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Watermelon juice is a nutritious yet highly perishable beverage. Conventional thermal pasteurization ensures safety but degrades heat-sensitive nutrients, color, and flavor. Induced electric field (IEF) is an emerging technology that inactivates microorganisms while better preserving quality. However, its effects on the comprehensive quality retention of watermelon juice during storage remain underexplored. This study investigated the efficacy of IEF treatment on the microbial inactivation and quality preservation of watermelon juice during 25 days of storage at 4 °C. Freshly extracted watermelon juice was subjected to low-temperature IEF at 65 °C (IEF1) for 101 s and 60 °C (IEF2) for 88 s, with conventional pasteurization (65 °C, 30 min) as a control. The results showed that no colonies were detected in the IEF2 group throughout the 25-day storage period. Both IEF treatment and pasteurization effectively inhibited juice acidification. Soluble solids content and electrical conductivity remained stable under refrigeration, and the IEF group showed slower and more controllable acidity on day 25. Notably, the IEF1 group retained the highest lycopene content at the end of storage, while the IEF2 group maintained the highest total phenolic content (TPC). Furthermore, IEF treatment effectively mitigated color deterioration and preserved carbohydrate stability during refrigeration. Flavor analysis revealed that the taste profile of the IEF2 group at the initial storage stage closely resembled that of fresh watermelon juice. Over the 25-day period, the relative content of key volatile compounds characteristic of fresh watermelon decreased by only 3.64% in the IEF2 group. Full article

Consumers believe that expired products are unsafe, and, in most cases, misinterpreting the information on food labels often leads to large amounts of food waste. Yogurt is among the most widely eaten dairy products that can still be consumed after its expiration date, even though most consumers throw it away the very day it expires. The aim of this study was to determine whether commercial yogurts currently available on the market remain safe for consumption after their expiration date, with a view to reducing the amount of food waste generated in households. Therefore, the quality, stability, and edible safety of 10 commercial yogurts (two plain with 2% and 4% fat and the others with fruit, such as apricots, strawberries, bananas, blueberries, berries and strawberries, blackberries and raspberries, and cherries) stored at 4°C before and at the expiration date were investigated. Physicochemical, textural, microbiological, and sensory analyses were performed to evaluate changes in functionality, safety, and acceptability of these yogurts. The results showed that, prior to their expiration date, certain yogurt samples (with apricots, strawberries, and blueberries, as well as plain yogurt with 4% fat) tested positive for total coliform bacteria, with values ranging from 20 to 50 CFU/g, suggesting substandard hygiene practices and insufficient sanitary conditions during and following the production process. No Escherichia coli, Listeria, Salmonella, Enterobacter spp., or Enterococcus spp. were detected in any of the yogurt samples that were within their expiration date. Blueberry, berry, and strawberry yogurts change their physical and chemical properties less than other types of yogurts analyzed after expiration. Yogurts containing berries and strawberries, blackberries, and raspberries remain safe at the expiration date, as they do not show the presence of harmful microorganisms such as coliform bacteria, Escherichia coli, Enterobacter spp., Enterococcus spp., Listeria, or Salmonella. Yogurt with berries and strawberries appears to be the most suitable from a microbiological point of view at expiration, as it has a low total mesophilic bacteria count and lactic acid bacteria exceeding 1 × 10⁶ CFU/g. At the time of expiration, this fruit yogurt type (with berries and strawberries) had a total solids content of 21.29%, 5.22% protein, 2.11% fat, 13.19% carbohydrates, 4.07 pH, 26.79% syneresis, 73.21% water retention capacity, 64.78% total phenolic content, and 10.55% DPPH (inhibition percentage). Nevertheless, at the time of expiration, from a sensory perspective (only appearance and consistency, odor, and color, without taste), the yogurt samples that were most appreciated contained blackberries and raspberries. The obtained results indicate that only certain types of fruit yogurts stored unopened at 4 °C may remain safe and edible after the expiration date, but further studies are needed to help the dairy industry and policymakers promote the reduction in food waste in households. Full article

Consumer interest in low-SO₂ white wines is increasing; however, such approaches may reduce compositional and sensory predictability. This study evaluates how three fermentation strategies—SO₂ addition and Saccharomyces cerevisiae ES181 inoculation (SO₂Sc), spontaneous fermentation (NoSO₂-Spont), and inoculation with S. cerevisiae ES181 without SO₂ addition (NoSO₂Sc)—shape the chemical profile, polyphenolic composition, colour, microbiological status, and sensory perception of ‘Solaris’ wines relative to the must (reference). A single batch of ‘Solaris’ must (one press run) was split into three variants and fermented under identical temperature conditions (12 ± 0.5 °C), followed by cool ageing and natural sedimentation prior to bottling. Basic oenological parameters, selected fermentation by-products, viable yeast counts, CIE Lab colour, targeted polyphenolics (phenolic acids, flavonols, flavan-3-ols, and stilbenes), PCA of by-products, and blind sensory evaluation were assessed. The NoSO₂-Spont variant showed reduced fermentation completeness (higher residual sugars and lower ethanol) and the highest volatile acidity, together with elevated glycerol and several higher alcohols, and received the lowest sensory ratings. The SO₂Sc variant yielded the most controlled outcome, with the lowest volatile acidity, the brightest colour (higher L*, lower b*), and the highest sensory acceptance. The NoSO₂Sc variant produced intermediate sensory scores and a higher total phenolic content; however, volatile acidity remained high and viable yeast counts were the greatest, indicating increased susceptibility to microbiological activity during extended pre-bottling handling. Overall, the SO₂Sc strategy provides the greatest chemical stability and sensory acceptance, whereas low-SO₂ regimes require a hurdle approach (oxygen control, residual sugar management, hygiene, and stabilisation) to limit spoilage development and post-bottling refermentation. Full article

Cajanus cajan (L.) Huth (Fabaceae) is a food legume of considerable nutritional and functional significance. This study examined the comparative effects of salt stress on seed germination, hydroponic growth, and phytochemical accumulation across two developmental stages: 10-day-old germinated seeds and 45-day-old hydroponically grown plants, using NaCl solutions at concentrations of 0, 25, 50, 75, 100, and 150 mM. Both germination rate and growth were greatest at 0–25 mM NaCl, with performance declining at higher concentrations. LC–MS/MS analysis of free amino acids in 10-day-germinated seeds revealed a salt-induced metabolic shift. Proline, leucine, and phenylalanine were the dominant free amino acids and increased progressively with rising NaCl concentrations. Phytochemical profiling by HPLC identified gallic acid, catechin, and genistin as the major compounds, with increased levels under salinity stress. Germinated seeds at 150 mM NaCl, germinated seeds exhibited the highest phytochemical accumulation, with total phenolic content (TPC), total flavonoid content (TFC), and DPPH activity reaching 18.192 ± 0.020 mg GAE/g extract, 8.519 ± 0.026 mg QE/g extract, and 11.623 ± 0.284 mg AAE/g extract, respectively. Phytochemical responses in 45-day hydroponic plants varied by tissue type. Leaves exhibited declining TPC and TFC with increasing NaCl (from 29 to 16 mg GAE/g and 41 mg QE/g extract), while stems showed the opposite trend, reaching 18 mg GAE/g and 21 mg QE/g extract at 50 mM. Root tissues maintained comparatively low phytochemical levels throughout. Notably, DPPH scavenging capacity increased across all tissues under salt stress, with peak values of 12–13 µg AAE/g extract recorded at 50 mM NaCl. These results indicate that salt stress exerts stage- and organ-dependent effects on phytochemical accumulation in C. cajan. High salinity during germination stimulates bioactive compound production, whereas moderate salinity appears to be the threshold at which antioxidant capacity is maximized in hydroponic systems. These observations point to the practical utility of controlled salt elicitation as a strategy for enriching pigeon pea with health-promoting phytochemicals, reinforcing its potential as a functional food crop. Full article

In the sustainability framework, valorization of organic by-products as reservoirs of phytochemicals useful for human health represents a hot topic. Therefore, this study evaluated Norway spruce bark and twigs (NSB, NST), chestnut tree wood (CTW), and pomegranate fruit waste/pomace (PFW) as sources of bioactive compounds by employing green technologies. Microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE), applied individually or sequentially, were optimized by modulating solvent composition, temperature, time, microwave power, and ultrasound amplitude. Hydroalcoholic extraction (50% ethanol) combined with MAE yielded the highest phenolic recovery and antioxidant activity across all matrices. PFW exhibited the highest antioxidant activity assessed through FRAP, ORAC, and DPPH assays. Phytochemical profiling by HPLC-DAD identified stilbenes in spruce extracts, ellagic acid in chestnut wood, and ellagic acid and punicalagins in pomegranate waste as major bioactive constituents. Additionally, NSB and PFW exhibited α-amylase inhibitory activity. Antimicrobial testing demonstrated dose-dependent activity against Gram-positive (Staphylococcus epidermidis and Bacillus subtilis) and Gram-negative (Pseudomonas stutzeri) strains, with PFW exhibiting the strongest inhibition and NSB displaying broad-spectrum effects. Total phenolic content changed moderately after 21 days of storage. These results demonstrate that sustainable extraction enables efficient recovery of bioactive compounds from plant by-products, supporting their further functional, dietary, and medicinal applications. Full article

The growing need for sustainable strategies to reduce agro-industrial waste has stimulated interest in valorizing winery by-products as sources of high-value bioactive compounds. Wine lees, rich in phenolic compounds with well-documented antimicrobial activity, remain largely underutilized in the development of functional materials. In most cases, incorporation of bioactive agents relies on physical adsorption, which often results in weak adhesion and limited durability. In this study, phenolic extracts derived from wine lees and grape seed extract were incorporated into bacterial cellulose (BC) to develop bioactive materials with antimicrobial and antioxidant functionality. Two strategies were investigated: (i) direct immersion of BC in phenolic extracts and (ii) incorporation of extracts in BC membranes pre-modified with carboxymethyl cellulose (CMC) to enhance phenolic affinity and retention. The resulting materials were characterized for total phenolic content, antioxidant activity, and antimicrobial performance against bacterial strains (Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus). CMC-pretreated membranes significantly enhanced phenolic incorporation and antimicrobial performance, achieving a 99.9% reduction in E. coli after 24 h, while S. Typhimurium and S. aureus counts were below the detection limit (LOD < 1.0 log₁₀ CFU/mL). These findings demonstrate the potential of wine lees as a sustainable source of bioactive compounds for the development of antimicrobial cellulose-based materials, supporting circular bioeconomy strategies and their potential application in food packaging. Full article

This study evaluates the potential of marc, a by-product of clitoria (Clitoria ternatea L.) and borage (Borago officinalis L.) infusions, as a preliminary step toward their subsequent conversion into functional food ingredients. After infusion, the marc was collected and processed by carrier-assisted crushing, aqueous maceration, and subsequent separation into extract and residue fractions. The impact of flower pretreatment by milling and marc matrix modification by inulin and maltodextrin was studied on the physical (dry matter (DM), water activity, color), chemical (total phenolic content (TPC), sum of individual phenolic compounds, and antioxidant capacity), and solubility of the microencapsulated fractions. Inulin-formulated powders derived from intact flowers’ marc were characterized by higher dry matter, decreased water activity, and improved chemical profiles. Under these conditions, clitoria by-products exhibited mean dry matter 94.17 ± 0.20%, water activity 0.301 ± 0.003, TPC 3.285 ± 0.052 mg GAE/g DM, sum of individual phenolic compounds 6.267 ± 0.103 mg/g DM, and ABTS-determined antioxidant capacity 0.100 ± 0.001 mmol Trolox/g DM. For borage by-products under identical conditions, dry matter content (−1.60%), water activity (−12.62%), TPC (−39.82%), sum of individual phenolic compounds (−67.55%), and antioxidant capacity (−65.00%) were lower compared with clitoria by-products. An efficient extraction and stabilization approach can open opportunities for upcycling post-extraction herbal residues into high-value food ingredients. Full article

Efficient recovery of phenolic compounds from citrus processing by-products requires optimized solvent systems and reliable frameworks for comparing emerging extraction technologies. In this study, a solvent system was first optimized to maximize phenolic recovery from lemon (Citrus limon (L.) Burm. f.) processing by-products, enabling a standardized comparison of ultrasound-assisted extraction (UAE) and hydrodynamic cavitation (HC). A preliminary solid–liquid extraction screening using different water:ethanol ratios (v/v) identified a 50:50 hydroalcoholic mixture as the optimal solvent system for recovering phenolic compounds. HPLC analysis confirmed the presence of major flavanones (eriocitrin and hesperidin) and hydroxycinnamic acids (caffeic, p-coumaric, sinapic, and ferulic acids). Antioxidant capacity was assessed using complementary assays (Folin–Ciocalteu, DPPH, and ORAC) to provide a comprehensive evaluation of antioxidant activity. Under optimized solvent conditions, UAE significantly improved the recovery of total flavanones (+25.9%), hydroxycinnamic acids (+10.3%), total polyphenols (+20.5%), DPPH activity (+6.0%), and ORAC values (+9.6%) compared with conventional extraction. HC further enhanced extraction performance, increasing flavanone recovery by 12.0%, hydroxycinnamic acids by 7.2%, total polyphenols by 5.2%, and antioxidant activity (DPPH and ORAC) by 11.4% and 2.0%, respectively, relative to UAE. Following ethanol removal and concentration, HC-derived extracts showed the highest phenolic content and antioxidant capacity. These results demonstrate that solvent optimization, combined with a standardized comparison of extraction technologies, enhances phenolic recovery from lemon processing by-products. The findings indicate that HC is a promising, scalable approach for the sustainable recovery of bioactive compounds from citrus side-streams. The novelty of this work lies in the integration of solvent optimization with a systematic and standardized comparison of UAE and HC, providing a reproducible framework for evaluating emerging extraction technologies and highlighting the enhanced performance and scalability potential of HC for phenolic recovery from citrus processing by-products. Full article

In this study, we compared the effects of microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE) on the total phenolic content, antioxidant activity, morphological characteristics, and tentative identification of bioactive compounds by LC-ESI-MS/MS in pomegranate seeds. We conducted a phytochemical characterization of the extracts by determining the total phenolic content and total flavonoids. Antioxidant activity was evaluated using ferric-reducing antioxidant power (FRAP) and free radical inhibition methods (DPPH and ABTS). Morphological characteristics were analyzed via scanning electron microscopy, UV-Vis and FTIR of the extracts were recorded. Additionally, the main bioactive compounds were identified using HPLC-MS. Our results demonstrated that MAE was the most efficient technique, yielding a higher content of total phenols (35.47 mg GAE/g), total flavonoids (14.44 mg CAE/g) and antioxidant activity (0.19 and 0.41 mmol TEAC/g, as determined by FRAP and ABTS, respectively). In terms of morphological characteristics, UAE induced more changes in the structure of the plant material compared to MAE. According to HPLC-MS analysis, the extract obtained using MAE notably contained coumaric acid, cyanidin, and quercetin, whereas the UAE extract included coumaric acid, cyanidin, kaempferol, and epicatechin. In conclusion, this study demonstrated that MAE is a more efficient method than UAE for extracting bioactive compounds. Pomegranate seeds may represent a potential source of these compounds for application in various industrial areas. Full article

Cocoa fermentation is a key post-harvest process that determines the chemical composition and functional quality of cocoa beans. This study evaluated the effect of enzyme-assisted fermentation, using bromelain and laccase, on the phenolic compounds, methylxanthines and antioxidant capacity of CCN-51 cocoa beans from northern Peru. Fresh cocoa beans were fermented in wooden boxes under ambient conditions with different enzymatic treatments based on a factorial design. Samples were collected at 0, 2, 4 and 6 days of fermentation to determine total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (DPPH, ABTS and FRAP), and the concentrations of theobromine, caffeine, catechin and epicatechin by UHPLC-MS. Significant changes in phenolic composition and antioxidant activity were observed during fermentation (p < 0.05), with higher values in enzyme-treated samples, particularly at day 4. Principal component analysis indicated that phenolic compounds and antioxidant activity were the main variables responsible for sample differentiation. Response surface methodology showed that bromelain had the strongest influence on most responses. Optimization using a desirability function predicted an optimal enzymatic condition of 52.19 g of bromelain and 18 g of laccase per 5 kg of cocoa beans to maximize bioactive compounds. These findings highlight that enzyme-assisted fermentation is a promising strategy to enhance cocoa functional quality. Full article

Green husks, which are the fleshy pericarp of Juglans regia L. fruit, are an abundant yet under-utilized source of bioactive compounds. They are useful for plant defense and have potential for valorization to multiple commercial products. This study characterized total phenolic content (TPC) and individual phenolics in green husks of four Hungarian-bred cultivars (Milotai 10, Milotai intenzív, Milotai kései, Esterhazy kései) and one U.S. cultivar (Chandler). Phenolic compounds were extracted with aqueous organic solvents, quantified by HPLC-DAD and qualitatively identified by HPLC-MS. Linear mixed-effects models were used to assess the effects of cultivar, year, sampling time, and cumulative growing degree days (GDDs) on TPC and compound profiles. Mean TPC ranged from 34.9 to 57.2 mg GAE g⁻¹ DW, with significantly higher values in the warmest year, 2024, and in cultivar Esterhazy kései compared with Chandler. Across cultivars and years, phenolic levels were generally elevated at early lignification (S1, BBCH 73–75) and at full maturity (S5–S6, BBCH 87–88), with depressed concentrations during mid-fruit development (S2–S4, BBCH 77–86). Several hydroxycinnamic acids, flavonoids, and naphthoquinones showed cultivar-specific and year-dependent patterns. Thermal conditions (cumulative GDDs) explained a substantial proportion of residual variation in TPC. These results highlight the combined roles of genotype, seasonal climate, and developmental stage dependencies in biosynthetic processes of phenolics in walnut green husks despite the diversity in factor effects. Full article

Polyphenols and aroma compounds are major contributors to wine quality and are primarily derived from grape skins and seeds. This study investigated the effects of crushing degree and maceration time on the phenolic and aroma profiles of Cabernet Sauvignon wine. Wines were produced under different crushing degrees (50–100%) and maceration times (5–13 d), and their phenolic and aroma compounds were analyzed by ultraviolet–visible spectrophotometry (UV–Vis) and gas chromatography–mass spectrometry (GC-MS). The results showed that both crushing degree and maceration time significantly affected the extraction and accumulation of these key compounds. A crushing degree of 70–80% combined with 7–9 d of maceration was more suitable for producing wines with a balanced color, aroma, and taste profile. In contrast, complete crushing (100%) and 11 d of maceration were more favorable for enhancing antioxidant potential, with flavanol and total phenol contents reaching 346.6 and 115.9 mg/L, respectively. These findings provide a theoretical basis for optimizing vinification conditions and improving wine quality to meet diverse consumer preferences. Full article

Apples (Malus domestica Borkh.) are among the most widely consumed fruits worldwide and represent a significant dietary source of phenolic compounds. Efficient extraction is a critical step for the isolation, characterization, and quantification of phenolic compounds. The extraction yield and composition are strongly influenced by multiple parameters, including solvent type and concentration, temperature, extraction time, solid-to-liquid ratio, and the presence and concentration of acidifying agents. This study aimed to optimize an ultrasound-assisted extraction (UAE) procedure using response surface methodology (RSM) to evaluate the effects of extraction temperature, solvent-to-sample ratio (SSR) and citric acid concentration on total phenolic content (TPC) and total flavonoid content (TFC). Statistical analysis showed that SSR and temperature were the most influential factors affecting phenolic recovery, while citric acid concentration exerted a secondary, interaction-driven effect. Optimization using a desirability function identified the operating conditions that maximized phenolic and flavonoid recovery: 55 °C, 10 mL/g SSR and 0.2% citric acid concentration. Model predictions were validated experimentally, confirming the reliability of the approach for TPC and TFC. Chlorogenic acid and flavan-3-ols, including monomers, such as catechin and epicatechin, and polymers such as procyanidins, were identified. Overall, the proposed approach provides a statistically supported framework for phenolic compound analysis in apples. Full article

This study evaluates the impact of recirculating aquaponic cultivation on the biochemical, mineral, and antioxidant profiles of Swiss chard (Beta vulgaris var. cicla) integrated with Nile tilapia (Oreochromis niloticus), which serves as a source of nutrients through metabolic waste transformation within the system. Water quality parameters and microbiological testing confirmed efficient nitrification and system safety, with no Escherichia coli detected. Results showed that aquaponic cultivation yields a high nutritional value of Swiss chard, yielding high crude protein (31.4% DW) and mineral-rich biomass (ash 22.8% DW). Substantial concentrations of essential elements were recorded, including Ca, Mg, Fe (253.7 mg/kg DW), Zn, and Cu, suggesting high ionic bioavailability in the recirculating system. Physiological stability was reflected by a chlorophyll a content of 4.74 mg/g DW. Furthermore, the plants exhibited a robust phytochemical profile, with total phenolics (4.13 mg GAE/g DW) and flavonoids (5.18 mg QE/g DW) driving strong antioxidant activity (93.1% ABTS inhibition). These findings demonstrate that integrated aquaponic systems function as effective nutrient bioreactors, supporting high plant functional quality while supporting sustainable food production. The results validate aquaponics as a viable, climate-smart strategy for high-quality leafy vegetable cultivation within a circular bioeconomy framework. Full article

The increasing awareness of health among consumers has made the development of functional cereal products a major trend in the food industry. This study investigated the effects of grape seed extract (GSE) on the quality parameters of medium-gluten wheat flour and fresh wet noodles, with the aim of developing functional noodle products. GSE was incorporated at concentrations of 0%, 0.2%, 0.4%, 0.6%, and 1% (w/w). Its influence on dough properties—including farinographic characteristics, extensibility, and pasting behavior—as well as on noodle quality attributes (antioxidant activity, tensile strength, color, microstructure, total phenolic content, and sensory profile) was evaluated. The results indicated that at 1% GSE addition, the farinographic properties, extensibility, and pasting characteristics of the dough were consistently enhanced. Correspondingly, the noodle microstructure exhibited a more compact and ordered arrangement. Furthermore, increasing the level of GSE fortification led to a significant rise in the total phenolic content and antioxidant capacity of the noodles (p < 0.05). This study can provide key technical support for developing novel fresh wet noodle products that possess both excellent quality and antioxidant functionality, thereby contributing to the functional enhancement of staple food products and meeting consumer demand for healthier dietary options. Full article