How do in vitro digestion and cell metabolism affect the biological activity and phenolic profile of grape juice and wine

Cabernet Sauvignon grape juice and wine underwent in vitro digestion, resulting in a reduction of most phenolic compounds (10%-100% decline), notably impacting anthocyanins (82%-100% decline) due to pH variations. However, specific phenolics, including p-hydroxybenzoic, protocatechuic, vanillic, p-coumaric, gallic and syringic acids, and coumarin esculetin, increased in concentration (10%-120%). Grape juice and wine samples showed comparable polyphenolic profile during all phases of digestion. Antioxidant activity persisted, and inhibition of angiotensin-I converting enzyme was improved after the digestion process, likely because of increased concentrations of listed phenolic acids and esculetin. Digested grape juice displayed comparable or superior bioactivity to red wine, indicating it as a promising source of accessible grape polyphenols for a broader audience. Nevertheless, Caco-2 cell model metabolization experiments revealed that only 3 of 42 analyzed compounds passed to the basolateral compartment, emphasizing the significant impact of digestion on polyphenol bioactivity, suggesting potential yet unmeasurable and overlooked implications for human health.

A magnetic imprinted polymer nano-adsorbent with embedded quantum dots and mesoporous carbon for the microextraction of triazine herbicides

A magnetic molecularly imprinted polymer (MMIP) adsorbent incorporating amino-functionalized magnetite nanoparticles, nitrogen-doped graphene quantum dots and mesoporous carbon (MIP@MPC@N-GQDs@Fe3O4NH2) was fabricated to extract triazine herbicides from fruit juice. The embedded magnetite nanoparticles simplified the isolation of the adsorbent from the sample solution. The N-GQDs and MPC enhanced adsorption by affinity binding with triazines. The MIP layer provided highly specific recognition sites for the selective adsorption of three target triazines. The extracted triazines were determined by high-performance liquid chromatography (HPLC) coupled with diode-array detection (DAD). The developed method exhibited linearity from 1.5 to 100.0 µg L-1 with a detection limit of 0.5 µg L-1. Recoveries from spiked fruit juice samples were in the range of 80.1- 108.4 %, with a relative standard deviation of less than 6.0 %. The developed MMIP adsorbent demonstrated good selectivity, high extraction efficiency, ease of fabrication and use, and good stability.

High-throughput semi-automated emulsive liquid-liquid microextraction for detecting SDHI fungicides in water, juice, and alcoholic beverage samples via UHPLC-MS/MS

Herein, a High-Throughput Semi-automated Emulsive Liquid-Liquid Microextraction (HTSA-ELLME) method was developed to detect Succinate Dehydrogenase Inhibitor (SDHI) fungicides in food samples via UHPLC-MS/MS. The Oil-in-Water (O/W) emulsion comprising a hydrophobic extractant and water was dilutable with the aqueous sample solution. Upon injecting the primary emulsion into the sample solution, a secondary O/W emulsion was formed, allowing SDHI fungicides to be extracted. Subsequently, a NaCl-saturated solution was injected in the secondary O/W emulsion as a demulsifier to rapidly separate the extractant, eliminating the need for centrifugation. A 12-channel electronic micropipette was used to achieve a high-throughput semi-automation of the novel sample pretreatment. The linear range was 0.003-0.3 μg L-1 with R2 > 0.998. The limit of detection was 0.001 μg L-1. The HTSA-ELLME method successfully detected SDHI fungicides in water, juice, and alcoholic beverage samples, with recoveries and relative standard deviations of 82.6-106.9% and 0.8-5.8%, respectively. Unlike previously reported liquid-liquid microextraction approaches, the HTSA-ELLME method is the first to be both high-throughput and semi-automated and may aid in designing pesticide pretreatment processes in food samples.

Widely targeted metabolomics-based analysis of the impact of L. plantarum and L. paracasei fermentation on rosa roxburghii Tratt juice

Rosa roxburghii Tratt fruits (RRT) exhibit extremely high nutritional and medicinal properties due to its unique phytochemical composition. Probiotic fermentation is a common method of processing fruits. Variations in the non-volatile metabolites and bioactivities of RRT juice caused by different lactobacilli are not well understood. Therefore, we aimed to profile the non-volatile components and investigate the impact of L. plantarum fermentation (LP) and L. paracasei fermentation (LC) on RRT juice (the control, CG). There were both similarities and differences in the effects of LP and LC on RRT juice. Both of the two strains significantly increased the content of total phenolic, total flavonoid, and some bioactive compounds such as 2-hydroxyisocaproic acid, hydroxytyrosol and indole-3-lactic acid in RRT juice. Interestingly, compared with L. paracasei, L. plantarum showed better ability to increase the content of total phenolic and these valuable compounds, as well as certain bioactivities. The antioxidant capacity and α-glucosidase inhibitory activity of RRT juice were notably enhanced after the fermentations, whereas its cholesterol esterase inhibitory activity was reduced significantly. Moreover, a total of 1466 metabolites were identified in the unfermented and fermented RRT juices. There were 278, 251 and 134 differential metabolites in LP vs CG, LC vs CG, LC vs LP, respectively, most of which were upregulated. The key differential metabolites were classified into amino acids and their derivatives, organic acids, nucleotides and their analogues, phenolic acids and alkaloids, which can serve as potential markers for authentication and discrimination between the unfermented and lactobacilli fermented RRT juice samples. The KEGG enrichment analysis uncovered that metabolic pathways, purine metabolism, nucleotide metabolism and ABC transporters contributed mainly to the formation of unique composition of fermented RRT juice. These results provide good coverage of the metabolome of RRT juice in both unfermented and fermented forms and also provide a reference for future research on the processing of RRT or other fruits.

Health effects of 100% fruit and vegetable juices: evidence from human subject intervention studies

The health effects of 100% fruit and vegetable juices (FVJ) represent a controversial topic. FVJ contain notable amounts of free sugars, but also vitamins, minerals, and secondary compounds with proven biological activities like (poly)phenols and carotenoids. The review aimed to shed light on the potential impact of 100% FVJ on human subject health, comprehensively assessing the role each type of juice may have in specific health outcomes for a particular target population, as reported in dietary interventions. The effects of a wide range of FVJ (orange, grapefruit, mandarin, lemon, apple, white, red, and Concord grapes, pomegranate, cranberry, chokeberry, blueberry, other minor berries, sweet and tart cherry, plum, tomato, carrot, beetroot, and watermelon, among others) were evaluated on a series of outcomes (anthropometric parameters, body composition, blood pressure and vascular function, lipid profile, glucose homeostasis, biomarkers of inflammation and oxidative stress, cognitive function, exercise performance, gut microbiota composition and bacterial infections), providing a thorough picture of the contribution of each FVJ to a health outcome. Some juices demonstrated their ability to exert potential preventive effects on some outcomes while others on other health outcomes, emphasising how the differential composition in bioactive compounds defines juice effects. Research gaps and future prospects were discussed. Although 100% FVJ appear to have beneficial effects on some cardiometabolic health outcomes, cognition and exercise performance, or neutral effects on anthropometric parameters and body composition, further efforts are needed to better understand the impact of 100% FVJ on human subject health.

Continuous-Flow High-Pressure Homogenization of Blueberry Juice Enhances Anthocyanin and Ascorbic Acid Stability during Cold Storage

Blueberries (Vaccinium section Cyanococcus) have a wealth of bioactive compounds, including anthocyanins and other antioxidants, that offer significant health benefits. Preserving these compounds and maintaining the sensory and nutritional qualities of blueberry products such as juice during cold market storage is critical to meet consumer expectations for nutritious, safe, and minimally processed food. In this study, we compared the effects of two preservation processing techniques, high-temperature short-time (HTST) and continuous flow high-pressure homogenization (CFHPH), on blueberry juice quality during storage at 4 °C. Our findings revealed that inlet temperature (Tin) of CFHPH processing at 4 °C favored anthocyanin retention, whereas Tin at 22 °C favored ascorbic acid retention. After 45 days of storage, CFHPH (300 MPa, 1.5 L/min, 4 °C) juice retained up to 54% more anthocyanins compared to control at 0 day. In contrast, HTST treatment (95 °C, 15 s) initially increased anthocyanin concentrations but led to their subsequent degradation over time, while also significantly degrading ascorbic acid. Furthermore, CFHPH (300 MPa, 4 °C) juice had significantly lower polyphenol oxidase activity (>80% less than control), contributing to the overall quality of the juice. This innovative processing technique has the potential to improve commercial blueberry juice, and help meet the rising demand for healthy and appealing food choices.

Enhancing Acid Resistance of Aspergillus niger Pectin Lyase through Surface Charge Design for Improved Application in Juice Clarification

Pectin lyases (PNLs) can enhance juice clarity and flavor by degrading pectin in highly esterified fruits, but their inadequate acid resistance leads to rapid activity loss in juice. This study aimed to improve the acid resistance of Aspergillus niger PNL pelA through surface charge design. A modification platform was established by fusing pelA with a protein tag and expressing the fusion enzyme in Escherichia coli. Four single-point mutants were identified to increase the surface charge using computational tools. Moreover, the combined mutant M6 (S514D/S538E) exhibited 99.8% residual activity at pH 3.0. The M6 gene was then integrated into the A. niger genome using a multigene integration system to obtain the recombinant PNL AM6. Notably, AM6 improved the light transmittance of orange juice to 45.3%, which was 8.39 times higher than that of pelA. In conclusion, AM6 demonstrated the best-reported acid resistance, making it a promising candidate for industrial juice clarification.

A multilevel investigation to reveal the regulatory mechanism of lignin accumulation in juice sac granulation of pomelo

Granulation of juice sacs is a physiological disorder, which affects pomelo fruit quality. Here, the transcriptome and ubiquitinome of the granulated juice sacs were analyzed in Guanxi pomelo. We found that lignin accumulation in the granulated juice sacs was regulated at transcription and protein modification levels. In transcriptome data, we found that the genes in lignin biosynthesis pathway and antioxidant enzyme system of the granulated juice sacs were significantly upregulated. However, in ubiquitinome data, we found that ubiquitinated antioxidant enzymes increased in abundance but the enzyme activities decreased after the modification, which gave rise to reactive oxygen species (ROS) contents in granulated juice sacs. This finding suggests that ubiquitination level of the antioxidant enzymes is negatively correlated with the enzyme activities. Increased H2O2 is considered to be a signaling molecule to activate the key gene expressions in lignin biosynthesis pathway, which leads to the lignification in granulated juice sacs of pomelo. This regulatory mechanism in juice sac granulation of pomelo was further confirmed through the verification experiment using tissue culture by adding H2O2 or dimethylthiourea (DMTU). Our findings suggest that scavenging H2O2 and other ROS are important for reducing lignin accumulation, alleviating juice sac granulation and improving pomelo fruit quality.

Bioprocess optimization for food-grade cellulolytic enzyme production from sorghum waste in a novel solid-state fermentation bioreactor for enhanced apple juice clarification

Transforming global agricultural waste into eco-friendly products like industrial enzymes through bioconversion can help address sustainability challenges aligning with the United Nations' Sustainable Development Goals. Present study explored the production of high-yield food-grade cellulolytic enzymes from Trichoderma reesei MTCC 4876, using a novel media formulation with a combination of waste sorghum grass and cottonseed oil cake (3:1). Optimization of physical and environmental parameters, along with the screening and optimization of media components, led to an upscaled process in a novel 6-L solid-state fermentation (SSF)-packed bed reactor (PBR) with a substrate loading of 200 g. Saturated forced aeration proved crucial, resulting in high fungal biomass (31.15 ± 0.63 mg glucosamine/gm dry fermented substrate) and high yield cellulase (20.64 ± 0.36 FPU/g-ds) and xylanase (16,186 ± 912 IU/g-ds) production at an optimal airflow rate of 0.75 LPM. The PBR exhibited higher productivity than shake flasks for all the enzyme systems. Microfiltration and ultrafiltration of the crude cellulolytic extract achieved 94% and 71% recovery, respectively, with 13.54 FPU/mL activity in the cellulolytic enzyme concentrate. The concentrate displayed stability across wide pH and temperature ranges, with a half-life of 24.5-h at 50 °C. The cellulase concentrate, validated for food-grade safety, complies with permissible limits for potential pathogens, heavy metals, mycotoxins, and pesticide residue. It significantly improved apple juice clarity (94.37 T%) by reducing turbidity (21%) and viscosity (99%) while increasing total reducing sugar release by 63% compared with untreated juice. The study also highlighted the potential use of lignin-rich fermented end residue for fuel pellets within permissible SOx emission limits, offering sustainable biorefinery prospects. Utilizing agro wastes in a controlled bioreactor environment underscores the potential for efficient large-scale cellulase production, enabling integration into food-grade applications and presenting economic benefits to fruit juice industries.

Influence of intensity ultrasound on rheological properties and bioactive compounds of araticum (Annona crassiflora) juice

The use of extracts rich in bioactive compounds is becoming increasingly common in the food, cosmetics, and pharmaceutical industries for the production of functional products. Araticum is a potential fruit to be analyzed due to its content of phenolic compounds, carotenoids and vitamins, with antioxidant properties. Therefore, this study aimed to investigate the effect of ultrasound on total phenolic compounds, total carotenoids, ascorbic acid, color, turbidity and rheology in araticum juice. Response surface methodology based on a central composite design was applied. Araticum juice was subjected to sonication at amplitude levels ranging from 20 to 100 % of the total power (400 W) at a constant frequency of 20 kHz for different durations (2 to 10 min). Morphological analysis was conducted to observe microscopic particles, and viscosity and suitability to rheological models (Newtonian, Power Law, and Herschel-Bulkley) were assessed. The ultrasonic probe extraction method was compared to the control juice. According to the responses, using the desirability function, the optimal conditions for extraction were determined to be low power (low amplitude) applied in a short period of time or low power applied in a prolonged time. These conditions allowed an ultrasonic probe to act on releasing bioactive compounds without degrading them. All three rheological models were suitable, with the Power Law model being the most appropriate, exhibiting non-Newtonian pseudoplastic behavior.

Biochemical characterization of a novel acid-active endopolygalacturonase for pectin depolymerization, pectic-oligomer production, and fruit juice clarification

Endopolygalacturonases are crucial pectinases known for their efficient and sustainable pectin depolymerization activities. The present study identified a novel gene encoding endopolygalacturonase from an acidic mine tailing metagenome. The putative gene showed a maximum identity of 67.55 % with an uncharacterized peptide sequence from Flavobacterium fluvii. The gene was cloned and expressed in a heterologous host, E. coli. Biochemical characterization of the novel endopolygalacturonase enzyme variant (EPHM) showed maximum activity at 60 °C and at 5.0 pH, while retaining 50 % activity under the temperature and pH range of 20 °C to 70 °C for 6 h, and 3.0 to 10.0 for 3 h, respectively. The enzyme exhibited tolerance to different metal ions. EPHM was characterized for the depolymerization of methylated pectin into pectic oligosaccharides. Further, its utility was established for fruit juice clarification, as endorsed by high transmittance, significant viscosity reduction, and release of reducing sugars in the treated fruit juice samples.

Comparison of vitamin C and flavanones between freshly squeezed orange juices and commercial 100% orange juices from four European countries

Knowing the true levels of nutrients and dietary bioactives in fruit juices at the point of consumption is key to properly understand their potential health benefits. The objective was to characterise the vitamin C and flavanone content in commercial orange juices consumed in Europe, compared with fresh-squeezed juices. Commercial juices were a rich source of vitamin C (>30% of the Nutrient Reference Value). Vitamin C in fresh-squeezed juices, at the end of their shelf-life, remained 33% higher than the levels found in the commercial juices. Flavanones had similar values from both commercial and fresh juices, except for fresh samples stored for 48 h, where fresh juices had higher values (22.36 mg/100 mL). Thus, orange juices preserve their bioactive compounds during storage, with very little influence of the brand, country, industrial process or storage conditions. Main bioactive compounds in commercial juices are present at nutritionally significant levels to the freshly-squeezed ones.

Vortex-assisted dispersive micro-solid-phase extraction using silica-supported Fe2O3-modified khat (Catha edulis) biochar nanocomposite followed by GC-MS for the determination of organochlorine pesticides in juice samples

In this paper, dispersive micro-solid phase extraction technique was developed for the purpose of extracting and preconcentrating organochlorine pesticide residues in juice samples before their separation and quantitative analysis by gas chromatography-mass spectrometry. A sorbent composed of a silica-supported Fe2O3-modified khat leftover biochar nanocomposite (SiO2-Fe2O3-KLBNC) was implemented in the process. To improve the dispersion of the sorbent in the solution, vortex mixer was employed. Experimental parameters influencing the performance of the method were optimized, and the optimal conditions were established. With these conditions, linear dynamic ranges ranged from 0.003 to 100.0 ng/mL were achieved, with a correlation coefficient (r2) ≥ 0.9981. The limits of detection and quantification, determined by signal-to-noise ratios of 3 and 10, respectively, were found to be in the ranges of 0.001-0.006 ng/mL and 0.003-0.020 ng/mL. Intra- and inter-day precision, values ranging from 0.3-4.8% and 1.7-5.2% were obtained, respectively. The matrix-matched extraction recoveries demonstrated favorable outcomes, falling within the range of 83.4-108.3%. The utilization of khat leftover as an adsorbent in contemporary sample preparation methodologies offers a cost-effective alternative to the currently available, yet expensive, adsorbents. This renders it economically viable, particularly in resource-constrained regions, and is anticipated to witness widespread adoption in the coming future.

Increased nitrate intake from beetroot juice over 4 weeks affects nitrate metabolism, but not vascular function or blood pressure in older adults with hypertension

The decline in vascular function and increase in blood pressure with aging contribute to an increased cardiovascular disease risk. In this randomized placebo-controlled crossover study, we evaluated whether previously reported cardiovascular benefits of plant-derived inorganic nitrate via nitric oxide (NO) translate into improved vascular function and blood pressure-lowering in 15 men and women (age range: 56-71 years) with treated hypertension. We investigated the effects of a single ∼400 mg-dose at 3 hours post-ingestion (3H POST) and the daily consumption of 2 × ∼400 mg of nitrate through nitrate-rich compared with nitrate-depleted (placebo) beetroot juice over 4 weeks (4WK POST). Measurements included nitrate and nitrite in plasma and saliva; endothelial-dependent and -independent forearm blood flow (FBF) responses to acetylcholine (FBFACh) and glyceryltrinitrate (FBFGTN); and clinic-, home- and 24-hour ambulatory blood pressure. Compared to placebo, plasma and salivary nitrate and nitrite increased at 3H and 4WK POST following nitrate treatment (P < 0.01), suggesting a functioning nitrate-nitrite-NO pathway in the participants of this study. There were no differences between treatments in FBFACh and FBFGTN-area under the curve (AUC) ratios [AUC ratios after (3H POST, 4WK POST) compared with before (PRE) the intervention], or 24-hour ambulatory blood pressure or home blood pressure measures (P > 0.05). These findings do not support the hypothesis that an increased intake of dietary nitrate exerts sustained beneficial effects on FBF or blood pressure in hypertensive older adults, providing important information on the efficacy of nitrate-based interventions for healthy vascular aging. This study was registered under ClinicialTrials.gov (NCT04584372).

Quantifying chemical correlations between fruits and processed fruit products: A non-targeted analysis approach

Juices and beverages are produced by industry for long-distance distribution and shelf-stability, providing valuable nutrients. However, their nutritional value is often underestimated due to insufficient analytical methods. We have employed non-targeted analysis through a standardized analytical protocol, taking advantage of Data Independent Acquisition (DIA) technique and a novel Chromatographic Retention Behavior (CRB) data deconvolution algorithm. After analyzing 9 fruits and their products, correlations between fruits and their juices are accurately digitalized by similarities of their LC-MS fingerprints. We also specify non-targeted molecules primarily associate with nutrient loss in these analyzed juice products, including nitrogenous nutrients, flavonoids, glycosides, and vitamins. Moreover, we unveiled previously unreported fruit-characteristic metabolites, of which reconstituted-from-concentrate (RFC) juices contain over 40% of the content found in their fresh counterparts. Conclusively, our method establishes a quantitative benchmark for rational selection of RFC juices to substitute natural fruits.

Effects of juicing methods on the bioactive compounds and flavor quality of 'Black-seed' pomegranate from three producing areas

BACKGROUND

Color, nutrients and flavor are the key characteristics of pomegranate juice, but they are susceptible to processing methods and raw materials. In this study, the effects of aril juicing and whole fruit juicing methods on the composition of 'Black-seed' pomegranate juice from three producing areas were studied, including physicochemical parameters, color attributes, organic acids, sugars, phenolic compounds, and volatile compounds.

RESULTS

The whole fruit juicing method resulted in higher juice yields of pomegranate fruit with 69.01-72.59%, hue angle values were 5.95-6.45°, and the juice remained red. The highest level of citric acid (21.21 g L-1 ), total acids (24.78 g L-1 ), and total anthocyanin content (435.59 mg L-1 ) were found in whole fruit juice, and seven tannins were detected. The most abundant volatile compounds were (Z)-3-hexen-1-ol and 1-hexanol in all juice samples, with alcohol content increased and aldehydes content decreased by whole fruit juicing. Principal component analysis revealed that the 24 indexes (variable important in projection >1) clearly distinguished juice samples obtained by two juicing methods, with ellagic acid hexoside, (E)-2-heptenal, (+)-catechin, and octanoic acid having the best discriminatory potential.

CONCLUSION

Overall, the effects of juicing method on 'Black-seed' pomegranate juice were greater than those of raw-material-producing areas. These results confirmed the potential for using the whole 'Black-seed' pomegranate for processing, and also provided a theoretical basis for the healthy product development and utilization of dark-color pomegranate varieties. © 2023 Society of Chemical Industry.

Assessment of phthalate esters in packaged fruit juices sold in the Turkish market and their implications on human health risk

The objective of this study was to analyze the concentration of PAEs and conduct a risk assessment focusing on their potential non-carcinogenic and carcinogenic effects as endocrine-disrupting chemicals. In this research, a method of quantifying eight PAEs in fruit juice samples was established through the utilization of dispersive solid-phase extraction (dSPE) and Liquid Chromatography coupled with Tandem Mass Spectrometry (LC-MS/MS). While he method recoveries for the samples ranged from 92.21 % to 96.74 %, the RSDs for the eight analytes in the samples ranged from 4.22 % to 6.64 %. Additionally, LODs ranging from 0.34 to 1.88 ng/mL and LOQs ranging from 1.17 to 6.27 ng/mL were determined. Utilizing this methodology, the assessment of PAE concentrations was carried out in 48 fruit juice samples. The results showed that PAEs were detectable in the fruit juice samples, but all tested compounds remained below the specific migration limits set by the EU (30 mg/kg for BBP, 1.5 mg/kg for DEHP, 0.3 mg/kg for DBP, and 9 mg/kg for DINP and DIDP). Among the analyzed PAEs, DINP (26.94 ± 3.25 ng/mL), DEP (7.07 ± 7.59 ng/mL), and DEHP (3.48 ± 1.02 ng/mL) were found to be the most prevalent plasticizers in the fruit juices. Health risk assessments were conducted by calculating Hazard Quotient (HQ) and Hazard Index (HI) values based on the consumption patterns of different age groups. The findings indicated that the values for DEHP, DINP, DEP, and DBP were all below 1, indicating negligible non-carcinogenic health risks associated with the consumption of fruit juices across all age groups. Moreover, the dietary intake levels of each PAE were found to be below the values established by the EFSA for TDI.

An accurate and sensitive determination of selected pesticides in mixed fruit juice samples using the combination of a simple and efficient microextraction method and GC-MS with a matrix matching calibration strategy

Pesticides have been used on several fruits, vegetables and cereals to control harmful organisms in order to increase the quality of products; however, these substances cause serious health effects. Therefore, an accurate and sensitive analytical method should be developed for the determination of pesticides to evaluate their toxicity. In this study, an efficient microextraction strategy was applied to preconcentrate eight different selected pesticides from mixed fruit juice samples prior to gas chromatography-mass spectrometry detection. All significant parameters such as spraying number, extraction solvent type, sample volume and mixing type/period belonging to the developed extraction method were elaborately optimized to get low detection limits. After the optimization studies, system analytical performance studies were carried out and limit of detection (LOD) values varied from 0.04 μg /kg-1 to 1.99 μg kg-1 (mass based) for the selected analytes. Under the optimum experimental conditions, spiking recovery experiments were performed in the mixed fruit juice samples to evaluate the applicability and accuracy of the proposed method. The recovery results were recorded in the range of 81.4-123.5% with acceptable standard deviations by applying a matrix matching calibration strategy. The proposed analytical method can be used for the qualitative and quantitative determination of selected pesticides in the mixed fruit juice samples and can also be applied to other fruit juice samples using a matrix matching calibration strategy.

Determination of thiram in fruit juices using a bacterial cellulose nanocrystal-based SERS substrate

Pesticide residues in agri-foods have risk to human health and one solution is to develop simple and accurate methods for rapid detection. We developed a SERS sensor composed of gold nanoparticles (AuNPs) and bacterial cellulose nanocrystal (BCNC) to detect thiram in fruit juice. BCNC-SO3H was used as a stabilizer to support AuNPs via electrostatic repulsion, fabricating a BCNC-AuNPs SERS substrate with uniformly distributed AuNPs. This BCNC-AuNPs SERS substrate was applied to determine thiram residues in peach juice, apple juice, and grape juice with the limits of detection of 0.036 ppm, 0.044 ppm, and 0.044 ppm, respectively. The whole test took 12 min including sample preparation and analysis. The detection limits meet the maximum residue levels of thiram in fruit juices required by China, Europe and North America, indicating that this BCNC-based substrate could serve as a satisfactory SERS sensor for pesticide residue monitoring in the food supply chain.

Ternary solvent based homogeneous liquid-liquid microextraction for the preconcentration of organochlorine pesticides from water and apple juice samples

In the present study, the optimal experimental conditions were determined by optimizing the effect of extraction solvent types and volume, salt types and concentration, centrifugation speed and time using one variable at a time. Under optimal experimental conditions, calibration curves were constructed separately using water and apple juice samples as representative matrices, and good linearities were achieved over a wide concentration range of 0.2-1600 ng L-1 with a coefficient of determination (r2) ≥ 0.998. The limits of detection (LOD) and limits of quantification (LOQ), determined to be 3 and 10 times the signal-to-noise ratios (S/N), were between 0.07-3.9 and 0.2-12.0 ng L-1 for water samples and 2.6-10.0 and 8.0-30.0 ng L-1 for the apple juice sample respectively. The precisions study showed %RSD values of ≤6% for both matrices, indicating satisfactory precisions. The enrichment factors and recoveries of the proposed method ranged from 41.4-74.5 and 86-109% respectively. The proposed method could be used as a simple and environmentally friendly alternative for the analysis of OCPs from environmental and food matrices. This method potentially offers a more sustainable and effective approach to monitoring OCPs in environmental and food products. Its use in the analysis of apple juice samples is particularly novel and can provide valuable insights into pesticide contamination in fruit juices.

Effect of lactic acid bacteria co-fermentation on antioxidant activity and metabolomic profiles of a juice made from wolfberry and longan

Lactic acid bacteria (LAB) fermentation is frequently employed to improve the nutritional, functional, and sensory characteristics of foods. Our study explored the effects of co-fermentation with Lacticaseibacillus paracasei ZH8 and Lactococcus lactis subsp. lactis YM313 on the physicochemical properties, antioxidant activity, and metabolomic profiles of wolfberry-longan juice (WLJ). Fermentation was carried out at 35 °C for 15 h. The results suggest that WLJ is a favorable substrate for LAB growth, reaching a total viable count exceeding 8 log CFU/mL after fermentation. LAB fermentation increased acidity, reduced the sugar content, and significantly impacted the juice color. The total phenolic and flavonoid contents of the WLJ and the antioxidant capacities based on 2,2-diphenyl-1-picrylhydrazyl (DPPH), ABTS radical scavenging abilities and FRAP were significantly improved by LAB fermentation. Nontargeted metabolomics analysis suggested that the contents of small molecule substances in WLJ were considerably affected by LAB fermentation. A total of 374 differential metabolites were identified in the juice before and after fermentation, with 193 significantly upregulated metabolites and 181 siginificantly downregulated metabolites. The regulation of metabolites is important for improving the flavor and functions of juices, such as L-eucylproline, Isovitexin, Netivudine, 3-Phenyllactic acid, vanillin, and ethyl maltol, ect. This study provides a theoretical foundation for developing plant-based foods fermented with LAB.

Analytical determination of tryptoquialanines A and B: Ensuring the quality and safety of orange juices

Although orange juice is a popular beverage worldwide, fruit distribution, storage, and processing can facilitate fungal infection by Penicillium digitatum; leading to the production of tremorgenic alkaloids, specifically tryptoquialanines A (TA) and B (TB). An Analytical method was developed and validated based on QuEChERS and LC-MS/MS analysis to determine the levels of TA and TB in fresh, industrial, and homemade orange juices. Excellent linearity was observed in the method over a high range of 1-1000 μg/kg and low range of 1-75 μg/kg with R2 ≥ 0.998. The LOD and LOQ were 1 and 3 μg/kg, respectively. Recoveries showed values between 57 and 83 %, with RSD ≤ 13 %. Our data indicated a higher prevalence of mycotoxin TA in fresh and industrial orange juices. Reduction in TA and TB content after thermal and HPP treatments were ≤ 32 %. However, thermal treatment was more effective in reducing TA and TB contents.

Biohybrid Adsorbent for the Preconcentration of Lead and Its Determination in Fruit Juices by Electrothermal Atomic Absorption Spectrometry

BACKGROUND

Fruit juices are one of the most non-alcoholic beverages consumed in the world. Essential elements and other nutrients present in fruit juices play an important role in human well-being. However, fruit juices may also contain potentially toxic elements at trace levels, causing health risks.

OBJECTIVE

The objective of this work was to develop an analytical methodology based on the preconcentration of lead using a new biodegradable hybrid material (BHM) composed of Rhodococcus erythropolis AW3 bacteria and Brassica napus hairy roots.

METHODS

The BHM was implemented in an online solid-phase extraction (SPE) system for the determination of lead in fruit juices by electrothermal atomic absorption spectrometry (ETAAS).

RESULTS

Effects of critical parameters on lead retention were studied. Under optimal experimental conditions, extraction efficiency higher than 99.9% and an enrichment factor of 62.5 were achieved. The dynamic capacity of the BHM was 36 mg/g, which favored the reuse of the column for at least eight biosorption-desorption cycles. The LOD and LOQ for preconcentration of 5 mL of sample were 5.0 and 16.5 ng/L lead, respectively. The RSD was 4.8% (at 1 µg/L lead and n = 10).

CONCLUSION

The developed method was suitable for application to lead determination in different types of fruit juice.

HIGHLIGHTS

A novel microextraction procedure based on the use of a biohybrid adsorbent. Highly sensitive determination of Pb at trace levels. Analysis of Pb in fruit juices samples. An eco-friendly microextraction technique for Pb determination.

Effect of dielectric barrier discharge nonthermal plasma treatment on physicochemical, nutritional, and phytochemical quality attributes of pineapple [Ananas comosus (L.)] juice

Forward feed multilayered perception and central composite rotatable design were used to model the nonthermal plasma (NTP) experimental data in artificial neural network (ANN) and response surface methodology, respectively. The ANN was found to be more accurate in modeling the experimental dataset. The NTP process parameters (voltage and time) were optimized for pineapple juice within the range of 25-45 kV and 120-900 s using an ANN coupled with the genetic algorithm (ANN-GA). After 176 generations of GA, the ANN-GA approach produced the optimal condition, 38 kV and 631 s, and caused the inactivation of peroxidase (POD) and bromelain by 87.24% and 51.04%, respectively. However, 100.32% of the overall antioxidant capacity and 89.96% of the ascorbic acid were maintained in the optimized sample with a total color change (ΔE) of less than 1.97 at all plasma treatment conditions. Based on optimal conditions, NTP provides a sufficient level of POD inactivation combined with excellent phenolic component extractability and high antioxidant retention. Furthermore, plasma treatment had an insignificant effect (p > 0.05) on the physicochemical attributes (pH, total soluble solid, and titratable acidity) of juice samples. From the intensity peak of the Fourier-transform infrared spectroscopy analysis, it was found that the sugar components and phenolic compounds of plasma-treated juice were effectively preserved compared to the thermal-treated juice.

Evaluation of the Antioxidant Capacity of Fruit Juices by Two Original Analytical Methods

Two analytical methods previously developed by our groups were employed to estimate the antioxidant capacity of commercial fruit juices. The electrochemical method, which measures the scavenging activity of antioxidants towards OH radicals generated by both hydrogen peroxide photolysis and Fenton's reaction, is based on the recovery of the cyclic voltametric response of the redox probe Ru(NH3)63+ at a Glassy Carbon electrode modified with a thin film of an insulating polyphenol, in the presence of compounds with antioxidant properties. The values of the antioxidant capacity of the fruit juices are expressed as vitamin C equivalents/L. The chromatographic method is based on the generation of OH radicals via Fenton's reaction in order to test the inhibition of their formation in the presence of antioxidant compounds by monitoring salicylate aromatic hydroxylation derivatives as markers of •OH production, by means of HPLC coupled to coulometric detection. The results are expressed as the percentage of inhibition of •OH production in the presence of the tested juice compared to the control sample. When OH radicals are produced by Fenton's reaction, the antioxidant capacity of the juices, estimated by both methods, displays an analogous trend, confirming that they can be considered an alternative for measuring the ability of antioxidants to block OH radical formation.

Development of homogeneous dispersive solid phase extraction using albumin as a green sorbent and its combination with dispersive liquid-liquid microextraction: application in extraction of pesticides from fruit juices

In the current study, salt- and pH-induced homogeneous dispersive solid phase extraction was developed using albumin as a sorbent for the extraction of some pesticides (diazinon, diniconazole, haloxyfop-R-methyl, and hexaconazole) from fruit juice of orange, pomegranate, and barberry. The extracted analytes were more concentrated by dispersive liquid-liquid microextraction to obtain high enrichment factors and low detection limits prior to their determination by gas chromatography-mass spectrometry. In the extraction process, human serum albumin solution was added to the sample solution at the μL-level and a homogeneous solution was obtained. Then, albumin was precipitated into the solution by adding an inorganic salt and decreasing the solution pH. By doing so, the analytes were adsorbed by albumin effectively due to their high adsorption capacity and large surface area. Following this, the pesticides were eluted from the albumin sorbent using an elution solvent and used in a dispersive liquid-liquid microextraction step. Under the optimum extraction conditions, low limits of detection and quantification were achieved in the ranges of 0.02-0.04 and 0.07-0.13 ng mL-1, respectively. The calibration curves were linear in the range of 0.13-250 ng mL-1. Relative standard deviation as a criterion for precision and the method repeatability were in the ranges of 2.9-4.2% for intra- (n = 5, C = 5 or 50 ng mL-1) and 3.2-5.2% for inter-day (n = 5, 50 ng mL-1) precisions. The enrichment factors and extraction recoveries were in the ranges of 390-460 and 78-92%, respectively. Finally, the offered procedure was applied for the analysis of pesticide residues in some fruit juice samples.

Comparing the antioxidant properties and volatile compounds of carrot-orange juice blend processed through varied chemical, pasteurization and ultrasound conditions

Ultrasound technique is one of the green technologies that is being utilized widely for varying food processes. Our aim in this study was to carry out ultrasonication, pasteurization and chemical preservation (Potassium metabisulfite) techniques on a carrot-orange juice blend. Additionally, the effect of these treatments on the storage period of about 21 days was also determined. The study displayed an array of results under the effect of different treatments. Throughout the storage period of 21 days' significant results were presented by the carrot juice blend subjected to the ultrasound technique (25 min) giving the highest values for total phenolic content (25.56 ± 1.29 mg GAE/100 mL), total antioxidant activity (573.48 ± 2.29 mg Trolox /100 mL), DPPH (32.32 ± 1.83 %) and reducing power (45.45 ± 1.92 mg AAE/100 mL) with least deterioration, followed by the blends treated with potassium metabisulfite (KMS) and pasteurization. The physicochemical analysis showed a non-significant effect of treatments on pH and total soluble solids (oBrix) of carrot-orange juice blends whereas, the changes in color parameters L*, a* and b* were noted to show changes in treated blends. Similarly, the results for the GC-MS quantification of volatile compounds displayed the highest concentrations in the ultrasonicated blends as compared to other techniques. The peak quantity was obtained for the hexanal (9903.43 ± 7.61 μg.kg-1) followed by 3-Methylbutanal (2638.7 ± 5.44 μg.kg-1), terpinolene (2337.16 ± 5.28 μg.kg-1), elemicin (2198.28 ± 5.28 μg.kg-1), myristicin (1936.62 ± 6.72 μg.kg-1). The use of sonication can effectively enhance the nutritional qualities of juice, as perceived by consumers.

Occurrence of Alicyclobacillus acidoterrestris in pasteurized and high hydrostatic pressure-treated fruit juices and isolates' characterization

In recent years, acidophilic, heat-resistant, and spore-forming spoilage bacteria have been identified in pasteurized or treated by high hydrostatic pressure (HPP) fruit juices. Alicyclobacillus acidoterrestris is the bacteria more frequently linked to the spoilage of this type of product because its spores can survive conventional pasteurization and HPP treatments. Under favourable conditions, such as an acidic pH, its spores can germinate and multiply, with the consequent production of guaiacol. Guaiacol is a compound with an undesirable odour ("medicinal", "smoked" or "antiseptic"). In this context, our objective was to determine the prevalence of A. acidoterrestris in 150 Spanish pasteurized and HPP-treated fruit juices purchased from supermarkets or received from manufacturers. Then, the isolates and the reference strain (CECT 7094 T) were characterized to establish differences in terms of (i) growth capacity at different pH and temperatures, and in (ii) guaiacol production capacity. The results showed a high incidence of A. acidoterrestris (18.0 %) in the analysed juices. The 44.4 % of the isolates came from blends of fruit juices. Within juice blends, 9 juices contained apple juice among their ingredients. This represents a 18.8 % of incidence with respect to the total of blended juices with apple. A high incidence in monovarietal apple juices was also observed (3 out of 14 samples). Regarding the characterization of the isolates, EC1 (isolated from an apple concentrate) showed the highest growth capacity at pH 4.0 at temperatures from 20 to 55 °C. Besides, three strains (R42, EC10, and EZ13, isolated from clementine, plum and white grape juice, respectively) could grow at room temperatures (20 and 25 °C). For pH, only EZ13, isolated from white grape juice, was able to grow significantly at pH 2.5. Finally, the production of guaiacol ranged from 74.1 to 145.6 ppm, being the isolate EC1 the one that produced more guaiacol after 24 h of incubation at 45 °C (145.6 ppm). As we have observed, there is a high incidence of A. acidoterrestris in marketed juices and intermediate products despite the treatments received (pasteurization or HPP). Under favourable conditions for the development of this microorganism, it could produce enough guaiacol to spoil the juices before their consumption. Therefore, in order to improve the quality of fruit juices it is necessary to investigate in more detail the origin of this microorganism and to find strategies to reduce its presence in final products.

Thermosonication of Orange-Carrot Juice Blend: Overall Quality during Refrigerated Storage, and Sensory Acceptance

Ultrasound combined with high temperatures (thermosonication) is an alternative to thermal treatments applied for juice preservation purposes. Blend juices, such as orange-carrot juice, are an interesting option for consumers due to their diversity of unique flavors. The main aim of the present study is to investigate thermosonication's impact on the overall quality of an orange-carrot juice blend over 22-day storage at 7 °C, in comparison to thermal treatment. Sensory acceptance was assessed on the first storage day. The juice blend was prepared based on using 700 mL of orange juice and 300 g of carrot. The effect of ultrasound treatment at 40, 50, and 60 °C for 5 and 10 min, as well as of thermal treatment at 90 °C for 30 s, on the physicochemical, nutritional, and microbiological quality of the investigated orange-carrot juice blend was tested. Both the ultrasound and the thermal treatment could maintain pH, °Brix, total titratable acidity, total carotenoid content, total phenolic compounds, and the antioxidant capacity of untreated juice samples. All ultrasound treatments improved samples' brightness and hue value, and made the juice brighter and redder. Only ultrasound treatments at 50 °C/10 min and at 60 °C/10 min have significantly reduced total coliform counts at 35 °C. Thus, they were selected along with untreated juice for sensory analysis, whereas thermal treatment was used for comparison purposes. Thermosonication at 60 °C for 10 min recorded the lowest scores for juice flavor, taste, overall acceptance, and purchase intention. Thermal treatment and ultrasound at 60 °C for 5 min recorded similar scores. Minimal variations in quality parameters were observed over 22-day storage in all treatments. Thermosonication at 60 °C for 5 min has improved samples' microbiological safety and resulted in good sensorial acceptance. Although thermosonication has the potential to be used in orange-carrot juice processing, further investigations are necessary to enhance its microbial effect on this product.

Freeze dried pomegranate juices of Moroccan fruits: main representative phenolic compounds

BACKGROUND

The pomegranate (Punica granatum) is an ancient perennial plant species of the Punicaceae family. Its seeds are consumed as food or as juice. Previous studies have noted that pomegranate juice encompasses many active compounds with beneficial effects. The main goals of this work were to study the phenolic components of freeze-dried and reconstituted pomegranate juices obtained from 13 pomegranate genotypes growing in Morocco.

RESULTS

We analyzed several pomegranate juices using high-performance liquid chromatography and high-resolution mass spectrometry to determine phenolic compounds. Twenty-seven bio-phenols, belonging to four different classes (phenolic acids, hydrolyzable tannins, anthocyanins, and flavonoids), were identified based on their accurate mass measurements, and quantified. Some encouraging results were obtained. Even though the freeze-drying process introduced a marked degradation of bio-phenols, substantially lowering their levels in the reconstituted fruit juices, these fruit juices were still rich enough in bio-phenols to compete with some fresh fruit juices. The reconstituted juices obtained by rehydration of the lyophilized material still differed enough to enable a statistical classification based on their polyphenol content. A correlation analysis was applied to the polyphenol data to explore correlations and similarities between genotypes.

CONCLUSIONS

The results showed that freeze-drying and reconstitution of juices introduced some degradation of the polyphenol content. The overall polyphenolic pattern within the same cultivar, in two different harvesting years, was maintained, however, suggesting the composition stability of the freeze-dried juices produced in this time span. © 2022 Society of Chemical Industry.

Health risk assessment of PAHs in fruit juice samples marketed in city of Tehran, Iran

The objective of the present study was to investigate the level of 16 PAHs in fruit juice samples (orange, apple, peach, pineapple, and mango) with three different packages (PET bottle, Tetra Pak, and canned packaging) by using MSPE/GC-MS (magnetic solid-phase extraction and gas chromatography-mass spectrometry) method. In this method limit of detection (LOD), and limit of quantitation (LOQ), and recovery were 0.030-0.280 μg/L, 0.090-0.840 μg/L, and 94.8-102%, respectively. Our results showed the median of total PAHs and PAH4 (in all samples) were 7.67 ± 3.19 and 0.370 ± 0.160 μg/L, respectively. The median of BaP in samples was )0.060 ± 0.030 μg/L( lower than the standard level (0.200 μg/L in drinking water) of US Environmental Protection Agency (USEPA). Also, our results showed that pineapple juice had a maximum median of total PAHs of 12.4 ± 4.84 μg/L and mango juice had a minimum median of total PAHs of 5.17 ± 1.24 μg/L. Additionally, canned packaging had a maximum average total PAHs of 10.6 ± 5.22 μg/L and PET bottles had a minimum average total PAH of 5.25 ± 2.03 μg/L. A heat map approach was also used to cluster samples. The Monte Carlo results indicated that the estimated daily intake (EDI) rank order was Na > B(g)P > Ch > I(cd)P > B(b)F > Ph > B(k)F > F > Ace > Fl > B(a)P > B(a)A > P >A. The Monte Carlo simulation (MCS) results showed the incremental lifetime cancer risk (ILCR) at the 95th percentiles for adults and children was 4.91 × 10^-7 and 9.12 × 10^-7, respectively. It is concluded that the concentration of PAHs compounds in Iranian fruit juices is lower than the existing standards, and in terms of the risk of carcinogenesis, it does not threaten the human health (< 10^-6).

Changes in the Major Odorants of Grape Juice during Manufacturing of Dornfelder Red Wine

Application of the aroma extract dilution analysis (AEDA) on a distillate prepared from freshly squeezed juice of Dornfelder grapes revealed (3Z)-hex-3-enal and trans-4,5-epoxy-(2E)-dec-2-enal with the highest flavor dilution (FD) factors. In contrast, in the final Dornfelder wine prepared thereof, the highest FD factors were found for 2-phenylethyl acetate, 2-phenylethan-1-ol, and (E)-β-damascenone. However, for example, among others, (3Z)-hex-3-enal no longer appeared as an important odorant. To monitor the olfactory changes occurring in single processing steps from Dornfelder grapes to the final wine, selected odorants in grape juice, must, and young as well as aged wine from the same batch of Dornfelder grapes were quantitated. In particular, (3Z)-hex-3-enal and hexanal decreased considerably during mashing, while, as to be expected, the concentrations of yeast metabolites, e.g., odor-active alcohols and esters, drastically increased during fermentation. To reveal the influence of barrel aging, the odorants of the same Dornfelder wine aged in either barrique barrels or steel tanks were compared.

Citrus juice off-flavor during different processing and storage: Review of odorants, formation pathways, and analytical techniques

As the most widespread juice produced and consumed globally, citrus juice (mandarin juice, orange juice, and grapefruit juice) is appreciated for its attractive and distinct aroma. While the decrease of characteristic aroma-active compounds and the formation of off-flavor compounds are easy to occur in processing and storage conditions. This review provides a comprehensive literature of recent research and discovery on citrus juice off-flavor, primarily focusing on off-flavor compounds induced during processing and storage (i.e., thermal, storage, light, oxygen, package, fruit maturity, diseases, centrifugal pretreatment, and debittering process), formation pathways (i.e., terpene acid-catalyzed hydration, caramelization reaction, Maillard reaction, Strecker degradation, and other oxidative degradation) of the off-flavor compounds, effective inhibitor pathway to off-flavor (i.e., electrical treatments, high pressure processing, microwave processing, ultrasound processing, and chemical treatment), as well as odor assessment techniques based on molecular sensory science. The possible precursors (terpenes, sulfur-containing amino acids, carbohydrates, carotenoids, vitamins, and phenolic acids) of citrus juice off-flavor are listed and are also proposed. This review intends to unravel the regularities of aroma variations and even off-flavor formation of citrus juice during processing and storage. Future aroma analysis techniques will evolve toward a colorimetric sensor array for odor visualization to obtain a "marker" of off-flavor in citrus juice.

Impact of crossflow microfiltration on aroma and sensory profiles of a potential functional citrus-based food

BACKGROUND

Citrus juices can be cold-concentrated by crossflow microfiltration (CMF) in order to obtain functional foods enriched in carotenoids, flavonoids and pectins. The work aimed to characterize the organoleptic quality of this type of micronutrient-dense foods through their aroma profile and sensory analysis. Two citrus concentrates with and without a diafiltration step were compared.

RESULTS

Both citrus products were very different, linked to aroma compound, sugar and organic acid contents. Due to its sugar/acidity balance and its better aromatic profile responsible for the citrus-floral flavour, the concentrate without diafiltration was preferred by the sensory panel. Thanks to a simple transfer model, we showed that retention of volatiles clearly varied from one aroma compound to another. The terpene hydrocarbons were the most retained by the membrane during CMF, probably because they were strongly associated with insoluble solids by adsorption.

CONCLUSION

Even though the process modified their organoleptic profiles, both citrus-based products were well rated and can be consumed directly as pleasant functional drinks. © 2022 Society of Chemical Industry.

[Comparative analysis of the total content of polyphenols in some types of industrial juice products]

Fruits are the most important source of polyphenols, substances that have a positive effect on human health. Modern technologies for the industrial processing of fruits into juice are aimed at preserving the useful components of the raw material in it. The issue of the content of polyphenols in industrial juice products, and, especially, changes in their concentration over time, is important for understanding the nutritional value of juice products and requires further study. The purpose of the work is to study the total content of polyphenols depending on the type of juice products and the time elapsed since the product was manufactured. Material and methods. The total content of polyphenols in terms of gallic acid was determined by the Folin-Ciocalteu method in four popular types of juice products (orange, grapefruit and apple juice, cherry nectar), various brands and with different production dates. The results of the determination in 60 product samples selected from Russian retail chains were analyzed. Results. Polyphenols are found in all types of products in significant amounts: in orange juices from 678 to 870 mg/kg, in grapefruit juices from 447 to 798 mg/kg, in apple juices from 264 to 1320 mg/kg, in cherry nectars from 696 to 1090 mg/kg. The highest average content was found in cherry nectars (859±106 mg/kg), followed by orange (781±54 mg/kg) and grapefruit juices (634±91 mg/kg). In apple juices, there is a significant variation in the content of polyphenols depending on the method of juice production - the highest content of polyphenols was found in straight-pressed apple juices (1119±124 mg/kg). The content of polyphenols in products stored for six months or more does not show any significant differences from the content in fresher products, which suggests a consistently high content of polyphenols in juice products throughout the entire shelf life. Conclusion. The study showed the presence of high concentrations of common polyphenols in juice products. The dependence of total polyphenol content on the time elapsed since the production of juice product was not found. Juice products of industrial production can make a significant contribution to the intake of polyphenols in the human body.

Challenges in assessing the quality of fruit juices: Intervening role of biosensors

The quality of packaged fruit juices is affected during their processing, packaging and storage that might cause deteriorative biological, chemical and physical alterations. Consumption of spoiled juices, either from biological or non-biological sources can pose a potential health hazard for the consumers. Sensitive and reliable methods are required to ensure the quality of fruit juices. Standard analytical methods such as chromatography, spectrophotometry, electrophoresis and titration, that require sophisticated equipment and expertise, are traditionally used to assess the quality of fruit juices. Using biosensors, that are simple, portable and rapid presents a promising alternative to the tedious analytical methods for the detection of various degradation and spoilage indicators formed in the packaged fruit juices. Here, we review the challenges in maintaining the quality of fruit juices and the recent developments in techniques and biosensors for quick analysis of fruit juice components.

TiO2@MOF-919(Fe-Cu) as a sorbent for the extraction of benzoylurea pesticides from irrigation water and fruit juices

The TiO₂@MOF-919(Fe-Cu) solid-phase extraction material was prepared by growing MOF-919(Fe-Cu) in situ on three-dimensional radial TiO₂ microspheres by a simple solvothermal method. This combination drew on both the resources of good single dispersion and extraction rate, which made it a better extraction material. It was accompanied with high-performance liquid chromatography (SPE-HPLC) for the separation and determination of four benzoylurea pesticides (triflumuron, chlorbenzuron, teflubenzuron and diflubenzuron) in afforestation irrigation water and juice samples (grape, peach and apple juices). Under the optimal conditions, the linearity of the method ranged from 1 to 400 μg L^-1 with a correlation coefficient (R²) ≥ 0.9994, while the detection limit was in the range of 0.40-0.56 μg L^-1 for the four pesticides. The adopted material showed good reusability and can be used no less than 10 times. The intra-day and inter-day precision were in the range of 1.78-3.24% and 4.06-5.08%, respectively. The proposed method was then successfully applied for the detection of benzoylurea pesticides in the spiked samples with good recoveries (72.3-108.4%) and good precision (5.15%) due to π-π and hydrophobic interactions between the analytes and adsorbent. The results show that the composite had the potential to be used as a SPE adsorbent for the enrichment and extraction of benzene ring structures containing imide groups in actual samples.

Improved magnetic solid-phase extraction based on magnetic sorbent obtained from sand for the extraction of pesticides from fruit juice

BACKGROUND

A combination of magnetic solid-phase extraction using an efficient and cheap magnetic sorbent obtained from sand and dispersive liquid-liquid microextraction has been developed for the extraction of nine multiclass pesticides (clodinafop-propargyl, haloxyfop-R-methyl, fenoxaprop-P-ethyl, oxadiazon, penconazole, diniconazole, chlorpyrifos, fenazaquin, and fenpropathrin) from commercial fruit juices (sour cherry, pomegranate, grape, watermelon, orange, apricot, and peach juices). The enriched pesticides were determined by gas chromatography-flame ionization detector and gas chromatography-mass spectrometry. The sorbent was natural iron oxide entrapped in silica along with some impurities. In this method, to extract the analytes from the samples, an appropriate amount of the magnetic sorbent (at mg level) is added. Then the sorbent particles are isolated from the solution using an external magnetic field and the adsorbed analytes are desorbed from the sorbent by acetone. In the following, a dispersive liquid-liquid microextraction procedure is carried out to concentrate the analytes more and to reach low limits of detection.

RESULTS

Under optimized extraction conditions, the method revealed satisfactory repeatability (relative standard deviation ≤8% for intra-day and inter-day precision), reasonable extraction recovery (43.3-55.9%), high enrichment factors (433-559), and low limits of detection (0.45-0.89 μg L^-1 ).

CONCLUSION

The method was applied in the analysis of pesticides in various fruit juices. Chlorpyrifos was found in peach juice at a concentration of 27 ± 2 μg L^-1 (n = 3) using a gas chromatography-flame ionization detector. To verify the results, the peach juice was also injected into gas chromatography-mass spectrometry after applying the proposed extraction method. © 2022 Society of Chemical Industry.

Important Food Sources of Fructose-Containing Sugars and Non-Alcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis of Controlled Trials

Background: Fructose providing excess calories in the form of sugar sweetened beverages (SSBs) increases markers of non-alcoholic fatty liver disease (NAFLD). Whether this effect holds for other important food sources of fructose-containing sugars is unclear. To investigate the role of food source and energy, we conducted a systematic review and meta-analysis of controlled trials of the effect of fructose-containing sugars by food source at different levels of energy control on non-alcoholic fatty liver disease (NAFLD) markers. Methods and Findings: MEDLINE, Embase, and the Cochrane Library were searched through 7 January 2022 for controlled trials ≥7-days. Four trial designs were prespecified: substitution (energy-matched substitution of sugars for other macronutrients); addition (excess energy from sugars added to diets); subtraction (excess energy from sugars subtracted from diets); and ad libitum (energy from sugars freely replaced by other macronutrients). The primary outcome was intrahepatocellular lipid (IHCL). Secondary outcomes were alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Independent reviewers extracted data and assessed risk of bias. The certainty of evidence was assessed using GRADE. We included 51 trials (75 trial comparisons, n = 2059) of 10 food sources (sugar-sweetened beverages (SSBs); sweetened dairy alternative; 100% fruit juice; fruit; dried fruit; mixed fruit sources; sweets and desserts; added nutritive sweetener; honey; and mixed sources (with SSBs)) in predominantly healthy mixed weight or overweight/obese younger adults. Total fructose-containing sugars increased IHCL (standardized mean difference = 1.72 [95% CI, 1.08 to 2.36], p < 0.001) in addition trials and decreased AST in subtraction trials with no effect on any outcome in substitution or ad libitum trials. There was evidence of influence by food source with SSBs increasing IHCL and ALT in addition trials and mixed sources (with SSBs) decreasing AST in subtraction trials. The certainty of evidence was high for the effect on IHCL and moderate for the effect on ALT for SSBs in addition trials, low for the effect on AST for the removal of energy from mixed sources (with SSBs) in subtraction trials, and generally low to moderate for all other comparisons. Conclusions: Energy control and food source appear to mediate the effect of fructose-containing sugars on NAFLD markers. The evidence provides a good indication that the addition of excess energy from SSBs leads to large increases in liver fat and small important increases in ALT while there is less of an indication that the removal of energy from mixed sources (with SSBs) leads to moderate reductions in AST. Varying uncertainty remains for the lack of effect of other important food sources of fructose-containing sugars at different levels of energy control.

Rapid Detection and Quantification of Adulterants in Fruit Juices Using Machine Learning Tools and Spectroscopy Data

Fruit juice production is one of the most important sectors in the beverage industry, and its adulteration by adding cheaper juices is very common. This study presents a methodology based on the combination of machine learning models and near-infrared spectroscopy for the detection and quantification of juice-to-juice adulteration. We evaluated 100% squeezed apple, pineapple, and orange juices, which were adulterated with grape juice at different percentages (5%, 10%, 15%, 20%, 30%, 40%, and 50%). The spectroscopic data have been combined with different machine learning tools to develop predictive models for the control of the juice quality. The use of non-supervised techniques, specifically model-based clustering, revealed a grouping trend of the samples depending on the type of juice. The use of supervised techniques such as random forest and linear discriminant analysis models has allowed for the detection of the adulterated samples with an accuracy of 98% in the test set. In addition, a Boruta algorithm was applied which selected 89 variables as significant for adulterant quantification, and support vector regression achieved a regression coefficient of 0.989 and a root mean squared error of 1.683 in the test set. These results show the suitability of the machine learning tools combined with spectroscopic data as a screening method for the quality control of fruit juices. In addition, a prototype application has been developed to share the models with other users and facilitate the detection and quantification of adulteration in juices.

Rapid analysis of triazine herbicides in fruit juices using evaporation-assisted dispersive liquid-liquid microextraction with solidification of floating organic droplets and HPLC-DAD

A rapid and convenient analytical procedure (evaporation-assisted dispersive liquid-liquid microextraction with solidification of floating organic droplets) is advanced for determining the concentrations of triazine herbicide residues (e.g. simazine and atrazine) in fruit juices via HPLC-DAD. The technique involves adding 1-dodecanol (low density) and dichloromethane (high density) to the test solution to act as the extraction and volatile solvents, respectively. Calcium oxide is added to generate heat to accelerate the evaporation of dichloromethane, whereupon the 1-dodecanol quickly disperses into small droplets to complete the microextraction process. Thus, there is no need to use a dispersive solvent and heating equipment is also not required. The floating 1-dodecanol is subsequently frozen using an ice bath to facilitate its separation from the sample. Under optimal conditions (250 μL of 1-dodecanol (extraction solvent), 150 μL of CH₂Cl₂ (volatile solvent), 1250 mg of CaO, and an extraction time of 60 s) the detection procedure is linear over the range 0.05-5 μg mL^-1 (with R > 0.99). The limits of detection (LOD) and quantification (LOQ) were determined to be 0.0022-0.0034 μg mL^-1 and 0.0073-0.0113 μg mL^-1, respectively. The recovery of simazine and atrazine in three fruit juices ranged between 78.5% and 96.4% with a relative standard deviation <8.2%. Therefore, the proposed approach can be effectively adopted to analyze the triazine herbicide content in fruit juices. The method has been proved to be simple, reliable, and remarkably efficient.

Effect of vitamin D3-fortified fruit juice supplementation of 4000 IU daily on the recovery of iron status in childbearing-aged women with marginally low iron stores: Protocol for an 8-week, parallel group, double-blind randomized controlled trial

Background

In recent years, emerging evidence has highlighted the role of vitamin D as an iron absorption enhancer by suppressing hepcidin concentration, albeit with an unclear underlying mechanism. Dietary-based approach in improving iron status has been widely practised, however, there is a scarcity in randomized controlled trials (RCT) to elucidate the effect of vitamin D-fortified juice on iron status recovery. Therefore, this study aims to investigate the effect of an 8-week vitamin D3-fortified fruit juice supplementation on iron status indicators in childbearing-aged women with marginally low iron stores.

Methods

In a placebo-controlled, double-blind, RCT, a total of 120 women aged between 19–40 with serum ferritin < 20 μg/l and fulfilled the eligibility criteria will be randomized into consuming either vitamin D3-fortified fruit juices containing 4000 IU (100 mcg) (vitamin D) or placebo-fruit juices (placebo) daily for eight weeks. At every 4-week interval, 10 ml fasting blood sample, information on dietary habit and anthropometric measurement will be collected. A mixed model repeated-measures analysis of variance will be performed to determine the effect of the intervention and the interaction with time points for all iron and vitamin D status blood biomarkers.

Discussion

Vitamin D supplementation in food fortification as a novel iron absorption enhancer might be a future and relevant alternative management of iron deficiency as opposed to the oral iron therapy that has poor adherence.

Trial registration

Clinicaltrials.gov: registration number NCT04618289, registration date October 28, 2020, protocol ID JKEUPM-2020-033.

Bioaccessibility of Antioxidants in Blackcurrant Juice after Treatment Using Supercritical Carbon Dioxide

Blackcurrant juice (Ribes nigrum L.) was subjected to supercritical carbon dioxide (SCCD) at 10, 30, and 60 MPa for 10 min at 45 °C, as well as thermally treated at 45 and 85 °C for 10 min to determine the stability, antioxidant capacity (AC), and bioaccessibility (BAc) of vitamin C, total anthocyanins, and their individual monomers. An in vitro gastrointestinal digestion model completed with dialysis was used to assess BAc. The use of SCCD at each of the pressures applied improved the stability of vitamin C, total anthocyanins, and AC before in vitro digestion. As a result of digestion, the total content of vitamin C, anthocyanins, and AC decreased. The highest BAc of vitamin C was noted in fresh juice (FJ) (40%) and after mild heat treatment at 45 °C (T45) (46%). The highest BAc of total anthocyanins was also noted in the FJ (4.4%). The positive effect of the application of SCCD on the BAc of the delphinidin-3-O-glycosides was observed compared to T45 and thermal pasteurization at 85 °C (T85). Although SCCD did not significantly improve the BAc of vitamin C and total anthocyanins, the higher AC of SCCD samples after intestinal digestion (ABTS+• and DPPH•) and in dialysate (ABTS+•) compared to thermally treated was observed. The protocatechuic acid was detected by UPLC-PDA-MS/MS as the major metabolite formed during the digestion of delphinidin-3-O-rutinoside. This may indicate the influence of SCCD on improvement of the accessibility of antioxidants for digestion, thanks to which more metabolites with high antioxidant activity were released.

Fresh pomegranate juices from cultivars and local ecotypes grown in southeastern Italy: comparison of physicochemical properties, antioxidant activity and bioactive compounds

BACKGROUND

Pomegranate juice has gained attention for its health properties, becoming consequently a highly demanded product. The revival of the pomegranate in Italy, as in other Mediterranean countries, starts with the planting of new intensive orchards characterized by both the new cultivation technique and new varieties. As a result of growing demand and high productivity, pomegranate could become an interesting crop to diversify farm income. This study seeks to determine the aril juice quality attributes and bioactive compounds of six pomegranate cultivars ('Mollar', 'Dente di cavallo', 'Acco', 'Jolly red', 'Wonderful' and 'Wonderful Super') and two local ecotypes ('Eco BA' and 'Eco FG') grown in Apulia region, southern Italy.

RESULTS

The aril juices were evaluated for their main physicochemical properties (yield, color, pH, total soluble solids content, titratable acidity, sugar-acid ratio), chemical and bioactive compounds (vitamin C, phenolics, anthocyanins and antioxidant activities). 'Eco BA', 'Mollar' and 'Jolly red' genotypes were characterized by the highest maturity index, and then could be considered to be sweet-sour in taste. Total phenols and antioxidant activity were higher in 'Dente di cavallo' and 'Eco FG' genotypes. 'Eco FG' was also the richest in vitamin C, punicalagin and ellagic acids, while 'Dente di cavallo', 'Acco' and 'Wonderful' showed the highest content of the detected anthocyanin compounds.

CONCLUSION

These results contribute to current knowledge about chemical composition, phenolic contents, anthocyanin profiles and antioxidant activity of pomegranate juice from different genotypes, showing in most cases an appreciable juice quality and bioactive profile, although significant differences among them were detected. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Optical and Electrochemical Aptasensors for Sensitive Detection of Aflatoxin B1 and Aflatoxin M1 in Blood Serum, Grape Juice, and Milk Samples

Aflatoxin food contamination with toxic and carcinogenic impacts on human health is a global concern. We have developed aptasensors for the detection of Aflatoxin M₁ (AFM₁) and B₁ (AFB₁) using electrochemical and optical methods. In the first method, an electrochemical aptasensor was designed for the detection of AFM₁ based on complementary strand of AFM₁ aptamer that was attached onto the gold nanoparticles and a hairpin-shaped AFM₁ aptamer. The designed electrochemical aptasensor showed high selectivity toward AFM₁ with a limit of detection (LOD) as low as 0.9 nM. Moreover, the developed aptasensor was successfully used to detect AFM₁ in milk and serum with LODs of 1.8 and 1.2 nM, respectively. In the second method, a novel electrochemical aptasensor was developed based on the π-shape structure of AFB₁ aptamer. The detection limit was found to be 2 pg/mL in buffer. Also, the developed aptasensor was used to analyze AFB₁ spiked human serum and grape juice samples, and the recoveries were 95.4-108.1%. In another method, a fluorescent sensing scheme was developed for AFB₁ detection based on a hairpin structure of G-quadruplex oligonucleotide-aptamer chimera, streptavidin-coated silica nanoparticles (SNP-streptavidin) and N-methyl mesoporphyrin IX (NMM). The LOD was reported as 8 pg/mL with a linear range of 30-900 pg/mL. Moreover, the developed sensor could detect AFB₁ in serum and grape juice with the LOD of 9.8 and 11.2 pg/mL, respectively.

Phytoprostanes, phytofurans, tocopherols, tocotrienols, carotenoids and free amino acids and biological potential of sea buckthorn juices

BACKGROUND

Juices are currently a fast-growing segment in the fruit and vegetable industry sector. However, there are still no reports on the diversity of the phytochemical profile and health-promoting properties of commercial sea buckthorn (Hippophaë rhamnoides) juices. This study aimed to identify and quantify phytoprostanes, phytofurans by ultra high-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-QqQ-MS/MS), tocopherols, tocotrienols by ultra-performance liquid chromatography coupled with a fluorescence detector (UPLC-FL), carotenoids, and free amino acids by ultra-performance liquid chromatography coupled with a photodiode detector-quadrupole and tandem time-of-flight mass spectrometry (UPLC-PDA-Q/TOF-MS), and assess their anti-cholinergic, anti-diabetic, anti-obesity, anti-inflammatory, and antioxidant potential by in vitro assays of commercial sea buckthorn juices.

RESULTS

Phytoprostanes (PhytoPs) and phytofurans (PhytoFs) in sea buckthorn juices were identified for the first time. Juices contained eight F₁ -, D₁ -, B₁ - and L₁ -phytoprostanes and one phytofuran (32.31-1523.51 ng and up to 101.47 μg/100 g dry weight (DW)), four tocopherol congeners (22.23-94.08 mg 100 g^-1 DW) and three tocotrienols (5.93-25.34 mg 100 g^-1 DW). Eighteen carotenoids were identified, including ten xanthophylls, seven carotenes and phytofluene, at a concentration of 133.65 to 839.89 mg 100 g^-1 DW. Among the 20 amino acids (175.92-1822.60 mg 100 g^-1 DW), asparagine was dominant, and essential and conditionally essential amino acids constituted 11 to 41% of the total. The anti-enzyme and antioxidant potential of juices correlated selectively with the composition.

CONCLUSION

Sea buckthorn juice can be a valuable dietary source of vitamins E and A, oxylipins and amino acids, used in the prevention of metabolic syndrome, inflammation, and neurodegenerative processes. The differentiation of the composition and the bioactive potential of commercial juices indicate that, for the consumer, it should be important to choose juices from the declared berry cultivars and crops. © 2021 Society of Chemical Industry.

Correction of Temperature Variation with Independent Water Samples to Predict Soluble Solids Content of Kiwifruit Juice Using NIR Spectroscopy

Using the framework of aquaphotomics, we have sought to understand the changes within the water structure of kiwifruit juice occurring with changes in temperature. The study focuses on the first (1300-1600 nm) and second (870-1100 nm) overtone regions of the OH stretch of water and examines temperature differences between 20, 25, and 30 °C. Spectral data were collected using a Fourier transform-near-infrared spectrometer with 1 mm and 10 mm transmission cells for measurements in the first and second overtone region, respectively. Water wavelengths affected by temperature variation were identified. Aquagrams (water spectral patterns) highlight slightly different responses in the first and second overtone regions. The influence of increasing temperature on the peak absorbance of the juice was largely a lateral wavelength shift in the first overtone region and a vertical amplitude shift in the second overtone region of water. With the same data set, we investigated the use of external parameter orthogonalisation (EPO) and extended multiple scatter correction (EMSC) pre-processing to assist in building temperature-independent partial least square regression models for predicting soluble solids concentration (SSC) of kiwifruit juice. The interference component selected for correction was the first principal component loading measured using pure water samples taken at the same three temperatures (20, 25, and 30 °C). The results show that the EMSC method reduced SSC prediction bias from 0.77 to 0.1 °Brix in the first overtone region of water. Using the EPO method significantly reduced the prediction bias from 0.51 to 0.04 °Brix, when applying a model made at one temperature (30 °C) to measurements made at another temperature (20 °C) in the second overtone region of water.

Effect of Ultrasound and Enzymatic Mash Treatment on Bioactive Compounds and Antioxidant Capacity of Black, Red and White Currant Juices

Ultrasound treatment is recognized as a potential technique for improvement in the nutritional values of fruit juices. This study was initiated with the objective of evaluating bioactive compounds and some important quality parameters of black (BC), red (RC) and white (WC) currant juices obtained from fruit mash preliminarily treated by enzymes combined with ultrasound. Individual and total phenolic content (TPC), anthocyanins, color parameters, ascorbic acid, antioxidant capacity (TEAC), juice yield, pH, titratable acidity, and soluble solids were investigated. Significant increases in the levels of TPC and antioxidant capacity of sonicated samples were observed. However, ultrasound treatment had no effect on individual phenolic compounds of juices. Sonication of mash before juice pressing did not cause any noticeable changes in ascorbic acid content. Only in the case of WC was an increase in content of vitamin C noticed. The color of juices obtained after treatment was similar to the control sample. It was demonstrated that enzymatic combined with ultrasound treatment of mash for different colored currant fruit did not have any dismissive effect and could even improve some parameters of the juice obtained.

Endothelium-Independent Relaxation of Vascular Smooth Muscle Induced by Persimmon-Derived Polyphenol Phytocomplex in Rats

The vasorelaxant effect of polyphenols is well known, and the mortality rate due to coronary artery disease is low in people who consume polyphenol-containing foods. We aimed to elucidate the mechanism by which polyphenols derived from persimmon juice (PJ) and persimmon leaves (PLs) induce vasorelaxation and suppress vasocontraction in the superior mesenteric arteries isolated from male Sprague Dawley rats. Vasocontraction was induced with 1 µM phenylephrine, and polyphenol-induced vasorelaxation was expressed as a percentage of the previous tone induced by phenylephrine. PJ powder (100 mg/L) induced higher levels of vasorelaxation (mean ± standard error of the mean, 88.6% ± 4.4%) than PLs powder (1 g/L; 72.0% ± 10.8%). Nitric oxide pathway inhibitors (NG-nitro-L-arginine methyl ester + carboxy-PTIO) did not affect persimmon-derived polyphenol-induced vasorelaxation, whereas potassium chloride, tetraethylammonium, and potassium-channel inhibitors did. Vasorelaxation was endothelium independent with both extracts. Phenylephrine-induced vasocontraction was suppressed by pretreatment with PJ and PLs powder, even when inositol triphosphate-mediated Ca²⁺ release and extracellular Ca²⁺ influx were inhibited. These results suggest that persimmon-derived polyphenol phytocomplex cause vasorelaxation and inhibit vasocontraction through hyperpolarization of smooth muscle cells. Persimmon-derived polyphenols may be able to prevent cardiovascular diseases caused by abnormal contraction of blood vessels.