Search Results (24)

(1) Research Highlights: This study provides the first integrated assessment of Scots pine (Pinus sylvestris L.) growing in the urban forests of Karaganda, Kazakhstan, a city consistently ranked among the most air-polluted cities globally. We examined the adaptive phyto-chemical response of needles to extreme technogenic stress and evaluated their dual potential as biological filters and renewable sources of bioactive compounds. (2) Background and Objectives: Urban forests are critical for mitigating air pollution; however, the biochemical responses of trees in heavily industrialized environments remain poorly understood. Karaganda faces severe atmospheric pollution from mining, metallurgy, and energy sectors, with particulate matter (PM) levels exceeding permissible limits by up to 20-fold. This study aimed to evaluate the state of Pinus sylvestris, a key component of local protective plantations, by studying heavy metal accumulation, anatomical localization of secondary metabolites, and the phytochemical profile and biological activity of needle extracts obtained using different extraction techniques. (3) Materials and Methods: Needles were collected from 15 trees across three sites in Karaganda’s industrial green zones. Heavy metal content (Pb, Cd, As, and Hg) was determined using atomic absorption spectroscopy and voltammetry. Anatomical–histochemical analysis localizes major metabolite classes. Liquid extracts were prepared using four methods, percolation (PER), vortex-assisted (VAE), microwave-assisted (MAE), and ultrasound-assisted (UAE) extraction, and analyzed by GC-MS. Antimicrobial activity was tested against S. aureus, B. subtilis, E. coli, and C. albicans using the disk diffusion method. The antioxidant capacity (water- and fat-soluble) was measured amperometrically. Statistical analysis was performed using one-way ANOVA with Tukey’s HSD test (p < 0.05). Results: Despite extreme ambient pollution, heavy metal concentrations remained below pharmacopoeial limits (Pb < 0.1, Cd < 0.05, As < 0.01, Hg < 0.001 mg/kg), indicating effective biofiltration without toxic accumulation. Histochemistry confirmed the active synthesis of protective phenolics, flavonoids, and essential oils in the mesophyll, epidermis, and schizogenic cavities. GC-MS identified 72 compounds in the PER extract, 70 (the VAE), 72 in (MAE), and 46 in (UAE). The PER extract exhibited the highest relative abundance of bioactive terpenoids: α-cadinol (5.24%), α-muurolene (4.32%), and caryo-phyllene (2.20%). UAE extracts exhibited elevated 5-hydroxymethylfurfural (6.90%), indicating degradation. Antimicrobial testing revealed that PER produced the largest inhibition zone against S. aureus (15.0 ± 1.0 mm), significantly exceeding that of the other methods (p < 0.001). PER extract also demonstrated the highest water-soluble antioxidant capacity (3600 ± 0.40 mg quercetin equiv./dm³) and substantial fat-soluble activity (1633 ± 0.23 mg gallic acid equiv./dm³). (4) Conclusions: Pinus sylvestris in Karaganda exhibits remarkable adaptive resilience, maintaining safe heavy metal levels while accumulating a rich repertoire of stress-induced secondary metabolites. Classical percolation optimally preserves this native phytocomplex, yielding extracts with superior antimicrobial and antioxidant properties. These findings support a dual-use model wherein urban pine plantations simultaneously serve as living biofilters and renewable sources of standardized bioactive extracts, a concept with direct implications for circular bioeconomy strategies in industrial regions worldwide. This supports the strategic importance of coniferous plantations for bioremediation and sustainable resource use in industrial regions. Full article

This study investigates the effects of electric field pretreatment parameters such as electric field strength (0.1–0.2 kV/cm), waveform (sinusoidal vs. square), and application mode (continuous vs. pulsed) on the quality attributes of dried Fuji apple slices, including ascorbic acid (vitamin C) retention, β-carotene content, and hydroxymethylfurfural (HMF) formation. Electric-field-treated samples were compared to untreated controls after convective drying at 75 °C. Results revealed that vitamin C was significantly influenced by waveform, with sinusoidal waves preserving about 27% more vitamin C than square waves, likely due to reduced oxidative degradation from gentler electroporation. Conversely, square waves caused the highest β-carotene losses (25% vs. control), attributed to prolonged peak voltage destabilizing carotenoids. HMF formation was reduced by 10–23% in electric-field-treated samples compared to controls, linked to accelerated drying rates limiting Maillard reaction time. Low electric field strengths (0.1–0.15 kV/cm) enhanced antioxidant activity; however, higher intensities showed a potential decline. The square waveform had a more detrimental effect on phenolic compounds than the sinusoidal waveform. These findings suggest that low electric field pretreatment, particularly with sinusoidal waveforms at 0.2 kV/cm, enhances drying efficiency while balancing nutrient retention and HMF mitigation, offering a promising strategy for producing high-quality dried fruits. Full article

This study evaluated the potential of pectin (PEC)-based coatings, enhanced with olive leaf extract (OLE) and chitosan nanoparticles (CH-NPs), to mitigate the formation of harmful compounds during the frying of French fries. The research compared deep fat and hot air frying methods. Initial characterization of the coating solutions included assessing zeta potential, Z-Average, polydispersity index, and antioxidant capacity. The inclusion of OLE and CH-NPs significantly boosted antioxidant activity, reaching 78.9%, without substantially altering zeta potential or Z-Average characteristics. Notably, hot air frying induced significantly higher levels of acrylamide (ACR) and hydroxymethylfurfural (HMF) compared to deep fat frying. However, the application of the developed coatings demonstrated a marked reduction in both ACR and HMF across both frying techniques. Furthermore, the coatings, particularly PEC with OLE and CH-NPs, effectively decreased oil absorption by 55% while simultaneously increasing moisture content. The sensory evaluation indicated that the panelists liked the deep-fat-fried fries significantly more compared to hot air frying. Deep-fat frying led to an elevated browning index, which was significantly counteracted by the application of the coatings. These findings underscore the importance of informing consumers about the potential for increased ACR and HMF formation during hot air frying, despite its advantages in reducing fat content, to ensure informed dietary choices. Full article

The use of alternative flours is becoming more common in the food industry to enhance the nutritional and sensory properties of baked goods. However, these changes may also affect the formation of acrylamide, a potentially carcinogenic and genotoxic compound generated in foods heated above 120 °C. This study evaluated the acrylamide-forming potential of 16 flours from cereals, pseudocereals, legumes, fruits, and roots. Samples were analyzed for acrylamide precursors—reducing sugars and free asparagine—and tested in model dough systems with and without added glucose. All samples were baked at 150 °C for 30 min. Hydroxymethylfurfural (HMF) was also determined as a marker of thermal damage. In water-hydrated systems, acrylamide was only detected in wheat, rye, and coconut flours (23–61 µg/kg). When glucose was added, acrylamide levels increased in all systems except cassava. Lentil flour produced the highest levels (154 µg/kg), while corn flour showed the lowest (20 µg/kg). HMF levels followed a similar trend, with lentil flour again showing the highest content (232.3 mg/kg). These results highlight the importance of evaluating acrylamide formation when using non-wheat flours, especially in formulations containing sugars. Additional mitigation strategies may be needed to ensure the safety of these innovative food products. Full article

This study aimed to evaluate the effect of two-year storage of varietal honeys (buckwheat, linden, rapeseed, honeydew, and multifloral) at various temperatures (4 °C, −18 °C, −40 °C, and −80 °C) on the content of 5-hydroxymethylfurfural (5-HMF), diastase number (DN), and color assessed in the CIE L*a*b* system. The control samples were stored at room temperature (RT, ca. 20 °C). The results indicate that storing honey at low temperatures effectively mitigates undesirable quality changes, particularly enzymatic degradation and color alterations, while preventing excessive 5-HMF accumulation. After storage, a significant (p ˂ 0.01) decrease was noted in the diastase number (DN) of the honeys, regardless of the temperature (by ca. 66.7% at RT and by 53.1% to 58.3% at low temperatures, p > 0.05). Low storage temperatures led to higher enzymatic activity in buckwheat, linden, and honeydew honeys compared to rapeseed honeys. RT significantly (p ˂ 0.01) increased 5-HMF concentration by 79.3%, whereas the cold and frozen storage conditions increased 5-HMF concentration only by 25.1% at −18 °C and 33.2% at 4 °C. The greatest color changes manifested by significant (p ˂ 0.01) darkening, with a decrease in the h° value (p ˂ 0.01), and a lower contribution of the yellow color and a greater contribution of red color (p > 0.05) in the color profile were noted in the honeys stored at RT. Storage at this temperature resulted in a significantly (p ˂ 0.01) higher total color difference of the honeys (ΔE = 9.53) compared to the other temperatures tested (3.71 < ΔE < 5.58). The low storage temperatures may elicit a positive and comparable effect on preserving the satisfactory quality of the analyzed varietal honeys. It is noteworthy that this positive effect could already be achieved at a storage temperature of +4 °C without the need to apply frozen storage temperatures, which is essential given the economic and environmental concerns. Full article

Acrylamide (AA) and 5-hydroxymethylfurfural (HMF), which are potentially carcinogenic to humans, are often produced during the hot processing of foods. This study first used a molecular docking model to simulate the binding behavior of four lactic acid bacteria peptidoglycans (PGNs) to AA/HMF, and the binding rate of LAB-based PGNs to AA/HMF was evaluated in vitro. In silico results show that interaction energy is the driving force responsible for the adsorption of LAB-derived PGNs to AA/HMF. In vitro results showed that the PGN of B. lactis B1-04 bound the most AA (28.7%) and HMF (48.0%), followed by L. acidophilus NCFM, B. breve CICC 6079, and L. plantarum CICC 22135. Moreover, an AA/HMF-bound layer on the cell surface of B. lactis B1-04 was observed via AFM and SEM due to adsorption. XPS analysis indicated the removal rate of AA/HMF by selected strains was positively correlated with the proportion of C-O, C=O, and N-H groups of PGNs. The atoms O1, O2, O3, O4, N1, N2, N3, H1, and H2 are involved in the adsorption of LAB-based PGNs to AA/HMF. Thus, the PGNs derived from these four Lactobacillus strains can be regarded as natural adsorbents for the binding of AA/HMF. Full article

The utilization and development of biomass resources is an efficient solution to mitigate the fossil energy crisis. Based on the advantages of mild reaction conditions, rapid reaction, and high conversion, the synthesis of 2,5-furandicarboxylic acid (FDCA) by the electrocatalytic oxidation of 5-hydroxymethylfurfural (HMFOR) has attracted considerable attention. This review will summarize the recent advances of HMFOR to FDCA, including the reaction pathway and mechanism, as well as the catalytic performance of various heterogeneous electrocatalysts. The challenges and prospects for HMFOR are also focused on. Finally, it is expected that this work may provide guidance for the design of high-efficiency electrocatalysts and thereby accelerate the industrialization process of biomass utilization. Full article

Wheat is a staple crop, consumed worldwide as a major source of starch and protein. Global intake of wheat has increased in recent years, and overall, wheat is considered to be a healthy food, particularly when products are made from whole grains. However, wheat is almost invariably processed before it is consumed, usually via baking and/or toasting, and this can lead to the formation of toxic processing contaminants, including acrylamide, 5-hydroxymethylfurfural (HMF) and polycyclic aromatic hydrocarbons (PAHs). Acrylamide is principally formed from free (soluble, non-protein) asparagine and reducing sugars (glucose, fructose and maltose) within the Maillard reaction and is classified as a Group 2A carcinogen (probably carcinogenic to humans). It also has neurotoxic and developmental effects at high doses. HMF is also generated within the Maillard reaction but can also be formed via the dehydration of fructose or caramelisation. It is frequently found in bread, biscuits, cookies, and cakes. Its molecular structure points to genotoxicity and carcinogenic risks. PAHs are a large class of chemical compounds, many of which are genotoxic, mutagenic, teratogenic and carcinogenic. They are mostly formed during frying, baking and grilling due to incomplete combustion of organic matter. Production of these processing contaminants can be reduced with changes in recipe and processing parameters, along with effective quality control measures. However, in the case of acrylamide and HMF, their formation is also highly dependent on the concentrations of precursors in the grain. Here, we review the synthesis of these contaminants, factors impacting their production and the mitigation measures that can be taken to reduce their formation in wheat products, focusing on the role of genetics and agronomy. We also review the risk management measures adopted by food safety authorities around the world. Full article

The ability of additives to reduce the formation of acrylamide in simulated sugar cane syrups was investigated. Organic acids, B vitamins, and inorganic salts were added individually and in combination to simulated thickened cane juice, and the mixtures were heated at 120 °C for 30 min. Calcium chloride (1%), citric acid (0.1%), and vitamin B3 (0.1%) were the most effective individual additives from each chemical family. The effects of CaCl₂ (0–1%), citric acid (0–0.125%), and vitamin B3 (0–0.1125%), when added in combination, on the concentrations of acrylamide and hydroxymethylfurfural (HMF) were studied using a Box–Behnken design. Combinations of all three additives lowered the acrylamide production, but only the combination of citric acid and vitamin B3 had a significant synergistic effect. However, all these additives stimulated the production of HMF, and no significant interactive effect between pairs of additives on HMF production was observed. Calcium chloride stimulated the formation of HMF most strongly. These results indicate that certain combinations of these additives effectively reduce acrylamide formation, but they also lead to an increase in the formation of HMF in sugar syrup. Full article

Thermally processed food always contains various types of harmful substances. Control of their levels in food is important for human health. This work used the extracts from green tea dust, old green tea, yellow tea, white tea, oolong tea, and black tea to simultaneously mitigate diverse harmful substances in fried potato chips. The six tea extracts (30 g/L) all showed considerable inhibitory effects on the formation of 5-hydroxymethylfurfural (reduced by 19.8%–53.2%), glyoxal (26.9%–36.6%), and methylglyoxal (16.1%–75.1%). Green tea and black tea extracts exhibited better inhibitory abilities than the other three teas and were further investigated for other harmful compounds by various concentration treatments. Finally, pre-soaking of fresh potato slices in 50 g/L extracts of green tea dust displayed, overall, the most promising inhibitory capacity of HMF (decreased by 73.3%), glyoxal (20.3%), methylglyoxal (69.7%), acrylamide (21.8%), and fluorescent AGEs (42.9%) in fried potato chips, while it exhibited the least impact on the color and texture. The high level of catechins in green tea dust may contribute most to its outstanding inhibitory effect, whereas the distinguished inhibitory effect of black tea extract was speculated to be attributable to the high levels of theaflavins and amino acids in the fully fermented tea. This study indicated that green tea dust, a predominant waste of the tea industry, had great potential to be exploited to improve food quality and safety. Full article

Chitosan–genipin (Ch-Ge) films have been proposed for the replacement of sulfur dioxide (SO₂) in white wines preservation to circumvent the adverse health consequences caused by SO₂ intake. To assess the effects of different-sized Ch-Ge films (25 and 100 cm²) on wine composition compared to SO₂-treated and untreated wines, nuclear magnetic resonance metabolomics was applied. Relative to SO₂, 100 cm² films induced significant changes in the levels of organic acids, sugars, amino acids, 5-hydroxymethylfurfural, among other compounds, while 25 cm² films appeared to induce only small variations. The observed metabolite variations were proposed to arise from the mitigation of fermentative processes, electrostatic interactions between acids and the positively charged films and the promotion of Maillard and Strecker reactions. Qualitative sensory analysis showed that wines maintained overall appropriate sensory characteristics, with 100 cm² film treated wines showing slightly higher attributes. Based on these results, the possibility of using Ch-Ge films as a replacement for SO₂ treatment is discussed. Full article

This study evaluated the effects of sodium alginate, pectin and chitosan addition (0.5–1.5%) on the physicochemical properties including pH, water activity, moisture content, color values, hardness, diameter, thickness, spread ratio, antioxidant activities and sensory scores of biscuits in air frying processing. In addition, the formation of acrylamide and hydroxymethylfurfural (HMF) were discussed. Physicochemical properties of biscuits including water content, water activity, hardness, appearance, shape, color, flavor, texture, overall acceptability, and DPPH radical scavenging activity of biscuits were not influenced significantly by the addition (0.5–1.0%) of three food hydrocolloids. The data showed that the biscuits with hydrocolloids addition had lower acrylamide contents than that of the control biscuit without hydrocolloids addition, and the reducing power of biscuits increased after adding the hydrocolloids. The highest mitigation of acrylamide formation was obtained by the chitosan addition formulation. The formation of acrylamide showed a negative correlation with the content of sodium alginate and chitosan addition, and they were effective ingredients in terms of mitigating the formation of acrylamide in biscuit formulation. Full article

Maillard reaction during food processing contributes to the formation of some unpleasant heat-induced toxicants including advanced glycation end products (AGEs) and 5-hydroxymethylfurfural (HMF). The current study prepared butter cookies fortified with two dietary natural antioxidants (catechins and curcumin) and two dietary hydrocolloids (pectin and chitosan), and investigated their effects on formation of free N^ε-(carboxymethyl)lysine (CML)/N^ε-(carboxyethyl)lysine (CEL), protein-bound CML/CEL and HMF and on the sensory qualities of butter cookies. Meanwhile, three typical α-dicarbonyl compounds were also determined to identify possible correlations between α-dicarbonyl intermediates and formation of these harmful heat-induced products in butter cookies. Experimental data showed that catechin exhibited the strongest inhibitory effects on formation of AGEs and HMF, but its addition would impair the color and taste of cookies. On the other hand, chitosan was not so effective in inhibiting AGEs and HMF as compared to catechin, but its addition could increase the sensory qualities of butter cookies. Full article

A 2k factorial design with three centrals points was considered to evaluate the effect of adding red Tara pods extract (Caesalpinia spinosa) (440–2560 µg/mL of dough water) and NaCl (0.3–1.7 g/100 g of flour) on the acrylamide (AA) and hydroxymethylfurfural (HMF) content and sensory attributes of crackers. Additionally, the best formulation, defined as that with the lowest AA and HMF content, was compared with a commercial formulation cracker. Red Tara pods extracts were obtained through conventional extraction using pure water (60 °C, 35 min). AA and HMF content were quantified by GC-MS and HPLC-DAD, respectively. The sensory evaluation was carried out using a descriptive analysis on a 10 cm non-structured linear scale. Red Tara pods extract significantly reduced (p < 0.05) the AA and HMF content, while NaCl only influenced the HMF formation. However, the sensory attributes did not significantly change (p > 0.05), excepting the violet-gray color and salty flavor, but at acceptable levels compared with the control sample. The higher the red Tara pods extract concentration (2560 µg/mL of dough water), the lower the neo-formed contaminants (NFCs) content of crackers (AA: 53 µg/kg and HMF: 1236 µg/kg) when salt level was below 3 g/100 g of flour. The action of the proanthocyanidins present in the extracts which trapped the carbonyl groups of sugars probably avoided the formation of both NFCs. Contrarily, NaCl addition (from 0.3 to 1.7 g/100 g of flour) significantly increased (p < 0.05) the HMF formation (from 1236 µg/kg to 4239 µg/kg, respectively), probably through the dehydration of carbohydrates during the Maillard reaction. When explored treatments were compared with a commercial formulated cracker, the highest mitigation effect (reductions of 40% and 32% AA and HMF, respectively) was reached with the addition of 2560 µg/mL of dough water of red Tara pods extract and 0.3 g/100 g of flour of NaCl. The addition of red Tara pods extracts integrated with the control of NaCl levels mitigated the NFCs in crackers, preserving their sensory properties. Future research should be focused on scaling this mitigation technology, considering a better chemical characterization of red Tara pods extracts as well as the validation of its use as functional food ingredient. Full article

The current trend of lowering 5-hydroxymethylfurfural (5-HMF) dietary exposure is challenging since its formation is parallel with the development of food color, flavor and aroma. We aimed to investigate the effect of gallic acid (GA) addition on 5-HMF formation, color development and antioxidant activity (AA) in a series of Maillard Reaction (MR) model systems. The effects of GA addition on browning and AA development were not uniform for all model systems, but always occurred in the same direction, indicating that these phenomena were interconnected. GA mitigated 5-HMF development in four of the nine tested systems, possibly by preventing the oxidation of MR intermediates. Correlation analysis indicated that when GA addition mitigated 5-HMF formation, browning was either promoted or not affected. The proposed strategy was effective for glucose/arginine and sucrose/arginine systems, since GA mitigated 5-HMF formation (49% and 54%, respectively) in addition to increasing color development and antioxidant activity. Full article