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Betel leaves have deep roots in India's cultural heritage and have long been known for their use in traditional diets as a masticatory agent. These leaves contain beneficial compounds like antimicrobials, antioxidants, and anticancer properties. This study aims to investigate how betel leaf essential oil (BLEO) can act as a preservative for orange, grape, watermelon, and sugarcane juices. To make sure BLEO doesn't affect the taste, a sensory study was done using fuzzy logic analysis to determine the right concentration. Physicochemical and microbial properties in control and BLEO-treated juices were evaluated at weeks 0 and 2. Results showed that the addition of BLEO in fruit juices yielded a significant reduction in microbial populations, in total plate count and yeast and mold count. The decrease in free radical scavenging activity observed in BLEO-treated juices was comparatively less pronounced than in the control. GC-MS analysis has identified the bioactive compounds present in BLEO, revealing high concentrations of bioactive compounds. The observation of the study demonstrates the remarkable potential of BLEO to serve as a natural preservative in a diverse range of fruit juices. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05963-9.

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This study aimed to assess the impact of adaptation of ten strains of O157:H7 and non-O157 Escherichia coli to low pH (acid shock or slow acidification) and the effects of this exposure or not on the resistance of E. coli strains to UV radiation in orange juice (pH 3.5). The acid-shocked cells were obtained through culture in tryptic soy broth (TSB) with a final pH of 4.8, which was adjusted by hydrochloric, lactic, or citric acid and subsequently inoculated in orange juice at 4 °C for 30 days. No significant differences (p > 0.05) in survival in orange juice were observed between the serotypes O157:H7 and non-O157:H7 for acid-shocked experiments. After slow acidification, where the cells were cultured in TSB supplemented with glucose 1% (TSB + G), a significant increase (p < 0.05) in survival was observed for all strains evaluated. The D-values (radiation dose (J/cm2) necessary to decrease the microbial population by 90%) were determined as the inverse of the slopes of the regressions (k) obtained by plotting log (N/N0). The results show that among the strains tested, E. coli O157:H7 (303/00) and O26:H11 were the most resistant and sensitive strains, respectively. According to our results, the method of acid adaptation contributes to increasing the UV resistance for most of the strains tested.

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Fermented milk beverages have been known for years and are characterized by excellent health-promoting properties. Therefore, consumer attention has been drawn to this product type in recent years. In the presented research, the technology of production in laboratory and industrial scale of controlled fermentation of whey beverages containing sweet and sour organic cow's or goat's whey with the addition of organic fruit juices (apple, blackcurrant juice or Kamchatka berry), has been described. Food production on a laboratory scale involves small batch processes designed for experimentation and refinement, often with precise control over variables and conditions. In contrast, industrial-scale food production in enterprises focuses on large volume output with an emphasis on efficiency, consistency, and adherence to regulatory standards for mass consumption. In this study was examined the amino acid content and nutritional value of the obtained products. Tests were carried out on fermented whey drinks' microbiology and antioxidant properties. The significance was determined using an ANOVA (ANOVA)-each prepared drink was characterized by better antioxidant properties and nutritional values compared with product without juice addition. Microbiological examination proved that only one product was not fit for consumption according to the Polish norm. Using whey (goat and cow) as a base for a fermented beverage with enhanced health benefits is a positive step toward using products commonly regarded as waste.

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BACKGROUND: Red fruits are characterised by a particularly high content of bioactive compounds, e.g. anthocyanins, tannins, pectins, vitamins and minerals. Dietary supply of proper amounts of antioxidants is essential to reduce oxidative stress, and thus is an important element in the prevention of lifestyle diseases. OBJECTIVE: The aim of the study was to evaluate and compare the content of polyphenols in selected red fruit juices (chokeberry, elderberry, pomegranate, cranberry), as well as to assess the impact of storage time on the content of these compounds in the analysed samples. MATERIAL AND METHODS: The research material consisted of 17 juices (100%): 3 chokeberry juices, 4 elderberry juices, 5 pomegranate juices and 5 cranberry juices, which differed in terms of the manufacturer, type, price range, country of origin and production method. The total polyphenol content was measured by spectrophotometry using the Folin�Ciocalteu reagent. The procedure was based on a modified method described by Waterhouse. Active acidity (pH) was measured with the potentiometric method using a pH-meter and the sucrose content was measured using a refractometer. RESULTS: The highest mean content of polyphenolic compounds was found in chokeberry and elderberry juices. Juice storage time did not reduce the mean content of polyphenolic compounds. The highest sucrose content was found in chokeberry juices and the lowest in cranberry juice. CONCLUSIONS: Chokeberry and elderberry juices had the highest content of polyphenols among the tested products. Juices stored after opening in accordance with the manufacturer's instructions (at 4°C) do not lose their nutritional properties.

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Lactic acid bacteria (LAB) are widely applied for fermentation purposes in dairy and non-dairy food matrices with beneficial technological and health-promoting properties. This study describes the effect of two lactic acid bacteria, namely, Lactiplantibacillus paracasei SP5 and Pediococcus pentosaceus SP2, on the phenolic profiles, antioxidant activities, total phenolic content (TPC), carotenoid content, and sensorial profile of two different mixed fruit juices. After 48 h of fermentation, both LABs retained viability over 9 Log CFU/mL in both juices. The TPC, zeaxanthin + lutein, ß-carotene content, and antioxidant activity (AA) were elevated for both LABs and mixed juices after 48 h of fermentation compared to control samples. Regarding the phenolic profile, both juices exhibited a significant decrease in chlorogenic acid levels, while quinic acid and tyrosol concentrations showed notable increases.

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The experiments reported in this research paper aimed to evaluate the physico-chemical and sensory characteristics, microbial quality and antioxidant potential of goat's milk paneer during storage (0-12 d, 4 ± 1°C). The juices from five different citrus fruits were used as coagulant (treatments) to make goat's milk paneer. The pH of all paneer samples decreased during storage whereas titratable acidity increased. Ash (%) fat (%) and protein (%) of paneer increased slightly during storage, whereas sensory perception decreased. The juices from all the citrus fruit varieties showed high contents of total phenolics and total flavonoids which ultimately influenced ferric reducing antioxidant power, total antioxidant capacity and radical scavenging activities. As the contents of different juices were also retained in the paneer matrix, so paneer coagulated with citrus juices also showed encouraging results in terms of total phenolic and flavonoid contents, ferric reducing antioxidant power and radical scavenging activities. Amongst all the paneers, the most promising was that coagulated by kinnow juice. In addition, the whey obtained from paneer coagulated by citrus juices also showed appreciable quantities of total phenolic and flavonoid contents, thereby beneficially influencing ferric reducing antioxidant power andradical scavenging activities. It is concluded that citrus juices improve the sensorial quality and antioxidant potential of goat's milk paneer and its whey.

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In this study, compact 3D-printed carbon black (CB) electrodes were manufactured for using in folic acid (FA) analysis in fruit samples. Before application in FA analysis, the electrode surfaces were characterized by high-resolution scanning electron microscopy and voltammetry using well-known redox probes. Square wave voltammetric study presented linear responses in the range between 10 and 200 µmol/L (R2 > 0.99), exhibited a suitable detection limit (LOD) of âˆ¼ 5.1 µmol/L and acceptable performance in terms of reproducibility and anti-interference experiments. The analysis of FA in four different food samples using the proposed method agreed statistically with a comparative technique based on spectrophotometric measurements. Moreover, results from photostability experiments indicated that FA can be degraded after 5 and 20 min of UV exposure. These results successfully demonstrated the analytical feasibility of the 3D-printed electrodes as sensing material and for monitoring the photostability of FA in different fruit matrices.

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Exposure to heavy metals can endanger the health of exposed people in the long term. The consumption of fruit juice is increasing; it is important to estimate the health risk of consumers due to heavy metals. The current study was carried out for the analysis of toxic metals (lead (Pb), arsenic (As), and cadmium (Cd)) and essential elements (copper (Cu) and zinc (Zn)) in 60 samples of traditional and industrial fruit juices (10 samples of different brands of apple, orange, grape, peach, mango, and pineapple) in Hamadan, West Iran, using inductivity coupled plasma optical emission spectrometry (ICP-OES) method. The validation protocol included precision of the analytical method; recovery, the determination of the limit of detection (LOD), the limit of quantification (LOQ), and linearity were measured. Moreover, risk assessment was detected using target hazard quotient (THQ) and cancer risk (CR) by the Monte Carlo simulation (MCS) model. The ranking of metal concentration in traditional and industrial fruit juices was Zn > Cu > As > Pb > Cd. In all samples, concentrations of heavy metals in industrial fruit juices were higher than traditional fruit juices p < < 0.001. The level of metals in all samples was lower of the US Environmental Protection Agency (USEPA), the World Health Organization (WHO), and the Iran Standard (IS) permissible limit set for drinking water. In terms of non-carcinogenic, values of toxic elements for children and adult in traditional and industrial fruit juices were 1.6E-3 and 1.72E-3 and 2.6E-3 and 1.85E-3, respectively. The 95th percentile of CR in adults and children due to both industrial and traditional fruits juices was higher than 1E-6; hence, reducing the concentration of As in fruit juices should be conducted. Consumption of fruit juice can increase carcinogenic risk of consumers. Therefore, it is recommended to consume it with caution.

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The beneficial health effects of prebiotics have been demonstrated in numerous research papers. However, their incorporation into daily food remains unfamiliar to consumers. This work evaluates the effects of the addition of resistant maltodextrin (RMD) on the sensory attributes of pasteurised orange juice, together with the physico-chemical properties and the aromatic profile. RMD addition increased the sweetness and decreased the acidity and bitterness, resulting in a higher overall panellists' rating of orange juice. It also proportionally increased °Brix together with density and decreased acidity. Colour changes were registered with higher RMD concentrations. Orange pulp presence affected the volume particle size distribution analysis, while RMD addition did not have any effect. The aroma volatile compounds were also analysed. Pulp-added samples showed a higher quantity of alcohol and aldehydes, whereas pulp-free samples registered higher terpene and terpenoid values. Ketones and acids were also quantified. RMD had a moderate impact on volatile compound quantifications, with the orange pulp presence playing a much more decisive role. A correspondence analysis was also performed to relate instrumental and sensory determinations for all samples. This work proves that the addition of RMD to orange juice is technologically feasible while also achieving a good response at the sensory level.

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Background: Dental erosion is the loss of dental hard tissues through the acid dissolution of tooth minerals. One of the major factors that cause erosion is the consumption of acidic food and drinks. This study investigated and compared the effect of vitamin waters, herbal beverages, carbonated soft drinks, and fruit juices on the loss of human dental hard tissue. Methods: Human tooth samples were immersed in various drinks: vitamin waters, herbal beverages, carbonated soft drinks, and fruit juices. The pH value of each drink was measured using a pH meter. The weight of each sample was determined before and after six days of immersion in the tested drink, and the weight loss percentage was calculated. The exposed tooth surfaces were also examined under a scanning electron microscope. Results: Most of the tested drinks were acidic and displayed pH values lower than the critical pH for enamel erosion. Significant weight loss of the tooth samples was found in all tested drink groups. Additionally, the samples immersed in fruit juices and herbal beverages exhibited significantly greater weight loss than those immersed in carbonated soft drinks. Scanning electron micrographs showed samples immersed in the tested drinks to demonstrate structural disintegration with occasional void spaces, except for samples immersed in Doi Kham® Lemongrass drink. Conclusion: Most of the tested drinks have the potential to cause dissolution and destruction of dental hard tissues. Consumers should be aware that prolonged exposure to these drinks could lead to permanent loss of tooth mineral and dental erosion.

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The main objective of the study is the estimation of elemental impurities in selected packaged commercial fruit juices and fresh fruit juices available in Ahmedabad, Gujarat. Estimation of seventeen samples (9 commercial fruit juices and 8 fresh fruit juices) was carried out for elemental impurities which include lead, cadmium, arsenic, mercury, methyl mercury, nickel, chromium, tin, copper, and zinc. Inductively coupled plasma-mass spectroscopy (ICP-MS) with microwave-assisted sample digestion was used to determine the element content of samples. The ICP-MS method was confirmed for accuracy by performing validation with validation parameters such as linearity, precision, and accuracy. The method's trueness was confirmed with single-element standards. The results were compared with Food Safety and Standards Authority of India (FSSAI) standards. Arsenic, mercury, methyl mercury, tin, and copper were within permissible limits in all samples of fruit juices. The concentration of lead was found to exceed limits in 5 samples of commercial fruit juices which were 0.07, 0.13, 0.18, 0.21, and 0.38 mg/kg, respectively. The concentration of nickel was found to be above permissible limits in 5 samples (1.26, 1.72, 1.95, 3.24, and 4.07 mg/kg) of commercial fruit juices and 6 samples of fresh fruit juices (0.19. 0.21, 0.21, 0.42, 0.66, and 2.42 mg/kg). The concentration of chromium was found to be above permissible limits in 5 samples (3.13, 3.51, 4.29, 5.91, and 6.02 mg/kg) of commercial fruit juices and 6 samples of fresh fruit juices (0.80. 0.88, 0.98, 0.99, 1.16, and 8.95 mg/kg). Health risk assessment was performed for elemental impurities. Target hazard quotient and health risk index for elemental impurities were found to be less than 1 which is considered safe for consumers. Hazard index for elemental impurities was found to be more than 1 in two samples which can cause serious non-carcinogenic risk to consumers. Target carcinogenic risk was found within acceptable levels for all elemental impurities in all samples of fruit juices. Essential elements like copper and zinc are required by the human body for various body functions but heavy metals like lead, arsenic, and cadmium are highly toxic to human beings due to their adverse effects and it needs to be controlled. Lead poses a significant health risk to human health. It is essential to further monitor the levels of elemental impurities on a regular basis in commercial and fresh fruit juices.

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Objectives: The aim of this study was to evaluate the effect of fruit juices on Multi-Drug Resistant (MDR) bacterial pathogens involved in Urinary Tract Infections (UTIs) and Sexually Transmitted Infections (STIs) among tribal women in the district Anuppur, Madhya Pradesh, India. Methods: Fresh juices of lemon (Citrus limon), amla/Indian gooseberry (Phyllanthus emblica), pineapple (Ananas comosus), mosambi/sweet lime (Citrus limetta), orange (Citrus sinensis), kiwi (Actinidia deliciosa), and pomegranate (Punica granatum) fruits were evaluated for in vitro antibacterial activity against bacterial pathogens involved in UITs and STIs among tribal women. Physico-chemical analysis of fresh fruits was also carried out by measuring the pH, moisture, protein, fat, crude fibre, carbohydrate, and ascorbic acid content. Results: Lemon and amla juice showed better antibacterial activity against the pathogens as compared to other juices. MIC results fruit juices against UTIs and STIs pathogens vary depending on the specific pathogen and juice chemical constituents. The physico-chemical analysis showed that the moisture content was highest in mosambi (90%), followed by orange (87%). Ascorbic acid content was found highest in amla (540 mg/100 g), followed by kiwi (90.3 mg/100 g). Pomegranate showed highest concentration of carbohydrate (15.28 g/100 g), fat (1.28 g/100 g), and protein (1.65 g/100 g). Lemon juice had lowest pH of 2.20, followed by amla 2.67. Conclusion: The lemon juice showed highest antibacterial activity against MDR bacterial pathogens involved in UTIs and STIs among tribal women in district Anuppur, Madhya Pradesh, India. The low pH of lemon may be responsible for its high antibacterial activity as compared to other juices.

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Fruit juices are one of the most widely consumed beverages worldwide, and their production is subject to strict regulations. Therefore, this study presents a methodology based on the use of headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) in combination with machine-learning algorithms for the characterization juices of different raw material (orange, pineapple, or apple and grape). For this purpose, the ion mobility sum spectrum (IMSS) was used. First, an optimization of the most important conditions in generating the HS was carried out using a Box-Behnken design coupled with a response surface methodology. The following factors were studied: temperature, time, and sample volume. The optimum values were 46.3 °C, 5 min, and 750 µL, respectively. Once the conditions were optimized, 76 samples of the different types of juices were analyzed and the IMSS was combined with different machine-learning algorithms for its characterization. The exploratory analysis by hierarchical cluster analysis (HCA) and principal component analysis (PCA) revealed a clear tendency to group the samples according to the type of fruit juice and, to a lesser extent, the commercial brand. The combination of IMSS with supervised classification techniques reported an excellent result with 100% accuracy on the test set for support vector machines (SVM) and random forest (RF) models regarding the specific fruit used. Nevertheless, all the models have proven to be an effective alternative for characterizing and classifying the different types of juices.

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Drinking wine is a processed beverage that offers high nutritional and health benefits. It is produced from grape must, which undergoes fermentation by yeasts (and sometimes lactic acid bacteria) to create a product that is highly appreciated by consumers worldwide. However, if only one type of yeast, specifically Saccharomyces cerevisiae, was used in the fermentation process, the resulting wine would lack aroma and flavor and may be rejected by consumers. To produce wine with a desirable taste and aroma, non-Saccharomyces yeasts are necessary. These yeasts contribute volatile aromatic compounds that significantly impact the wine's final taste. They promote the release of primary aromatic compounds through a sequential hydrolysis mechanism involving several glycosidases unique to these yeasts. This review will discuss the unique characteristics of these yeasts (Schizosaccharomyces pombe, Pichia kluyveri, Torulaspora delbrueckii, Wickerhamomyces anomalus, Metschnikowia pulcherrima, Hanseniaspora vineae, Lachancea thermotolerans, Candida stellata, and others) and their impact on wine fermentations and co-fermentations. Their existence and the metabolites they produce enhance the complexity of wine flavor, resulting in a more enjoyable drinking experience.

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OBJECTIVE: To validate a culturally tailored 7-day beverage intake questionnaire for Latino children (BIQ-L). DESIGN: Cross-sectional. SETTING: Federally qualified health center in San Francisco, CA. PARTICIPANTS: Latino parents and their children aged 1-5 years (n = 105). VARIABLES MEASURED: Parents completed the BIQ-L for each child and three 24-hour dietary recalls. Participants' height and weight were measured. ANALYSIS: Correlations between the mean intake of beverages in 4 categories as determined by the BIQ-L and three 24-hour dietary recalls were assessed. Multivariable linear regression examined the association between sugar-sweetened beverages (SSB) servings as determined by the BIQ-L and child body mass index z-score. RESULTS: Mean daily intake of SSB (r = 0.52, P < 0.001), 100% fruit juice (r = 0.45, P < 0.001), flavored milk (r = 0.7, P < 0.001), and unflavored milk (r = 0.7, P < 0.001) from the BIQ-L were correlated with intake assessed via three 24-hour dietary recalls. In the multivariable model, weekly servings of SSBs were associated with child body mass index z-score (ß = 0.15, P = 0.02). Culturally specific beverages comprised 38% of the SSB intake reported on the BIQ-L. CONCLUSIONS AND IMPLICATIONS: The BIQ-L is a valid tool for assessing beverage intake among Latino children aged 1-5 years. The inclusion of culturally specific beverages is critical for accurately assessing beverage intake among Latino children.

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AIMS: Recent studies have demonstrated the associations of the consumption of different beverages with cardiometabolic diseases, whereas no studies have investigated such associations in heart failure (HF). Thus, this study aimed to explore the associations of the consumption of sugar-sweetened beverages (SSBs), artificially sweetened beverages (ASBs), and pure fruit/vegetable juices (PJs) with the risk of incident HF. METHODS AND RESULTS: This prospective cohort study included 209 829 participants in the UK Biobank who completed at least one 24-h diet questionnaire and who were free of baseline HF. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs). During a median follow-up of 9.9 years, 4328 incident HF cases were recorded. Compared to corresponding non-consumers, individuals who consumed >2 L/week SSBs or ASBs had an increased risk of HF (HR: 1.22, 95% CI: 1.08-1.38 and HR: 1.30, 95% CI: 1.16-1.47, respectively) in the multivariate adjusted model. An inverse association was observed between the consumption of >0-1 L/week PJs and the risk of HF (HR, 0.90; 95% CI, 0.83-0.98). Additionally, a significant interaction was observed between PJ consumption and sleep duration on HF risk (P for interaction = 0.030). CONCLUSIONS: Increased consumption of SSBs or ASBs may be an independent risk factor for HF, whereas moderate intake of PJs may have a protective effect on HF.

High intake of sugar-sweetened or artificially sweetened beverages was associated with an increased risk of heart failure, and moderate intake of pure fruit/vegetable juices was inversely associated with incident heart failure. Consumption of artificially sweetened beverages is a risk factor for heart failure; thus, it may not be a safe alternative to sugar. Moderate consumption of pure fruit/vegetable juices may be a preventive strategy for heart failure.

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BACKGROUND: Studies of the associations between soft drinks and the risk of cancer showed inconsistent results. No previous published systematic reviews and meta-analysis has investigated a dose-response association between exposure dose and cancer risk or assessed the certainty of currently available evidence. Therefore, we aim to demonstrate the associations and assessed the certainty of the evidence to show our confidence in the associations. METHODS: We searched Embase, PubMed, Web of Science, and the Cochrane Library from inception to Jun 2022, to include relevant prospective cohort studies. We used a restricted cubic spline model to conduct a dose-response meta-analysis and calculated the absolute effect estimates to present the results. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess the certainty of the evidence. RESULTS: Forty-two articles including on 37 cohorts enrolled 4,518,547 participants were included. With low certainty evidence, increased consumption of sugar-sweetened beverages (SSBs) per 250 mL/day was significantly associated with a 17% greater risk of breast cancer, a 10% greater risk of colorectal cancer, a 30% greater risk of biliary tract cancer, and a 10% greater risk of prostate cancer; increased consumption of artificially sweetened beverages (ASBs)re per 250 mL/day was significantly associated with a 16% greater risk of leukemia; increased consumption of 100% fruit juice per 250 mL/day was significantly associated with a 31% greater risk of overall cancer, 22% greater risk of melanoma, 2% greater risk of squamous cell carcinoma, and 29% greater risk of thyroid cancer. The associations with other specific cancer were no significant. We found linear dose-response associations between consumption of SSBs and the risk of breast and kidney cancer, and between consumption of ASBs and 100% fruit juices and the risk of pancreatic cancer. CONCLUSIONS: An increment in consumption of SSBs of 250 mL/day was positively associated with increased risk of breast, colorectal, and biliary tract cancer. Fruit juices consumption was also positively associated with the risk of overall cancer, thyroid cancer, and melanoma. The magnitude of absolute effects, however, was small and mainly based on low or very low certainty of evidence. The association of ASBs consumption with specific cancer risk was uncertain. TRIAL REGISTRATION: PROSPERO: CRD42020152223.

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Since certain constituents are not naturally present in pure fruit juices, incorporating herbal extracts can provide specific sensory properties to the beverages and improve their biopotential. In our previous research, it was found that sage (Salvia officinalis L.), wild thyme (Thymus serpyllum L.), and combinations of their extracts had the highest total phenolic content and a unique composition of volatile compounds, which can contribute to the aromatic and antioxidant qualities of functional products. Therefore, this research aimed to investigate the potential of sage and wild thyme extracts, as well as their mixture (wild thyme:sage at 3:1, v/v), to enrich fruit juices (apple, pineapple, and orange). Obtained beverages were evaluated for sensory properties as well as phenolic and headspace composition (UPLC-MS/MS and HS-SPME/GC-MS analysis) and antioxidant capacity (ORAC assay). The incorporation of wild thyme extract in pineapple juice provided the most harmonious flavor and the highest content of volatile compounds (on PDMS/DVB fiber). The orange juice formulations were the most enriched with phenolic and volatile compounds (on DVB/CAR/PDMS fibers). The highest antioxidant capacity was observed in the formulation with orange juice and sage extract (22,925.39 ± 358.43 µM TE). This study demonstrated that enriching fruit juices with sage and wild thyme extracts could create functional beverages with improved sensory and health-promoting properties, providing valuable insights for the food and beverage industry to meet the growing demand of health-conscious consumers for natural and functional products.

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Osmotic distillation (OD) was implemented at laboratory scale to concentrate a red fruit juice produced from a blend of blood orange, prickly pear, and pomegranate juice. The raw juice was clarified by microfiltration and then concentrated by using an OD plant equipped with a hollow fiber membrane contactor. The clarified juice was recirculated on the shell side of the membrane module, while calcium chloride dehydrate solutions, used as extraction brine, were recirculated on the lumen side in a counter-current mode. The influence of different process parameters, such as brine concentration (20, 40, and 60% w/w), juice flow rate (0.3, 2.0, and 3.7 L min-1), and brine flow rate (0.3, 2.0, and 3.7 L min-1) on the performance of the OD process in terms of evaporation flux and increase in juice concentration, was investigated according to the response surface methodology (RSM). From the regression analysis, the evaporation flux and juice concentration rate were expressed with quadratic equations of juice and brine flow rates, as well as the brine concentration. The desirability function approach was applied to analyse the regression model equations in order to maximize the evaporation flux and juice concentration rate. The optimal operating conditions were found to be 3.32 L min-1 brine flow rate, 3.32 L min-1 juice flow rate, and an initial brine concentration of 60% w/w. Under these conditions, the average evaporation flux and the increase in the soluble solid content of the juice resulted in 0.41 kg m-2 h-1 and 12.0 °Brix, respectively. Experimental data on evaporation flux and juice concentration, obtained in optimized operating conditions, resulted in good agreement with the predicted values of the regression model.

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Microfiltration of citrus fruit juices using membrane technology is a promising method for clarification without losing their inherent properties to extend their shelf life. The present work discusses the development of a tubular ceramic microfiltration membrane and its performance in clarifying two kinds of citrus fruit juices, mandarin and sweet orange. The membrane was prepared by the extrusion method from indigenous bentonite clay, exhibited a porosity of 37% with 0.11 µm pore size, and possessed adequate flexural strength of 18 MPa. The fabricated membrane's potential was evaluated by conducting the tangential filtration of both centrifuged and enzyme-treated centrifuged fruit juices. Also, the applied pressure (68.94-344.7 kPa) and crossflow rate (110-150 Lph) were varied to study the clarified juice properties. At low operating conditions, the highest clarity of the juices was identified despite low permeate flux. The desired properties of juices, including pH, citric acid content, and total soluble solids, were unaffected by pretreatment and tangential membrane filtration, whereas the pectin content, which reduces the juice quality, was eliminated entirely. Furthermore, fouling analysis was carried out using Hermia's models, and cake filtration was identified to be dominant for both juices. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05734-y.