Pulsed electric field technology in vegetable and fruit juice processing: A review.

The worldwide market for vegetable and fruit juices stands as a thriving sector with projected revenues reaching to $81.4 billion by 2024 and an anticipated annual growth rate of 5.27% until 2028. Juices offer a convenient means of consuming bioactive compounds and essential nutrients crucial for human health. However, conventional thermal treatments employed in the juice and beverage industry to inactivate spoilage and pathogenic microorganisms, as well as endogenous enzymes, can lead to the degradation of bioactive compounds and vitamins. In response, non-thermal technologies have emerged as promising alternatives to traditional heat processing, with pulsed electric field (PEF) technology standing out as an innovative and sustainable choice. In this context, this comprehensive review investigated the impact of PEF on the microbiological, physicochemical, functional, nutritional, and sensory qualities of vegetable and fruit juices. PEF induces electroporation phenomena in cell membranes, resulting in reversible or irreversible changes. Consequently, a detailed examination of the effects of PEF process variables on juice properties is essential. Monitoring factors such as electric field strength, frequency, pulse width, total treatment time, and specific energy is important to ensure the production of a safe and chemically/kinetically stable product. PEF technology proves effective in microbial and enzymatic inactivation within vegetable and fruit juices, mitigating factors contributing to deterioration while maintaining the physicochemical characteristics of these products. Furthermore, PEF treatment does not compromise the content of substances with functional, nutritional, and sensory properties, such as phenolic compounds and vitamins. When compared to alternative processing methods, such as mild thermal treatments and other non-thermal technologies, PEF treatment consistently demonstrates comparable outcomes in terms of physicochemical attributes, functional properties, nutritional quality, and overall safety.

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.

A Single Dose of Beetroot Juice not Enhance Performance during Intervallic Swimming Efforts.

Despite the numerous scientific evidence on the topic, there is no clear and consistent answer that clarifies the true effects of beetroot juice (BJ) supplementation on different types of physical performance. This study examined whether an acute intake of BJ improves swimming performance, physiological variables of anaerobic metabolism, or subjective measures during high-intensity interval exercise with incomplete rest in competitive swimmers. Eighteen competitive swimmers (nine females and nine males) participated in this cross-over randomized, placebo-controlled, double-blind and counterbalanced study. In two trials, swimmers ingested BJ (70 mL, 6.4 mmol/400 mg NO3-) or placebo (PLA) (70 mL, 0.04 mmol/3 mg NO3-) three hours before a 2×6×100 m maximal effort with 40 seconds rest between repetitions and three minutes between blocks. The 100 m times showed no differences between groups (p > 0.05), but there was an interaction between block×repetition×condition (F5 = 3.10; p = 0.046; ηp2 = 0.54), indicating that the BJ group decreased the time of the sixth repetition of block2 compared to block1 (p = 0.01). Lactate concentration showed no differences between conditions (p > 0.05), but there was a main effect of block (ηp2 = 0.60) and a block×repetition interaction (ηp2 = 0.70), indicating higher values in block2 and increasing values between repetitions in block1. The subjective scales, perception of exertion (RPE) and Total Quality Recovery (TQR), showed no effects of condition (p > 0.05), but BJ swimmers had a greater TQR in the last repetitions of each block. In conclusion, a single dose of BJ did not enhance intermittent swimming performance or modified the physiological (lactate and heart rate) or subjective (RPE and TQR) variables; although there was a possible positive effect on the exercise tolerance at the end of effort.

Pyrococcus furiosus argonaute based Alicyclobacillus acidoterrestrsis detection in fruit juice.

Alicyclobacillus acidoterrestris is the major threat to fruit juice for its off-odor producing characteristic. In this study, Pyrococcus furiosus Argonaute (PfAgo), a novel endonuclease with precise DNA cleavage activity, was used for A. acidoterrestrisdetection, termed as PAD. The partially amplified 16 S rRNA gene of A. acidoterrestris can be cleaved by PfAgo activated by a short 5'-phosphorylated single strand DNA, producing a new guide DNA (gDNA). Then, PfAgo was activated by the new gDNA to cut a molecular beacon (MB) with fluorophore-quencher reporter, resulting in the recovery of fluorescence. The fluorescent intensity is positively related with the concentration of A. acidoterrestris. The PAD assay showed excellent specificity and sensitivity as low as 101 CFU/mL, which can be a powerful tool for on-site detection of A. acidoterrestris in fruit juice industry in the future, reducing the economic loss.

Warning labels for sugar-sweetened beverages and fruit juice: evaluation of 27 different labels on health effects, sugar content, energy and exercise equivalency.

OBJECTIVES: Front-of-pack warning labels may reduce consumption of sugar-sweetened beverages, potentially mitigating negative health outcomes. Comparisons between different warning label types to inform future research and policy directions are lacking. This study compared 27 warning labels across six message types for their potential to reduce sugar-sweetened beverage consumption. DESIGN AND METHODS: A national sample of regular soda (n = 2578) and juice (n = 1048) consumers aged 14-60 years participated in an online survey. Participants evaluated randomly allocated labels; one from each of six warning label sets (health-graphic, sugar-pictogram, sugar-text, exercise equivalents, health-text, energy information) on four measures of perceived effectiveness (PE: overall effectiveness, discourage from drinking, emotional response, persuasive potential). Participants could also provide open comments. A general linear model compared differences in mean scores across label sets for each measure of PE. RESULTS: PE ratings differed significantly between label sets. Labels clearly quantifying sugar content (sugar-teaspoons) received consistently high PE ratings, whereas 'high in sugar' labels did not. Health-graphic labels were rated highly across all PE measures except persuasive potential. Exercise labels only rated highly on persuasive potential. Health-text results were mixed, and energy labels were consistently low. CONCLUSIONS: Simple, factual labels were easily interpreted and perceived as most effective. Labels quantifying sugar content were consistently high performers and should be advanced into policy to help decrease overconsumption of sugar-sweetened beverages.

Modulation of the gut microbiota and short-chain fatty acid production by gac fruit juice and its fermentation in in vitro colonic fermentation.

This study aimed to investigate the effects of gac fruit juice and its probiotic fermentation (FGJ) utilizing Lactobacillus paracasei on the modulation of the gut microbiota and the production of short-chain fatty acids (SCFAs). We conducted a comparison between FGJ, non-fermented gac juice (GJ), and control samples through in vitro digestion and colonic fermentation using the human gut microbiota derived from fecal inoculum. Our findings revealed that both GJ and FGJ led to an increase in the viability of Lactobacilli, with FGJ exhibiting even higher levels compared to the control. The results from the 16S rDNA amplicon sequencing technique showed that both GJ and FGJ exerted positive impact on the gut microbiota by promoting beneficial bacteria, notably Lactobacillus mucosae and Bacteroides vulgatus. Additionally, both GJ and FGJ significantly elevated the levels of SCFAs, particularly acetic, propionic, and n-butyric acids, as well as lactic acid, in comparison to the control. Notably, FGJ exhibited a more pronounced effect on the gut microbiota compared to GJ. This was evident in its ability to enhance species richness, reduce the Firmicutes to Bacteroidetes (F/B) ratio, promote Akkermansia, and inhibit pathogenic Escherichia coli. Moreover, FGJ displayed enhanced production of SCFAs, especially acetic and lactic acids, in contrast to GJ. Our findings suggest that the probiotic fermentation of gac fruit enhances its functional attributes in promoting a balanced gut microbiota. This beverage demonstrates potential as a functional food with potential advantages for sustaining intestinal health.

Development of a processing factor prediction model for pesticides in processed tomato foods using elastic net regularization.

A novel regularized elastic net regression model was developed to predict processing factor (PF) for pesticide residues, which represents a change in the residue levels during food processing. The PF values for tomato juice, wet pomace and dry pomace in the evaluations and reports published by the Joint FAO/WHO Meeting on Pesticide Residues significantly correlated with the physicochemical properties of pesticides, and subsequently the correlation was observed in the present tomato processing study. The elastic net regression model predicted the PF values using the physicochemical properties as predictor variables for both training and test data within a 2-fold range for 80-100% of the pesticides tested in the tomato processing study while overcoming multicollinearity. These results suggest that the PF values are predictable at a certain degree of accuracy from the unique sets of physicochemical properties of pesticides using the developed model based on a processing study with representative pesticides.

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.

Nano­selenium functionalized chitosan gel beads for Hg(II) removal from apple juice.

The presence of potentially toxic elements and compounds poses threats to the quality and safety of fruit juices. Among these, Hg(II) is considered as one of the most poisonous heavy metals to human health. Traditional chitosan-based and selenide-based adsorbents face challenges such as poor adsorption capacity and inconvenient separation in juice applications. In this study, we prepared nano­selenium functionalized chitosan gel beads (nanoSe@CBs) and illustrated the synergistic promotions between chitosan and nanoSe in removing Hg(II) from apple juice. The preparation conditions, adsorption behaviors, and adsorption mechanism of nanoSe@CBs were systematically investigated. The results revealed that the adsorption process was primarily controlled by chemical adsorption. At the 0.1 % dosage, the adsorbent exhibited high uptake, and the maximum adsorption capacity from the Langmuir isotherm model could reach 376.5 mg/g at room temperature. The adsorbent maintained high adsorption efficiency (> 90 %) across a wide range of Hg(II) concentrations (0.01 to 10 mg/L) and was unaffected by organic acids present in apple juice. Additionally, nanoSe@CBs showed negligible effects on the quality of apple juice. Overall, nanoSe@CBs open up possibilities to be used as a safe, low-cost and highly-efficient adsorbent for the removal of Hg(II) from juices and other liquid foods.

A consumer evaluation of salt-reduced tomato soup and vegetable juice made with grape pomace.

Obesity and obesity-related illness have become an increasingly prevalent problem and there is a critical need to combat this by reducing sugar, salt, and fat consumption. Due to this concern, the food industry has been developing salt-reduced foods, however, these products need to maintain their sensory appeal and flavors, which has proven to be a challenge. Grape pomace (GP), the solids left after pressing grapes for winemaking and consisting of grape seeds and skins, has been proposed as an environmentally friendly solution that can enhance the acceptability of salt-reduced food products. However, GP is associated with a large number of flavor compounds. As such, the objective of this research is to investigate the acceptability of GP addition in salt-reduced foods. Two trials were conducted using hedonic scales and temporal check-all-that-apply (TCATA) to evaluate tomato soup (n = 88) and vegetable juice (n = 99). Each trial included a control and sample containing grape pomace. The addition of the GP decreased the consumers' overall liking and the liking of the flavor, as well as increasing consumers' perception of saltiness intensity. The samples made with GP were associated with bitterness, sourness, and wine flavor during the TCATA evaluations. The study identified that GP increased saltiness perception, however, it also adds other flavors to the food product, which decreased the acceptability of the food items. PRACTICAL APPLICATION: There is a consumer demand to create salt-reduced foods that do not have altered sensory properties. Furthermore, consumers are interested in sustainable and environmentally friendly ingredients. Grape pomace is a byproduct of the wine industry and has been proposed as an ingredient that can increase the saltiness perception of food products. Grape pomace was added to tomato soup and vegetable juice to evaluate its effect on consumer acceptability and saltiness perception. The grape pomace did increase saltiness perception, but also added bitterness, sourness, and wine flavor to the food products.

Development of microencapsulated grape juice powders using black 'Isabel' grape peel pectin and application in jelly formulation with enhanced in vitro bioaccessibility of anthocyanins.

In this study, pigmented pectin (grape pectin, GP) was extracted from the peels of black Isabel grapes. This highly methoxylated GP was composed mainly of galacturonic acid, arabinose, and other neutral monosaccharides. Its red color was ascribed to the anthocyanin content, and the main contribution was from malvidin-3-O-glucoside. To improve the yield and color properties of spray-dried Isabel grape juice powders, maltodextrin (MD) was substituted with this colored GP. When 25% of MD was substituted with GP, the powder yield increased from 46.0% to 60.4%, but it decreased to 21% when the substitution was 40%. GP inclusion increased the encapsulation efficiency of total anthocyanin in powders from 55.70% to 88.66%. When this spray-dried grape juice powder containing GP was utilized in a jelly recipe (4%-10%), a higher level of inclusion yielded stronger and more brittle jellies. When the jellies containing varying amounts of GP were subjected to in vitro digestion, the formulation with a higher amount of GP yielded a higher recovery of anthocyanins. In addition to being utilized as a carrier agent for spray-drying applications, this pigmented GP can also be tailored for a variety of applications, such as the development of pH-sensitive edible films and functional beverage formulations.

Food and environmental safety monitoring platform based on Tb(III) functionalized HOF hybrids for ultrafast detection of thiabendazole and 2-chlorophenol.

Development of efficient and intelligent method for detecting harmful agrochemicals in resource-limited settings remains an urgent need to ensure food and environmental safety. Herein, a novel dual-emitting Tb3+-modified hydrogen-bonded organic framework (Tb@TBTC, TBTC is the ligand of HOF-TBTC.) with visible green fluorescence has been prepared through coordination post-synthetic modification. Tb@TBTC can be designed as a fluorescence sensor for the identification of two harmful carcinogenic pesticides, thiabendazole (TBZ) and 2-chlorophenol (2-CP) with high sensitivity, high efficiency and excellent selectivity. Tb@TBTC can also adsorb 2-CP with high adsorption rate. In realistic fruit juice and river water samples, the detection limits of Tb@TBTC toward TBZ and 2-CP are as low as 2.73 µM and 2.18 µM, respectively, demonstrating the feasibility in practical application. Furthermore, an intelligent real-time and on-site monitoring platform for 2-CP detection is constructed based on Tb@TBTC-agarose hydrogel films with the assistance of back propagation neural network, which can efficiently and accurately determine the concentration of 2-CP from fluorescence images through human-machine interaction. This work presents a facile pathway to prepare Tb@HOF fluorescent sensor for food and ecological environment safety, which is highly promising for preventing human disease and improving global public health.

Efecto del zumo del fruto Solanum quitoense (lulo) sobre el daño cerebral y cognitivo inducido por cloruro de mercurio en ratones / Effect of Solanum quitoense (lulo) fruit juice on brain and cognitive damageinduced by mercury chloride in mice

Introducción: Las enfermedades neurodegenerativas han ido en aumento durante las últimas décadas, siendo la demencia la principal patología con mayor repercusión a nivel global. Objetivo: Evaluar el efecto neuroprotector del zumo del fruto Solanum quitoense (lulo) frente a la toxicidad del cloruro de mercurio (II) en los ratones. Materiales y métodos: Diseño experimental, con grupo control y posprueba. Se empleó 42 ratones machos. Para inducir a la toxicidad se empleó una solución de HgCl2 (10 mg/kg), vía orogástrica, por un periodo de siete días. Durante ese periodo recibieron los siguientes tratamientos: grupos I y II suero fisiológico; grupos III vitamina E (40UI/kg); grupo IV-V-VI zumo de lulo, 0,5; 2,0 y 8,0 mL/kg, respectivamente. Terminado el tratamiento los animales fueron sacrificados por decapitación, el cerebro y cerebelo fueron extraído de la cavidad craneana. El hemisferio izquierdo fue homogenizado para la determinación de la lipoperoxidación, glutatión (reducido y total), actividad de superóxido dismutasa y catalasa. El hemisferio derecho y cerebelo fueron conservados, para la evaluación histológica. Se evaluó la función cognitiva (aprendizaje y memoria), según protocolo de Deacon y Rawlis. Resultados: La administración del zumo de lulo disminuyeron los índices de cerebro en los grupos V-VI. La lipoperoxidación disminuyó (grupos IV-VI), la relación GSH/GSSG aumentaron (grupos V-VI). La actividad de la catalasa aumentó (grupos IV-VI). La relación SOD/CAT disminuyeron (grupos IV-VI). El tiempo de latencia y número de intentos fueron menores en los grupos IV-VI. Conclusiones: La administración del zumo del fruto Solanum quitoense presenta efecto neuroprotector para el modelo estudiado. Palabras clave: Neuroprotección, Solanum quitoense, cloruro de mercurio, función cognitiva, alimento funcional (Fuente: DeCS BIREME).(AU)

Introduction: Neurodegenerative diseases have beenincreasing in recent decades, with dementia being the mainpathology with the greatest impact globally. Objective: To evaluate the neuroprotective effect ofSolanum quitoense (lulo) fruit juice against the toxicity ofmercury (II) chloride in mice. Materials and methods: Experimental design, withcontrol group and post-test. 42 male mice were used. Toinduce toxicity, a solution of HgCl2 (10 mg/kg) was used viathe orogastric route for a period of seven days. During thisperiod, they received the following treatments: groups I and II physiological saline; groups III vitamin E (40IU/kg); groupIV-V-VI lulo juice, 0.5; 2.0 and 8.0 mL/kg, respectively. Oncethe treatment was completed, the animals were sacrificed bydecapitation, the brain and cerebellum were removed fromthe cranial cavity. The left hemisphere was homogenized forthe determination of lipoperoxidation, glutathione (reducedand total), superoxide dismutase and catalase activity. Theright hemisphere and cerebellum were preserved forhistological evaluation. Cognitive function (learning andmemory) was evaluated according to the Deacon and Rawlisprotocol. Results: The administration of lulo juice decreased brainindices in groups V-VI. Lipoperoxidation decreased (groupsIV-VI), the GSH/GSSG ratio increased (groups V-VI). Catalaseactivity increased (groups IV-VI). The SOD/CAT ratiodecreased (groups IV-VI). The latency time and number ofattempts were lower in groups IV-VI. Conclusions: The administration of Solanum quitoensefruit juice has a neuroprotective effect for the model studied.(AU)

Antibacterial effects of various molecular weight chitosans against Alicyclobacillus acidoterrestris in orange juice.

Alicyclobacillus acidoterrestris has been gaining attention due to its unique thermo-acidophilic properties and being associated with the deterioration of pasteurized beverages. The objective of this study was to evaluate the antibacterial activity of chitosan with various molecular weights (MWs) (164, 85, 29.2, and 7.1 kDa) and concentrations (0-100 µg/mL) against A. acidoterrestris and its effect on guaiacol production. Various chitosan MWs were co-incubated for 7 days, and the bacterial growth, guaiacol, and vanillic acid contents during storage were determined. The chitosans performed antibacterial effects against A. acidoterrestris. Further, 164 kDa chitosan showed excellent results in controlling the growth and guaiacol formation in A. acidoterrestris. These findings demonstrated the efficacy of chitosan antibacterial activity against A. acidoterrestris and mitigating the guaiacol formation. Chitosan's antibacterial properties are attributed to the elimination of cells and suppression of guaiacol production. This study introduces a new approach for reducing A. acidoterrestris contamination in fruit juices, with potential product quality and safety advantages.

Bimetallic AuNR@AgNCs for ultrasensitive surface-enhanced Raman scattering sensing of dithianon in apple juice.

In this study, a bimetallic surfaced-enhanced Raman spectroscopy (SERS)-active substrate consisting of AuNR@AgNCs was proposed for the rapid detection of dithianon. Due to the significant synergistic enhancement of the core-shell nanocuboids, the obtained AuNR@AgNC substrate exhibited excellent SERS performance. The simulation findings supported the practical SERS results and demonstrated that interactions were mainly maintained by the nitrile functional group. The AuNR@AgNCs could be used to detect dithianon with an LOD value of 20 nM. Moreover, dithianon in river water and apple juice could be detected with recovery in the satisfactory ranges of 97.41%-98.35% and 97.77%-98.70%, respectively, by using this substrate under optimal conditions, indicating that the AuNR@AgNC substrate could serve as an excellent SERS detection platform for pesticide residues in fruit.

Regulating the defects of MIL-101(Cr) for the efficient and simultaneous determination of eleven plant growth regulators in fresh fruit juice.

This work presents an efficient sorbent for plant growth regulators (PGRs) by regulating the defects of a metal-organic framework MIL-101(Cr). Using the regulated MIL-101(Cr), we developed a simple and effective method for the simultaneous determination of eleven PGRs in fresh fruit juice. The extraction conditions were optimized by an orthogonal array design. Under optimal conditions, the method showed a satisfactory limit of detection (0.1-1.2 ng/g), recovery rates (83.4-110.2 %), and precision (2.9-18.0 % for intra-day and 2.7-10.8 % for inter-day), as well as a greatly suppressed matrix effect. Notably, regulating the defects significantly enhanced the desorption of PGRs on MIL-101(Cr). The sorbent didn't need to be destroyed to release the adsorbed PGRs and could be reused at least 6 times. Furthermore, the defects of MIL-101(Cr) and interactions between the sorbent and PGRs were studied by TGA, ATR-IR, XPS, NH3-TPD and UV-Vis DRS.

Prevalence, antimicrobial susceptibility test and associated factors of Salmonella and Shigella in ready-to-eat fruit juices and salads in Mekelle, northern Ethiopia.

BACKGROUND: Food borne diseases is a challenging problem nowadays. Salmonella and Shigella species are great concern of food-born outbreaks. Thus, this study was aimed to assess the prevalence, antimicrobial susceptibility test and associated factors of Salmonella and Shigella species in fruit juices and salads. METHODS: A community based cross sectional study design was carried out on 50 juice houses from December to March 2020 in Mekelle. One hundred fifty samples were collected aseptically from the juice houses for laboratory analysis. Information related to risk factors was obtained using a structured questionnaire. In the laboratory, samples were homogenized using peptone water and incubated overnight for enrichment. Then, Salmonella and Shigella species were isolated on Salmonella-Shigella agar and Xylose Lysine Deoxycholate agar. Disc diffusion method was used to perform antimicrobial susceptibility test. Using SPSS (version 22) package, descriptive statistics and Chi square test (χ2) were used to analyze the data, and p < 0.05 was considered as statistically significant. RESULT: The overall prevalence of Salmonella and Shigella species was 41/150 (27.33%; 95% CI: 20.20 - 34.46) with 33 (22%) Salmonella spp. and 8(5.33%) Shigella spp. Antimicrobial susceptibility tests of both Salmonella and Shigella spp.showed high resistance against ampicillin (100%), tetracycline (63.6 and 62.5%, respectively) and amoxicillin-clavulanic acid (100%). Accessibility of fruits to flies and dust had statistical association (p = 0.021) with occurrence of Salmonell a and/or Shigella spp. CONCLUSION: The overall prevalence of Salmonella and Shigella spp. was found to be significant. The resistant rate of isolates against ampicillin, tetracycline and amoxicillin-clavulanic acid was high. Storage sites for fruits should be inaccessible to flies and dust. Therefore, routine monitoring of juice houses should be promoted and regular evaluation of bacterial resistance pattern should be done for selective antimicrobial therapy. Furthermore, consistent training of juice makers on food safety and hygiene should be implemented by the concerned body.

Method for Glucose and Fructose Quantitation in Beverages Using an Off-the-Shelf Glucose Test Strip.

A method was developed for quantifying both glucose and fructose in solutions and grape juice using commercially available glucose test strips connected to a mini-potentiostat. The first step of this sensing approach involved exposing the sample solution to an Accu Chek Aviva glucose test strip, which allowed for the direct quantitation of glucose. To quantify fructose, the solution was exposed to glucose isomerase, which led to the conversion of glucose to fructose and vice versa until an equilibrium was reached. Once equilibrium was reached, the solution was exposed to another glucose test strip; the signal obtained was shown to be related to the total amounts of glucose and fructose in solution. Finally, fructose was quantified by subtracting the glucose concentration (from the initial measurement) from the total concentration of glucose and fructose (from the second measurement after the reaction with glucose isomerase). The method yielded a limit of detection of 0.047 g L-1 for glucose and 0.49 g L-1 for fructose. Importantly, this method was shown to work well for analyzing glucose and fructose concentration in grape juice, which contains >60 g L-1 glucose and fructose. Since the ratio of glucose and fructose concentration in ripe grapes is close to 1, this method can be used to aid in the determination of grape ripeness to guide harvesting times.

Consumption of 100% Fruit Juice and Body Weight in Children and Adults: A Systematic Review and Meta-Analysis.

Importance: Concerns have been raised that frequent consumption of 100% fruit juice may promote weight gain. Current evidence on fruit juice and weight gain has yielded mixed findings from both observational studies and clinical trials. Objective: To synthesize the available evidence on 100% fruit juice consumption and body weight in children and adults. Data Sources: MEDLINE, Embase, and Cochrane databases were searched through May 18, 2023. Study Selection: Prospective cohort studies of at least 6 months and randomized clinical trials (RCTs) of at least 2 weeks assessing the association of 100% fruit juice with body weight change in children and adults were included. In the trials, fruit juices were compared with noncaloric controls. Data Extraction and Synthesis: Data were pooled using random-effects models and presented as ß coefficients with 95% CIs for cohort studies and mean differences (MDs) with 95% CIs for RCTs. Main Outcomes and Measures: Change in body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) was assessed in children and change in body weight in adults. Results: A total of 42 eligible studies were included in this analysis, including 17 among children (17 cohorts; 0 RCTs; 45 851 children; median [IQR] age, 8 [1-15] years) and 25 among adults (6 cohorts; 19 RCTs; 268 095 adults; median [IQR] age among cohort studies, 48 [41-61] years; median [IQR] age among RCTs, 42 [25-59]). Among cohort studies in children, each additional serving per day of 100% fruit juice was associated with a 0.03 (95% CI, 0.01-0.05) higher BMI change. Among cohort studies in adults, studies that did not adjust for energy showed greater body weight gain (0.21 kg; 95% CI, 0.15-0.27 kg) than studies that did adjust for energy intake (-0.08 kg; 95% CI, -0.11 to -0.05 kg; P for meta-regression <.001). RCTs in adults found no significant association of assignment to 100% fruit juice with body weight but the CI was wide (MD, -0.53 kg; 95% CI, -1.55 to 0.48 kg). Conclusion and Relevance: Based on the available evidence from prospective cohort studies, in this systematic review and meta-analysis, 1 serving per day of 100% fruit juice was associated with BMI gain among children. Findings in adults found a significant association among studies unadjusted for total energy, suggesting potential mediation by calories. Further trials of 100% fruit juice and body weight are desirable. Our findings support guidance to limit consumption of fruit juice to prevent intake of excess calories and weight gain.