might bring about the design of cost-effective processes applicable in the industry. [ABSTRACT FROM AUTHOR]

5-Hydroxymethylfurfural (5-HMF) is the key to unlocking the potential of biomass materials to transform into fuels, materials, and chemicals. In this study, an effective biphasic reaction system composed of a reaction phase (aqueous phase) and an extraction phase (organic phase) was used for the conversion of fructose to 5-HMF. Deep eutectic solvents (DESs) composed of different hydrogen bond donors and hydrogen bond acceptors, the ionic liquid [BMIM]Cl, aqueous choline chloride, aqueous betaine hydrochloride, and ethylamine hydrochloride were used as the reaction phase, and different organic solvents, such as methyl isobutyl ketone (MIBK), dimethyl sulfoxide (DMSO), toluene, ethyl butyrate, and gamma-valerolactone (GVL), were used as the organic phase. Experiments were conducted under optimal conditions simulated using the reaction surface method to obtain the maximum 5-HMF yield. The highest yields of 5-HMF obtained in reactions with DESs were 67.86%, 68.69%, and 71.40% for ChCl : OA, ChCl : Lac, and EaCl : Lac, respectively. However, adding dimethyl sulfoxide and betaine hydrochloride aqueous solution to the fructose conversion system resulted in a maximum yield of 90.42% ± 1.46% of 5-HMF without the use of catalysts. This study also demonstrated that betaine hydrochloride could be effectively reused four times. A 5-HMF yield of at least 80% indicates a green process suited towards sustainable development. [ABSTRACT FROM AUTHOR]

Biomass is an attractive raw material for the production of fuel oil and chemical intermediates due to its abundant reserves, low price, easy biodegradability, and renewable use. Hydroxymethylfurfural (5‐HMF) is a valuable platform chemically derived from biomass that has gained significant research interest owing to its economic and environmental benefits. In this review, recent advances in biomass catalytic conversion systems for 5‐HMF production were examined with a focus on the catalysts selection and feedstocks' impact on the 5‐HMF selectivity and yield. Specifically, the potential of zeolite‐based catalysts for efficient biomass catalysis was evaluated given their unique pore structure and tunable (Lewis and Brønsted) acidity. The benefits of hierarchical modifications and the interactions between porosity and acidity in zeolites, which are critical factors for the development of green catalytic systems to convert biomass to 5‐HMF efficiently, were summarized and assessed. This Review suggests that zeolite‐based catalysts hold significant promise in facilitating the sustainable utilization of biomass resources. [ABSTRACT FROM AUTHOR]

The study aimed to optimise the process of basundi manufacture by ohmic heating (OH) instead of thermal processing. The factors considered were the type of milk (cow milk, buffalo milk and mixed milk), sucrose concentration (5, 7.5, and 10% [w/w] of milk) and voltage gradient (12.5, 13.33, 14.29, 15.38 and 16.66 V/cm). The parameters considered were physico‐chemical, rheological and sensory quality. The optimised product was prepared with standardised buffalo milk (BM), 5% (w/w of milk) added sucrose and processed at 13.33 V/cm. It significantly (P < 0.05) affected the physico‐chemical properties of the optimised product and basundi showed pseudoplastic behaviour. [ABSTRACT FROM AUTHOR]

An efficient solvent mediated & use of metal-free catalyst strategy was developed for synthesis of FDCA over two steps. A simple & economical glucose-hydrothermally carbonized (Glu-HTC) catalyst was prepared and evaluated for synthesis of 2,5-Diformyl furan (DFF) from fructose & 5-hydroxymethylfurfural (HMF) in the 1st step. DFF was then converted to FDCA using Pinnick oxidation in the 2nd step. DFF was obtained in 82% & 86% yields from fructose & HMF respectively whereas FDCA was obtained in 94–95% yield from DFF. FDCA was thus formed in an overall yield of 78% and 81% from fructose & HMF respectively. This strategy eliminated use of expensive noble metals for FDCA synthesis and also intermediates such as HMFCA & FFCA were not observed after the reaction as DFF was completely oxidized to FDCA. [ABSTRACT FROM AUTHOR]

Honey is a natural nice substance produced by bees, physicochemical properties of bee’s honey to help beekeepers procreation high-quality bee’s honey. A total number of 20 Libyan honey samples were collected from different areas in Libya through 2016 – 2017, from east, west, southeast and southwest regions. These samples were analyzed for six physiochemical parameters of honey control i.e.,pH, moisture, ash content, insoluble mater porline control and HMF . The aim of this study is to give view about the quality of Libyan honey, which is suffering from paucity of characterization data. The results of physiochemical characteristic of Libyan honey samples, the pH of Libyan honey samples range from 3.25 to 5.00, with a mean of 4.101 . These values are comparable to the pH values of U.S. honey (range 3.4 to 6.1), the moisture content of honey samples range from 7.76 to 15 % which is found within the limits prescribed by Codex Alimentarious Commission(1969), i.e. not more than 21%. The mean of ash content of honey samples were 0.313 %, with the range of 0.1-0.95 %. These values are comparable to the values of U.S. honey which has mean of o.169%, with a range from 0.020 to 1.028%. The Hydroxymethylfurfural (HMF) content of Libyan honey samples are found within the limits prescribed by the Codex Alimentarious Commission(1969), Insoluble matter content of Libyan honey samples range from 0.005 to 0.149 % . with mean of 0.06175 % . The range of proline content of Libyan honey samples arek from 350 to 1079.4 mg / kg, with mean of 626.2 mg / kg. [ABSTRACT FROM AUTHOR]

The effect of heavy metals on the formation of hydroxymethyl furfural (HMF) from degradation of reducing sugars in honey collected from Ilu Woreda, West Shewa Zone of Oromia Regional State, Ethiopia were studied. The concentration level of Pb, Cd, Cr and Ni in honey sample was determined using AOAC Official Method. The concentration of HMF in honey was determined using international honey commission standards. The concentrations of heavy metals in fresh honey were 11 ± 0.001, 454 ± 0.002, 630 ± 0.001 and 1 ± 0.001 µg kg-1 for Pb, Cr, Ni and Cd, respectively. The influence of heavy metals on the formation of HMF in honey samples was studied on 5, 30 and 60 days after spiking at concentration level of 10,000 µg kg-1 of each heavy metal. The concentration of HMF for untreated honey samples was ranged 1380-2200 µg kg-1 for the storage time of 5, 30 and 60 days. The concentration of HMF in honey samples spiked with Pb, Ni, Cr and Cd were found to be in the range of 2100-2150, 1900-2430, 2100-2270 and 2050-2330 µg kg-1, respectively. The results of this study indicate that contamination of honey with heavy metal facilitate the formation of HMF. [ABSTRACT FROM AUTHOR]

5-Hydroxymethylfurfural (HMF) is a high value-added platform compound, converted into bio-based polyesters and biofuels etc. In this paper, we used two commercially available hexamethylenimine and cetyltrimethylammonium bromide (CTAB) as the structure-directing agents to synthesize HMWW zeolite nanosheets via one step. A series of HMWW zeolite nanosheets with different disorder index (DI) were controllably prepared by adjusting the amount of CTAB, operating also as an in situ exfoliating agent, converting fructose into HMF in the tetrahydrofuran/NaCl-H2O biphasic solvent with low boiling point. Successful construction of disordered HMWW zeolite nanosheets was verified by PXRD. Further characterizations by BET, SEM and TEM etc. show that HMWW4.0 with the optimum DI of 0.67 has a disordered network-like arrangement of layers with the external surface area of 224 m2/g and the mesoporous size of 3.5 nm. Catalytic evaluations showed that HMF selectivity was closely related to DI of the catalysts. Under the optimized DI, fructose molecules are readily accessible to acidic sites on the external surface while larger external surface area is exposed. The HMWW4.0 zeolite catalyzed fructose dehydration in the biphasic solvent, producing 90% HMF selectivity with 93% fructose conversion at 140 °C for 6 h. In the reuses of the HMWW4.0 catalyst, HMF selectivity was around 90% with fructose conversion decreasing by ca. 10% after six runs, indicating that it possesses the promising stability. [ABSTRACT FROM AUTHOR]

Acrylamide (AA) and 5-hydroxymethylfurfural (HMF) are by-products of the Maillard reaction that occur during the frying process. These substances are toxic and pose a potential health risk because they are consumed in high amounts in Western diets. We investigate using plant extracts, including cinnamon, clove, curry leaf, mint, and turmeric, to reduce these harmful compounds while preparing French fries. Our results demonstrate the significant potential of curry leaf and mint leaf extracts, which have not been previously explored in this context, in effectively inhibiting AA and HMF formation. We observe that eugenol and cinnamic acid in cinnamon and clove extracts suppress HMF and AA formation, although to a lesser extent than other extracts. Notably, we establish an inverse relationship between the reducing properties of the extracts and the formation of toxicants. Furthermore, our research emphasize the crucial role of blanching, which, when combined with soaking, proves more effective in reducing AA and HMF content than soaking alone. Overall, this research highlights the promising application of natural plant extracts and the significance of blanching in enhancing food safety and quality while preparing fried potatoes.