Search Results (505)

Background: Biostimulants naturally improve plant growth, stress tolerance, and nutrient use efficiency and activate defenses by increasing protective metabolites (phenols, anthocyanins) in grapes. In viticulture, especially when using inactive yeasts, they modulate genetic expression and improve the skin resistance, color, and aroma profile of wine grapes in line with sustainable practices. Methods: Two wine grape cultivars, Merlot and Cabernet Sauvignon, were sprayed with the inactive yeast Saccharomyces cerevisiae in a single treatment in pre-veraison or in a double treatment in pre-veraison and veraison. Berry weight, must, total polyphenols, anthocyanins, and mechanical and colorimetric properties were measured on fresh grapes. Results: Two-way ANOVA revealed that titratable acidity (TA), pH, and total polyphenol content (TPC) were not affected, while mean berry weight and anthocyanin content varied by cultivar, treatment, and interaction; total soluble solids (TSS) differed only by cultivar. Inactive yeasts reduced weight in the single-treatment thesis but stabilized it in the double-treatment one; anthocyanins decreased in Cabernet Sauvignon but increased in Merlot. Mechanical and colorimetric analyses showed cultivar-dependent responses, with significant improvements in elasticity, skin thickness, and hue of berries, especially in Merlot when the treatment was applied twice. Conclusions: Inactive yeasts (IYs) showed an effect on the weight of the berries, the anthocyanins, the mechanics, and the color; Merlot significantly improved skin thickness, elasticity, and hue; and Cabernet remained less reactive to treatments. Full article

Anthocyanin-rich purple fruits and vegetables—such as blackcurrants, blueberries, purple sweet potatoes, and red cabbage—are increasingly recognized for their health-promoting properties. These natural pigments exert antioxidant and anti-inflammatory effects, making them relevant to both chronic disease prevention and exercise recovery. This review critically examines current evidence on the redox-modulating mechanisms of anthocyanins, including their interactions with key signaling pathways such as Nrf2 and NF-κB, and their effects on oxidative stress, mitochondrial function, vascular homeostasis, and post-exercise adaptation. Particular attention is given to their bioavailability and the challenges associated with their chemical stability, metabolism, and food matrix interactions. In light of these factors, dietary strategies and technological innovations to improve anthocyanin absorption are also discussed. The synthesis of preclinical and clinical findings supports the potential of anthocyanin-rich foods as functional components in health optimization, athletic performance, and recovery strategies. Full article

This study aimed to evaluate the impregnation process of apple slices with bioactive compounds (BCs) that were obtained from the richest antioxidant fruit powder extracts. Acaí, beetroot, blueberry, cranberry, dragon fruit, and pomegranate powders were assessed on their main BCs, antioxidant capacity (AC), and reducing power (RP) before and after heat treatment to select the extract with the highest and most stable BCs and AC. The effect of pH (3–7) and the total soluble solids (TSSs) (5–15%) on the BCs and AC of selected fruit powder extracts were also evaluated to decide which one should be used to impregnate apple slices. Results indicate that the pomegranate extract presented the highest BCs, AC, and RP among the fruit powders tested, even after heat treatment. Moreover, the TSSs did not affect the BCs from the pomegranate extract; however, pH affected the stability, showing higher values of BCs as the pH was reduced. Apple slices impregnated with pomegranate extract (pH 2) showed an increase in their total phenolic compounds, total anthocyanins, AC, and RP at 25.94, 3085.00, 19.80, and 56.94%, respectively, compared to control apple slices. This study indicates that reducing the pH of pomegranate extracts may increase their antioxidant compounds, showing a higher impregnation of them on apple slices. Full article

Microbeads of raspberry extract were produced using encapsulation matrices alginate + pea protein isolate + psyllium mucilage, alginate + pea protein isolate + psyllium mucilage + okra, and alginate + pea protein isolate + psyllium mucilage + Aloe ferox gel + gallic acid using freeze-drying method. The microbeads were characterised and assessed for their effectiveness on the release, bioaccessibility, of anthocyanin components and antioxidant activities during in vitro digestion. Alginate + pea protein isolate + psyllium mucilage + Aloe ferox gel + gallic acid matrix showed the highest encapsulation efficiency of 91.60% while the lowest encapsulation efficiency was observed in alginate + pea protein isolate + psyllium mucilage + okra (69.94%). Scanning electron microscope images revealed spherical shapes and varying surface morphologies for different encapsulation matrices. Despite the differences observed in Fourier transform infrared spectra, microbeads showed similar thermal degradation patterns. X-ray diffractograms showed amorphous structures for different encapsulation matrices. Comparatively, alginate+ pea protein isolate + psyllium mucilage + Aloe ferox gel + gallic acid microbeads exhibited the highest bioaccessibility for total phenols (93.14%), cyanidin-3-O-sophoroside (54.61%), and cyanidin-3-O-glucoside (55.30%). The encapsulation matrices of different biopolymer combinations (alginate+ pea protein isolate+ psyllium mucilage, alginate + pea protein isolate + psyllium mucilage + okra, and alginate + pea protein isolate + psyllium mucilage + Aloe ferox gel + gallic acid) enhanced anthocyanin stability and protected it against in vitro degradation of bioactive compounds. Full article

The oxidative degradation of anthocyanins in red wine was investigated under controlled conditions using hydroxyl radicals generated in the presence of Cu (II) as a catalyst. A full factorial experimental design with 23 replicates was used to evaluate the effects of hydrogen peroxide concentration, catalyst dosage, and reaction temperature on anthocyanin degradation over a fixed time. Statistical analysis (ANOVA and multiple regression) showed that all three variables and the main interactions significantly affected anthocyanin loss, with temperature identified as the most influential factor. The combined effects were described by a first-order polynomial model. The activation energies for degradation ranged from 56.62 kJ/mol (cyanidin-3-O-glucoside) to 40.58 kJ/mol (peonidin-3-O-glucoside acetate). Increasing the temperature from 30 °C to 40 °C accelerated the degradation kinetics, almost doubled the rate constants and shortened the half-life of the pigments. At 40 °C, the half-lives ranged from 62.3 min to 154.0 min, depending on the anthocyanin structure. These results contribute to a deeper understanding of the stability of anthocyanins in red wine under oxidative stress and provide insights into the chemical behavior of derived pigments. The results are of practical importance for both oenology and viticulture and support efforts to improve the color stability of wine and extend the shelf life of grape-based products. Full article

Central nervous system diseases are highly complex in terms of etiology and pathogenesis, making their treatment and interventions for them a major focus and challenge in neuroscience research. Anthocyanins, natural water-soluble pigments widely present in plants, belong to the class of flavonoid compounds. As natural antioxidants, anthocyanins have attracted extensive attention due to their significant functions in scavenging free radicals, antioxidation, anti-inflammation, and anti-apoptosis. The application of anthocyanins in the field of central nervous system injury, particularly in neurodegenerative diseases, neurotoxicity induced by chemical drugs, stress-related nerve damage, and cerebrovascular diseases, has achieved remarkable research outcomes. However, anthocyanins often exhibit low chemical stability, a short half-life, and relatively low bioavailability, which limit their clinical application. Recent studies have found that the stability and bioavailability of anthocyanins can be significantly improved through nanoencapsulation, acylation, and copigmentation, as well as the preparation of nanogels, nanoemulsions, and liposomes. These advancements offer the potential for the development of anthocyanins as a new type of neuroprotective agent. Future research will focus on the innovative design of nano-delivery systems and structural modification based on artificial intelligence. Such research is expected to break through the bottleneck of anthocyanin application and enable it to become a core component of next-generation intelligent neuroprotective agents. Full article

Anthocyanins (ACNs), characterized by their polyhydroxy structures, exhibit high susceptibility to external environmental factors, which significantly limits their application in the food and industrial sectors. To enhance the stability of anthocyanins, anthocyanin nanoliposomes (ACN-NLs) were developed, with encapsulation efficiency, particle size and zeta potential serving as key evaluation parameters. Furthermore, through layer-by-layer self-assembly and electrostatic interactions, ACN-NLs were modified using synanthrin (SY) and pea protein isolate (PPI). Consequently, PPI-modified ACN-NLs (PPI-ACN-NLs) and SY-PPI-modified ACN-NLs (SY-PPI-ACN-NLs) were successfully synthesized. In this study, the structural characteristics of liposomes were investigated using X-ray diffraction (XRD), their in vitro digestibility was evaluated, and their stability under different temperatures, light conditions, and simulated food system conditions was assessed. The results demonstrated that when the mass ratio of soybean lecithin to cholesterol, soybean lecithin to anhydrous ethanol, and drug-to-lipid ratio were set at 5:1, 3:100, and 3:10, respectively, with an ACN concentration of 4 mg/mL, a pea protein solution with pH 3.0, a PPI concentration of 10 mg/mL, and an SY concentration of 8 mg/mL, the prepared ACN-NLs, PPI-ACN-NLs, and SY-PPI-ACN-NLs exhibited optimal performance. Their respective encapsulation efficiencies were 52.59 ± 0.24%, 83.80 ± 0.43%, and 90.38 ± 0.24%; average particle sizes were 134.60 ± 0.76 nm, 213.20 ± 0.41 nm, and 246.60 ± 0.24 nm zeta potentials were −32.4 ± 0.75 mV, −27.46 ± 0.69 mV, and −16.93 ± 0.31 mV. The changes in peak shape observed via X-ray diffraction (XRD), in vitro digestion profiles, and alterations in anthocyanin release rates under different conditions collectively indicated that the modification of ACN-NLs using SY and PPI enhanced the protective effect on the ACNs, improving their biological activity, and providing a robust foundation for the practical application of ACNs. Full article

Color, aroma, and overall sensory quality in red wines are largely influenced by oxygen availability during fermentation. This study evaluated the effects of micro-oxygenation under hyperbaric conditions on the physicochemical, chromatic, volatile, and sensory properties of Vitis vinifera L. cv. Monastrell grape must. Grape clusters were manually harvested and fermented under controlled conditions, applying micro-oxygenation treatments at two fermentation stages (day 3 and day 13) within a hyperbaric chamber. Physicochemical analyses, CIELab color measurements, visible reflectance spectra, GC-FID volatile profiling, and descriptive sensory analysis were performed. Micro-oxygenated samples (M1_MOX and M2_MOX) showed significant increases in lightness (L*), redness (a*), chroma (C*), and reflectance in the 520–620 nm range, indicating enhanced extraction and stabilization of phenolic pigments. Volatile analysis revealed that these samples also contained higher concentrations of key esters and terpenes associated with fruity and floral notes. Sensory evaluation confirmed these findings, with MOX-treated wines displaying greater aromatic intensity, flavor persistence, and varietal character. Control samples (M1_CON and M2_CON) exhibited lower color saturation and volatile compound content, along with diminished sensory quality. These results suggest that hyperbaric micro-oxygenation is an effective strategy for improving color intensity and aromatic complexity during red wine fermentation under controlled, non-thermal conditions. Full article

Whole mulberry juice (WMBJ) was prepared using a novel high-energy fluidic microfluidizer (HEFM). The effects of varying treatment pressures (0–120 MPa) on the physical stability and nutritional quality of the juice were investigated. As the pressure increased, the average particle size (D[4,3]) decreased from 232.46 μm to 38.27 μm. This indicated that the pulp particles became smaller and more evenly dispersed, resulting in an increase in the apparent viscosity. At 90 MPa, the precipitation weight ratio increases, the turbidity value is the lowest, and the physical stability is significantly improved. Furthermore, the HEFM treatment exhibited a favorable impact on the soluble solids, pH value, total acid content, color, and antioxidant activity of the WMBJ. The contents of anthocyanins, ascorbic acid, and total polyphenols in the WMBJ reached their zenith with the 90 MPa treatment. The results demonstrated that WMBJ, characterized by its excellent physical stability and high nutritional value, can be effectively prepared through the utilization of HEFM technology. This technological approach represents a novel method for industrial WMBJ production that is both efficient and environmentally friendly while ensuring the preservation of the product’s quality. Full article

The structure of anthocyanins in mulberry wine is highly unstable and, therefore, degrades during the fermentation and aging process. This instability hinders the maintenance of color, affects the sensory quality, and impedes the development of the mulberry wine industry. In this study, high-yielding acetaldehyde yeasts Saccharomyces cerevisiae GS32 and Candida glabrata GS13, as well as high-yielding pyruvate yeast Candida xestobii D1, were selected from our laboratory’s strain bank for application in mulberry wine fermentation. The objective was to determine the impact of these high-yielding yeasts on improving anthocyanin content and color stability. The results revealed that different strains and inoculation methods significantly influenced anthocyanin content and color stability in mulberry wine. The GS32 exhibited the highest increase in total anthocyanin content, while the D1 showed a superior retention rate for C3G (a specific type of anthocyanin). Over a period of 1–5 weeks of aging time, minimal changes in color were observed across all treatment groups. These findings suggest that fermenting with yeast strains that yield high levels of pyruvate and acetaldehyde is an effective approach to address issues related to the poor stability of anthocyanins in mulberry wine. Full article

Lactobacillus plantarum exhibits probiotic effects, including regulating the balance of the intestinal microbiota and enhancing immune function. However, this strain often experiences viability loss upon ingestion due to harsh conditions within the human digestive tract. This study aimed to evaluate the efficacy of metal–phenol networks (MPNs) fabricated via three polyphenols—tannic acid (TA), tea polyphenol (TP), and anthocyanin (ACN)—combined with Fe(III) coatings in protecting Lactobacillus plantarum during simulated digestion and storage. The results demonstrated that MPNs formed a protective film on the bacterial surface. While TA and ACN inhibited the growth of Lactobacillus plantarum YJ7, TP stimulated proliferation. Within the MPNs system, only Fe(III)-TA exhibited growth-inhibitory effects. Notably, ACN displayed the highest proliferation rate during the initial 2 h, followed by TP between 3 and 4 h. All MPN-coated groups maintained high bacterial viability at 25 °C and −20 °C, with TP-coated bacteria showing the highest viable cell count, followed by TA and ACN. In vitro digestion experiments further revealed that the Fe(III)-ACN group exhibited the strongest resistance to artificial gastric juice. In conclusion, tea polyphenol and anthocyanin demonstrate superior potential for probiotic encapsulation, offering both protective stability during digestion and enhanced viability under storage conditions. Full article

Public concerns about the health risks of synthetic antioxidants have prompted the meat industry to look for natural alternatives rich in phenols with strong antioxidant properties. This study investigates the use of blackcurrant (BCP), lingonberry (LP), and sour cherry (SCP) powders as natural substitutes for synthetic nitrites in reformulating two clean-label salami types, smoked and cooked and smoked and scalded, with a focus on their effects on oxidative stability during processing and refrigerated storage (4 °C). Nitrite-free formulations were prepared with each fruit powder at three inclusion levels to provide total phenolic contents of 90, 200, and 300 mg gallic acid equivalents (GAE)/kg of processed meat. A nitrite-containing control (90 mg/kg) and an additive-free control were included for comparison. The phytochemical profiles of powders were characterized by total phenolic, flavonoid, monomeric anthocyanin contents, and L-ascorbic acid levels. Antioxidant activity was assessed via 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and ferric reducing antioxidant power (FRAP) assays. Salami samples were analyzed for proximate composition, and lipid oxidation was monitored at 0, 15, and 30 days of storage using peroxide value, inhibition of oxidation, p-anisidine value, TOTOX, and thiobarbituric acid value. Fruit powders demonstrated dose- and type-dependent inhibition of primary and secondary lipid oxidation, enhancing oxidative stability during processing and storage. After 30 days of storage, oxidation markers in fruit-enriched salami remained below recommended thresholds, confirming effective control of lipid oxidation. The inhibitory potential followed the order BCP > LP > SCP, consistent with antioxidant profiles as reflected by DPPH and FRAP values. BCP at 300 mg GAE/kg showed a stronger lipid oxidation inhibition than sodium nitrite. Promising improvements in lipid oxidation resistance were also observed with LP at 300 mg GAE/kg and BCP at 200 mg GAE/kg. These findings highlight the potential of fruit-derived antioxidants to support the development of more sustainable, value-added meat products without compromising quality. Full article

Polyphenols are known as secondary metabolites, which are crucial bioactive compounds that play a significant role in enhancing human health. Chromatographic methods are typically used to identify polyphenols after food extraction. The extraction methods are fundamental, however, they are implemented with some differences, including extractant type, according to the food. Polyphenols are mostly found in some foods, including grapes, olives, cherries, and apples. Foods have diverse polyphenols, which differ according to the food type. Moreover, they have flavonols, flavanols, flavones, flavanones, isoflavones, and anthocyanins as various subgroups of polyphenols, which can change in terms of quantity and quality along with several factors, including the type, growing region, germination time, and harvest season of the food. The consumption of polyphenols is crucial for human health due to their anti-cancer, anti-tumor, anti-inflammatory, cardiometabolic risk management, antimicrobial, immunomodulatory, and antioxidant effects. In the valorization of polyphenols, the consumption dose is also important to effectively benefit from the polyphenols of plant-based foods. Several in vitro and in vivo studies have tested the polyphenols’ digestion ability and preservation ability in gut microbiota and their effect on the microbiota to determine the benefits and effects of polyphenols in several areas. According to these studies, polyphenols can be used to fight against disease. In addition, diverse applications, including encapsulation and polyphenol coating, are used to stabilize, preserve, and improve the bioaccessibility of polyphenols. Even though polyphenol-rich foods are consumed for nutrition in daily life, they are also used as nutritional ingredients in the food industry to produce functional foods, and functional foods are enriched with food by-products to enhance their nutritional value, especially in terms of polyphenols. Particularly, food by-products are used to enrich functional foods, which are preferred in healthy life diets due to the diversity and amount of bioactive ingredients, including the polyphenol types of the food by-products. Furthermore, polyphenols also provide the preservation ability of storage and improve the bioaccessibility of bioactive ingredients during the digestion of functional foods. This review article examines the polyphenol ingredients of several types of food used in the food industry. It explains the effective factors that affect the amount and type of food and determines the impact of polyphenols on polyphenol-enriched products and functional foods. The article also provides a brief exemplification of the value of polyphenol-rich food by-products in the context of functional food production. Several studies presented in this review article demonstrate the value of polyphenols, particularly in the food industry and functional food production. Full article

The browning of fruit juices and nectars is a common issue in the beverage industry and is a particular problem in strawberry nectars, where it significantly reduces the shelf-life. Polyphenol oxidases (PPOs), which are multicopper enzymes responsible for the oxidation of a wide plethora of polyphenols in plants, have been widely assumed to be involved in the enzymatic browning of strawberry nectar. To investigate the possible involvement of PPOs, the substrate specificity of four recombinant PPOs and their gene expression pattern in 10 cultivars of Fragaria × ananassa at five ripening stages were determined. This allowed us to obtain adequate amounts of enzymes to study them independently and without interfering matrix effects. All four PPOs possess monophenolase activity, which was particularly high for PPO4. PPO3 did not show sufficient stability for the kinetic studies. The other three showed a high preference for the flavan 3-ol catechin with a 2-fold higher catalytic efficiency compared to dopamine for PPO1 and PPO2. At a neutral pH, they also showed activity with cyanidin but not with pelargonidin, which is the prevalent anthocyanidin type in strawberry. The enzymes showed a high affinity but only low turnover rates for the dihydrochalcone phloretin, resulting in an inhibitory effect that was strong enough to extend the shelf-life of the strawberry nectar by one week if phloretin was added in high concentrations (600 µM). PPO1 and PPO2 were prevalently expressed in all fruit stages. The gene expression of the four PPOs did not correlate with the color stability of the nectars of the 10 varieties and also showed a random expression pattern during fruit development. The limited activity in acidic conditions and the low substrate specificity for pelargonidin does not point to a crucial role for PPOs in the browning of strawberry nectar, but the high catalytic efficiency with catechin as a substrate could contribute to anthocyanin degradation via mechanisms such as copolymerization. Full article

Lactic acid fermentation has emerged as a promising strategy to enhance the functional and health-promoting qualities of plant-based foods. This study evaluates the impact of lactic acid fermentation on the antioxidant capacity, microbial viability, and chemical stability of freeze-dried peaches, aiming to develop a functional food with probiotic potential. Two bacterial strains—Fructilactobacillus fructivorans (P_FF) and Lactiplantibacillus plantarum (P_LP)—were used to assess strain-dependent effects on microbial and bioactive compound profiles. Microbiological analyses included total viable count (TVC), fungal count (TFC), and total lactic acid bacteria (TCLAB). Chemical analyses comprised polyphenol, flavonoid, anthocyanin, carotenoid, sugar, and vitamin C content, as well as antioxidant activity (DPPH, ABTS, reducing power). Thermal and structural stability were examined via thermogravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FTIR). Fermentation significantly increased the counts of lactic acid bacteria, achieving 8.38 and 7.86 log CFU/g after freeze-drying, respectively. While total polyphenols slightly decreased (by 9.5% and 1.1% for L. plantarum and F. fructivorans, respectively), flavonoid content increased notably by 16.1% in F. fructivorans-fermented samples. Antioxidant activities, assessed by ABTS and DPPH assays, were largely maintained, although a reduction in reducing power was observed. Additionally, fermentation led to sucrose hydrolysis, resulting in higher glucose and fructose contents, and increased water content in the final products. Minor increases in total fungal counts were noted after freeze-drying but remained within acceptable limits. Overall, the combination of fermentation and freeze-drying processes preserved key antioxidant properties, enhanced microbial safety, and produced functional peach-based products with improved bioactivity and extended shelf life. These findings highlight the potential of fermented freeze-dried peaches as innovative, health-oriented alternatives to traditional fruit snacks. Full article