Search Results (504)

Lyophilized pectinase from Aspergillus niger (PeL) was immobilized onto polyamide 6 (PA6) microparticles (MPs) through an adsorption-based procedure within the pH range of 5–8, yielding four PeL@PA6 complexes. In contrast to commercial enological preparations that are complex enzymatic cocktails with unspecified exact compositions, the use of PeL with known specific activity enabled a more reliable evaluation and improvement of the immobilization process and of the structure–activity relationships of the resulting biocatalysts. Thermogravimetric analysis demonstrated better thermal stability of the PeL@PA6 complexes compared to neat PA6 MPs. UV-CD studies revealed that the secondary structure and conformational stability of PeL before and after immobilization were strongly pH-dependent, with maximum stability observed at pH 6–7. All four PeL@PA6 complexes retained significant catalytic activity and showed good tolerance to ethanol-rich media relevant to enological applications. Kinetic analysis indicated increased apparent K_m values after immobilization, suggesting diffusional limitations associated with the porous PA6 support. Clarification experiments of industrial white and rosé wine musts confirmed the practical applicability of the immobilized system. All PeL@PA6 complexes preserved the color and phenolic integrity of the musts, displayed good operational stability during reuse, and exhibited higher long-term storage stability than the free enzyme. These results demonstrate that PA6 MPs are promising supports for pectinase immobilization in wine clarification and related biotechnological applications. Full article

Microplastics (MPs) have been reported in commercial beverages, but substantial differences in study design make direct comparisons difficult. This non-systematic, focused narrative review critically synthesizes a purposively selected core set of 17 particle-count studies published from 2020 to 2026 on soft drinks, beer, wine, tea, coffee, juices, energy drinks, and related beverages, while considering recent complementary thermal-analysis evidence. Data were compared for study location, beverage type, analytical method, abundance, particle size, morphology, color, polymer composition, and packaging. Fourier-transform infrared spectroscopy-based methods were most common; Raman spectroscopy, fluorescence microscopy, scanning electron microscopy, and laser direct infrared imaging were used in selected studies. Reported soft-drink concentrations ranged from approximately 0.30 particles/L to 166 ± 62 particles/100 mL (1660 ± 620 particles/L), but these values cannot support a geographic ranking because minimum particle-size thresholds, confirmation criteria, blank corrections, sample volumes, and reporting units differed. Fibers and fragments were the dominant morphologies, and polyethylene terephthalate, polyethylene, polypropylene, and polyamide were frequently identified. Findings from beverages packaged in glass and aluminum, as well as plastic, indicate that source water, ingredients, processing equipment, filtration, closures, ambient deposition, and packaging can all contribute. Current intake estimates describe potential particle ingestion rather than absorbed dose or toxicological impact. Because current data largely reflect analytical sensitivity rather than true contamination gradients, this review demonstrates that reliable cross-study exposure assessments currently remain associated with considerable uncertainty, and this uncertainty will be difficult to resolve until particle-count data are normalized to harmonized size thresholds and paired with mass-based thermal analyses. Full article

This study evaluated the effects of thermocycling and staining on the optical behavior, chemical stability, and surface morphology of three commercial dental composites manufactured using different polymerization protocols: a light-cured composite (Omnichroma, OMNI) and two digital light-processed (DLP) 3D-printed composites intended for permanent (SprintRay CROWN, SPRINT) and temporary (GC Temp PRINT, TEMP) clinical applications. Disc-shaped specimens were subjected to thermocycling (0, 5000, 10,000, and 30,000 cycles) and immersion in coffee, Coca-Cola, or red wine for 1 and 7 days. Color change (ΔE₀₀) and translucency parameter (TP) were determined spectrophotometrically, while Fourier-transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM) were employed to assess the polymerization efficiency (expressed as the relative conversion index) and surface morphology, respectively. Thermocycling induced material-dependent changes in color stability and translucency. After 30,000 cycles, ΔE₀₀ values reached 2.77 ± 0.89 for OMNI, 0.74 ± 0.34 for SPRINT, and 3.30 ± 0.89 for TEMP. SPRINT maintained the highest TP values throughout the aging protocol, ranging from 26.09 ± 0.33 to 23.81 ± 1.93, whereas OMNI and TEMP exhibited lower TP values. The most favorable optical performance and the highest resistance to beverage-induced coloration were detected for SPRINT, whereas TEMP showed the greatest susceptibility to aging- and staining-induced optical degradation. Red wine and coffee produced substantially greater color changes and reductions in translucency than Coca-Cola. AFM analysis demonstrated progressive surface degradation and increased roughness following prolonged thermocycling, highlighting the significant influence of material composition and manufacturing protocol on the long-term optical stability of the investigated dental composites. Full article

Co-fermentation of tea and wine offers a promising route to functional beverages with enhanced sensory complexity and potential health benefits. We co-fermented Marselan (Vitis vinifera L.) grapes with Fu brick tea (0, 0.5, 1.0, 1.5 g/L), a post-fermented tea containing the probiotic fungus Eurotium cristatum. We systematically examined how tea-derived phenolics modulate wine color and aroma. Fu tea addition progressively decreased alcohol (12.24% → 10.86%) and modestly reduced residual sugar, while volatile acidity remained stable, indicating no adverse fermentation impact. HPLC revealed a substantial increase in tea-derived phenolics; chlorogenic acid nearly doubled and became the dominant phenolic compound. CIELab color analysis showed increased lightness (L) and marked decreases in yellow hue (b) and hue angle (h°). Total phenolic content correlated negatively with h° (r = −0.656, p = 0.0205), suggesting that the overall phenolic load—not any single compound—is associated with the shift toward a more stable brick-red hue. PCA showed that chlorogenic acid contributed to both color (PC1) and phenolic (PC2) variation. GC-MS revealed substantial increases in esters and higher alcohols, and the emergence of 1-octen-3-ol, a characteristic metabolite of E. cristatum. C6 compounds associated with herbaceous aromas decreased significantly. Fu tea co-fermentation thus enhanced wine color stability and aroma complexity through a multifaceted phenolic network. Under our conditions, 1.0 g/L Fu tea gave the most favorable balance of color stability and aroma complexity. These findings provide a preliminary theoretical basis for developing tea-wine products, though further mechanistic studies are needed to establish causality. Full article

Objective: The effect of incorporating various concentrations of 210 nm ZnO nanoparticles (ZnO-NPs) into resin-based composites (RBCs) and glass-ionomer cement (GIC) on their color and surface roughness after immersion in red wine is evaluated. Materials and Methods: 12 experimental groups (n = 12) were tested, including three commercial restorative materials: a microhybrid RBC (Gradia Direct^®), a nanohybrid RBC (Evetric^®) and a GIC (Fuji IX^®). These were modified with ZnO-NPs at weight concentrations of 1%, 2%, and 3%. Color coordinates (L*,a*,b*) were measured using a spectrophotometer (CIEDE2000 formula) before and after 24 h immersion in red wine (37 °C). Surface roughness (Ra) was analyzed using contact profilometry. Results: The addition of ZnO-NPs increased the lightness (L*) and decreased the a* values in all materials. In resin-based composites, even a 1% concentration of ZnO-NPs caused a color change above the clinical acceptability threshold (ΔE₀₀ > 1.8; observed values ranged from 3.2 to 8.0). After immersion in wine, all materials exhibited further discoloration (ΔE₀₀ up to 12.5 for composites). Surface roughness values increased from 0.42 μm (control composite) to 1.95 μm (3% ZnO-NP-modified GIC). Conclusions: Addition of ZnO-NPs influences the aesthetics and topography of restorative materials. Their concentration must be balanced to maintain visual and surface integrity. Full article

Maceration techniques like cold maceration before fermentation (CM) and skin-contact fermentation (SF) are widely used in winemaking. However, their application remains limited in white winemaking, representing an important objective for the production of diverse white wines. This study systematically investigated the impacts of CM and SF on phenolics, volatile aromas and sensory properties of Chardonnay and Italian Riesling wines in Yantai wine region. Both CM and SF significantly increased the total phenolic content, especially with gallic acid and quercitrin contents rising 11.65- and 10.02-fold in Chardonnay, as well as catechin and quercitrin increasing 9.05- and 10.82-fold in Italian Riesling under 100% SF. Moreover, 72 h CM and 100% SF showed higher volatile aroma contents in both wines compared to other CM and SF treatments. Esters, including ethyl octanoate, ethyl hexanoate and isoamyl acetate, contributed to the improved floral and fruity aromas in maceration-treated Chardonnay wines, whereas esters and terpenes drove the aromatic profile of Italian Riesling wines, with terpenes rising 1.67- and 3.27-fold after CM and SF. The two varieties differed in wine color, with Italian Riesling wines displaying a stronger yellow hue and reduced lightness under 72 h CM, 50% SF and 100% SF. Sensory evaluation by a panel containing seven trained assessors found that SF-treated wines exhibited more intense flavor and balanced taste and CM-treated wines showed more freshness. These findings provide theoretical support for tailored maceration to enhance varietal expression in the specific region and diversify white wine production. Full article

This study investigates color and surface alterations in neat and modified PEEK materials (10 × 3 mm, n = 140) immersed in various beverage solutions. Surface roughness (Ra) and color change (ΔE) were analyzed, supported by SEM and AFM evaluations. Specimens polished with 400–1200 grit sandpaper were measured via profilometry before a 30-day immersion in distilled water, coffee, tea, cola, and red wine (refreshed every 12 h). Post-immersion results indicated that material and solution types significantly influenced Ra and ΔE values (p < 0.05), with the TP group being the least affected. Statistically, tea caused the greatest discoloration. The GFP group exhibited the highest Ra, indicating inferior surface stability, whereas TP and CR groups remained below the 0.2 μm clinical threshold. Specifically, the TP group demonstrated the lowest Ra value. Although perceptible color changes occurred in all materials, a positive correlation was identified between material type and beverage solutions. SEM and AFM analyses confirmed the presence of surface micro-cracks and morphological irregularities. Full article

Pineapple glutinous rice wine is a popular fermented beverage, yet its flavor and quality remain highly affected by yeast strains. This study aimed to explore the effects of four commercial yeasts, namely La Raffinée (Ra), La Bayanus (Ba), La Délicieuse (De), and Angel wine yeast (AWY), on the quality of pineapple glutinous rice wine. Fermentation indices including Brix and alcohol content were dynamically monitored, while final wine samples were analyzed for color difference, sensory quality and aroma components by gas chromatography–ion mobility spectrometry (GC-IMS). Results showed that all yeasts had optimal fermentation efficiency, sugar-to-alcohol conversion, physicochemical properties and sensory quality at an addition level of 0.2 g/L. The 0.2 g/L De group achieved the optimal overall quality with an alcohol content of 10.01% vol, the highest ester content (22.55%) and the lowest acid content (12.18%), presenting a balanced flavor, prominent pineapple aroma and refreshing taste. In contrast, Ba led to higher acidity and Angel wine yeast contributed to greater sweetness. Overall, 0.2 g/L De yeast effectively coordinated pineapple aroma and glutinous rice wine characteristics, providing a practical reference for optimizing the production and quality improvement of pineapple glutinous rice wine. Full article

Background/Objectives: 3D printing of removable dentures and temporary crowns and bridges is currently one of the fastest-developing technologies in prosthetic dentistry. However, little is known about the effect of different beverage solutions on the strength and color of 3D-printed denture resins. The study aimed to determine the effect of coffee, red wine, 40% ethyl alcohol, and water (reference samples) on six 3D-printed denture resins (Denture 3D+ (Nexdent); Vita Vionic (Vita), Lucitone Digital Print 3D (Dentsply), DX Denture Flex (Dentex); Formlab Denture Base (Formlabs, Optiprint Dentona). Materials and Methods: Resin samples measuring 3.3 × 10 × 65 mm (144 total) and disks 1 × 20 mm (108 total) were produced using an Asiga printer. The printed materials were then stored in coffee, red wine and distilled water and vodka for 30 days. After this time, they were subjected to a flexural strength (FS) test and the measurement of color change (CC), and compared to reference samples measured before contact with the solutions. One- and two-way ANOVA were used for statistical analysis to compare samples before and after contact with the solutions. Results: The vodka solution affected the materials’ FS—the strength was reduced from 10% (Lucitone) to 88% (Detax). For the sample with the most significant FS reduction, the elastic modulus could not be determined. The largest CCs were observed for coffee (E = 22.66 ± 1.26), and red wine (E = 21.04 ± 0.70), whereas vodka had the least effect on CC (Lucitone E = 1.04 ± 0.41 and Form Labs E = 1.31 ± 0.85). Conclusions: 3D-printed resins are susceptible to the effects of commonly consumed substances, such as coffee, vodka, and red wine. When designing and manufacturing removable prosthetic restorations, it is necessary to carefully consider the dietary habits of patients and the materials from which the removable prosthetics are printed. Full article

Acidification and the application of exogenous tannins are well-established oenological practices designed to ensure wine stability and quality, playing a pivotal role to address the grape compositional imbalances associated with climate change. This study investigates precision enology techniques using a 2023 Sangiovese di Romagna, analyzing the interaction between pH modulation (3.2, 3.6, 3.8) and the addition of commercial grape seed tannins with varying medium degrees of polymerization (TanA: 3.1 mdp vs. TanB: 10.8 mdp). Following alcoholic fermentation, a full factorial design was implemented, including control batches (pH adjustment only). After a 40-day mild thermal treatment (T = 25 ± 1 °C) to simulate aging, results indicate that the high-mdp tannin (TanB) dominated color evolution regardless of pH, whereas the low-mdp tannin (TanA) effect was pH-dependent. Notably, a pH of 3.8 resulted in colloidal instability across all samples. The findings highlight the importance of customized protocols to mitigate climate-related challenges in winemaking. Full article

Pre-harvest foliar application of chitooligosaccharide (COS) was evaluated for its impact on the flavor quality of Cabernet Gernischt wines. COS was applied at the young berry (YB) and early veraison (EV) stages across the 2022 and 2023 vintages. Physicochemical parameters, phenolic compounds, color index, volatile composition, and sensory quality were systematically analyzed. In 2022, alcohol content and total acidity increased in both treatment groups, total phenols increased in the EV group but decreased in the YB group. In 2023, alcohol and acidity showed opposite trends between the two treatment groups, while phenolic compounds decreased. COS treatment increased wine lightness and yellow tone but reduced red tone and color saturation. In 2022 vintage, YB treatment increased total volatiles with 8.18% and terpenoids with 138.91%, while esters increasing by 34.72–53.60%. In 2023 vintage, total volatiles decreased by approximately 15%, with esters significantly decreasing by 26.60% (YB) and alcohols by 25.96% (EV), while fatty acids increased by 32.70% (EV). OPLS-DA identified key aroma compounds, including phenethyl acetate, ethyl caprate, heptyl acetate, and isoamyl acetate. Aroma wheel analysis showed that fruity and floral notes were enhanced in 2022 but reduced in 2023, with the EV stage consistently performing better. Overall, COS application at the early veraison stage represents a promising strategy for modulating wine flavor quality. Full article

Background: The influence of surface sealants on the color stability of composite resin restorations remains controversial. This in vitro study evaluated the effect of two surface sealants on the color stability of a nanohybrid composite resin exposed to staining beverages. Methods: Ninety specimens of Enamel Plus HRi Bio Function (BF2) composite resin were divided into three groups: without sealant, with Embrace™ WetBond™ Seal-n-Shine™, and with Ena Bond Seal. Specimens were immersed in black tea, Coca-Cola^®, red wine, orange juice, coffee, or distilled water for 40 h. Color measurements were obtained before and after immersion using the OptiShade colorimeter in accordance with the CIELAB color system. Results: Significant differences were observed according to both the staining solution and the surface sealant applied (p < 0.001). Red wine produced the highest color changes in all groups, while coffee and black tea also caused clinically perceptible discoloration. The Seal-n-Shine™ group exhibited the highest ΔE values and greater color variation compared with the control group. In contrast, the Ena Bond Seal group exhibited chromatic behavior closer to that of the unsealed composite resin. Conclusions: Color stability was significantly influenced by both the staining solution and the applied surface sealant. Full article

The valorization of winemaking by-products is a sustainable strategy consistent with circular bioeconomy principles and current public health priorities. This study aimed to evaluate residual oenological yeast sediment from local Moldovan grape varieties, Viorica and Fetească Regală, as a multifunctional ingredient and partial fat replacer in muffins. Sunflower oil was replaced with wine lees (WL) at 20%, 35%, and 50%, and the obtained products were analyzed in terms of physicochemical, nutritional, microbiological, colorimetric, and sensory characteristics. WL incorporation reduced the caloric value by up to 10% and decreased lipid content, while contributing to higher protein and dietary fiber levels. Moisture values remained within acceptable limits, whereas titratable acidity increased with the substitution level (p < 0.05). Muffin density showed a slight increase, and water absorption capacity improved markedly, reaching 269%, mainly due to the fiber-rich composition of WL. Color analysis indicated reduced lightness and increased redness, associated with yeast pigments and thermal reactions during baking. Microbiological results showed lower total viable counts with increasing WL addition; however, the 50% substitution level exceeded the permissible limits for yeasts and molds. Sensory evaluation indicated that the muffin with 20% WL was the most acceptable sample. Overall, WL may be considered a promising sustainable ingredient for developing reduced-fat muffins with improved nutritional value. Full article

This review aims to critically examine food industry by-products as potential sources of natural preservatives and to discuss how this evidence can be translated into adolescent food literacy, label interpretation, and critical food choices. Adolescents are increasingly exposed to food labels and claims about “natural,” “clean-label,” “upcycled,” “sustainable,” and “circular” foods, which may not always be transparent or supported by sufficient evidence regarding their safety, efficacy, sensory quality, consumer acceptance, or environmental benefit. Therefore, they need more than nutritional information; they need to interpret labels, question sustainability claims, and understand how food innovations are produced, tested, communicated, and regulated. Food by-products such as fruit and vegetable pomaces, peels, seeds, skins, olive and wine residues, cereal by-products, coffee silverskin, and cocoa residues are promising resources for clean-label preservation and circular food systems because they may contain phenolics, flavonoids, carotenoids, anthocyanins, essential oils, pectin, dietary fibers, and other compounds with antioxidant, antimicrobial, coloring, stabilizing, and texturizing properties. However, the bioactive potential alone does not guarantee that a by-product-derived ingredient is safe, effective, acceptable, scalable, or sustainable. Its use requires extraction, stabilization, real-food validation, safety assessment, sensory optimization, regulatory compliance, and sustainability evaluation. The review concludes that by-product-derived natural preservatives are both technological resources and educational tools. Future research and education should connect food preservation, label interpretation, food safety, sensory quality, sustainability evidence, and consumer decision-making to empower adolescents as critical consumers and informed agents of change in sustainable food systems. Full article

Developing an environmentally friendly material with dual functionality of corrosion monitoring and inhibition is crucial for reducing economic losses. Herein, dual-function phytic acid carbon dots (PA-CDs) were prepared with a hydrothermal treatment method for corrosion monitoring and inhibition. The as-prepared PA-CDs exhibited a distinct color change from brown-yellow to wine-red immediately in the presence of OH⁻, and H⁺ can restore the color of the PA-CDs-OH⁻ system from wine-red to brown-yellow. Inspired by the above phenomenon, a visible RGB-based colorimetric sensor was fabricated by combining PA-CDs coatings with the self-made RGB-sensing device to detect OH⁻/H⁺ during metal corrosion. In addition, PA-CDs had excellent corrosion inhibitory properties for Q235 steel hanging sheets in hydrochloric acid solutions, and the corrosion inhibition efficiency reached 96.40%. The excellent corrosion monitoring and inhibition properties demonstrate the potential application of the PA-CDs in engineering practice. Full article