Fresh Orange Juice Research Articles

Amperometric Determination of Dopamine and Ascorbic Acid with a Carbon Paste‐Yttrium Oxide Electrode

AbstractThis report presents a new application for yttrium oxide (YOX) in the modification of carbon paste electrodes with excellent electroactivity for the independent detection of dopamine (DA) and ascorbic acid (AA). The surface of the YOX‐modified electrode was characterized with SEM and EDS. The electroactive properties of DP and AA were studied with cyclic voltammetry (CV), square wave voltammetry (SWV) and amperometry (Am). The activity of DA and AA increased by more than 100 % when YOX/CPE was used, which allowed us to obtain detection limits of 0.04 and 0.06 μmol/L for DA and AA, respectively. The usefulness of YOX/CPE was tested with real human urine, fresh orange juice and vitamin C tablets, and the results were acceptable.

Microencapsulation of tomato oleoresin using tomato waste fibre and its application for orange juice fortification

SummaryFood waste by‐products contain many bioactive compounds, such as proteins, carbohydrates, polyphenols and carotenoids. The purposes of this study was to extract oleoresin from tomato waste, apply tomato pomace powder (TPP) as a new shell material for encapsulation of oleoresin and to fortify orange juice using the developed microcapsules. Microencapsulation was carried out based on different TPP (2% and 3%) and oleoresin (20% and 30%) concentrations by spray drying at two temperatures (130 and 140 °C). Different features of microcapsules such as the encapsulation load, encapsulation efficiency, moisture content, hygroscopicity, bulk and tapped densities and the Hausner ratio were analysed. Based on properties of microcapsules, samples containing 3% TPP and 30% oleoresin dried at 130 °C were selected as the best treatment and their characteristics such as morphology, chemical structure and thermal behaviour were investigated. Scanning electron microscopy indicated that spherical micron‐size particles were formed and their crack‐free fine surface showed their potential for encapsulation of anti‐oxidants to reduce oxygen diffusion. Microencapsulated oleoresin was then added to the orange juice and the samples' pH, acidity, total soluble solids and colour were evaluated and compared with pure orange juice. Free radical scavenging method was used to investigate the anti‐oxidant properties of orange juice during storage. The results indicated that at the end of the 30 days of storage the fortified orange juice had anti‐oxidant activity equal to pure fresh orange juice on day one. Sensory evaluation results showed no significant differences between appearance, colour, thickness and overall acceptance of fresh and the fortified juices (P < 0.05). The results of this study showed the potential application of food and agricultural waste in production of value‐added ingredients to be used as natural additives in food industries.

Enhancing Quality Properties of Fresh Orange Juice through the Addition of Freeze-Dried Cassia javanica Extracts’ Coacervates

This study investigated the impact of freeze-dried coacervates at various concentrations (0.5, 1, and 1.5%) on physicochemical and microbiological properties of orange juice. Either 60% ethanol freeze-dried coacervates (EFC) or absolute ethanol freeze-dried coacervates (AFC) were used. The addition of EFC or AFC to orange juice did not significantly (p<0.05) affect pH, viscosity, or electric conductivity, as pH was unchanged for a 0.5% concentration and slightly increased from 3.99 to 4.01 at 1% and 1.5% concentrations. After adding AFC and EFC, viscosity were 52, 53, and 53 mPas at 0.5, 1, and 1.5% concentrations, respectively. Electric conductivity increased from 0.278 s.m-1 (control) to 0.334, 0.347, and 0.375 s.m-1 at 0.5, 1, and 1.5% concentrations after adding EFC, while were 0.325, 0.335, and 0.373 s.m-1 at the same concentration after adding AFC, respectively. However, after adding EFC, total phenolic content increased to 77.25, 115.96, and 154.95 mg.100mL-1, total flavonoid content (TFC)increased to 34.76, 52.18, and 69.73 mg.100mL-1, and antioxidant activity (AA) enhanced to 70.36, 74.36, and 79.58% at concentrations 0.5, 1, and 1.5%, respectively. Also, after adding AFC, total phenolic content increased to 79.26, 117.78, and 156.25 mg.100mL-1, TFC increased to 35.67, 53.00, and 70.31 mg.100mL-1, and AA enhanced to 71.65, 75.84, and 81.21% at concentrations 0.5, 1, and 1.5%, respectively. At concentrations 0.5, 1, and 1.5%, EFC decreased total plate count (TPC) to 2.12, 2.02, and 1.78 log cfu.mL-1, respectively and mold and yeast counts decreased to 1.5, 1.35, and 1.1 log cfu.mL-1, respectively. Also, adding AFC caused TPC to decrease to 2.18, 2.04, and 1.84 log cfu.mL-1, respectively and mold and yeast count decreased to 1.53, 1.33, and 1.12 log cfu.mL-1, respectively. Overall, the results indicate that adding EFC or AFC to fresh orange juice can enhance its nutritional and microbiological qualities without degrading its sensory qualities.

Enhanced antibacterial activity of bovine milk exosome-based drug formulation against bacterial pathogens

Milk is not only a source of nutrients, but also contains exosomes (Exo) that can serve as a vehicle for drug delivery. Here, we obtained bovine milk Exo using three efficient methods, demonstrating high quality for commercial production. The optimized Exo displayed a size of 105.2 nm and an entrapment efficiency of 88.4 %. The Exo has been functionalized with a combination therapy comprising isobavachalcone (IS) and polymyxin B (PB), referred to as IP-Exo. The antibacterial efficacy of IP-Exo was significantly enhanced, enabling the elimination of 99 % of multidrug-resistant (MDR) bacterial pathogens in 4 h. Furthermore, scanning electron microscopy images demonstrated that the drug combination led to the complete dismantling of the bacterial structure. IP-Exo showed nearly 100 % microbial inhibition in fresh orange juice and accelerated wound healing in mouse models. Collectively, IP-Exo provides excellent potential for application within the food industry and animal husbandry as a defense against bacterial pathogens.

Exploring hydrodynamic cavitation for citrus waste valorisation in Malta: from beverage enhancement to potato sprouting suppression and water remediation.

Introduction: The endorsement of circular economy, zero-waste, and sustainable development by the EU and UN has promoted non-thermal technologies in agro-food and health industries. While northern European countries rapidly integrate these technologies, their implementation in Mediterranean food-supply chains remains uncertain. Aims: We evaluated the usefulness of hydrodynamic cavitation (HC) for valorizing orange peel waste in the fresh orange juice supply chain of the Maltese Islands. Method: We assessed: a) the effectiveness of HC in extracting bioactive compounds from orange peels (Citrus sinensis) in water (35°C) and 70% (v/v) ethanol (-10°C) over time, compared to conventional maceration, and b) the potato sprouting-suppression and biosorbent potential of the processed peel for copper, nitrate, and nitrite binding. Results: Prolonged HC-assisted extractions in water (high cavitation numbers), damaged and/or oxidized bioactive compounds, with flavonoids and ascorbic acid being more sensitive, whereas cold ethanolic extractions preserved the compounds involved in radical scavenging. HC-processing adequately modified the peel, enabling its use as a potato suppressant and biosorbent for copper, nitrate, and nitrite. Conclusion: Coupling HC-assisted bioactive compound extractions with using leftover peel for potato-sprouting prevention and as biosorbent for water pollutant removal offers a straightforward approach to promoting circular economic practices and sustainable agriculture in Malta.

Design and manufacture of a device for pasteurizing orange juice and its effects on the qualitative characteristics of fresh orange juice

The research project was conducted on the Batch Ohmic Heater, which was designed and manufactured in the laboratories of the Department of Food Sciences/College of Agriculture and Forestry/University of Mosul, to be used in sterilization of orange juice. The study included the effect of Ohmic heating at voltages of 80, 110 and 220 volts on the chemical, physical and sensory properties and compared them with samples of orange juice treated by the conventional heating method (95 Cº/15 s). Ohmic heating with the applied voltage gradients (9.2, 12.64 and 25.28 V/cm) significantly (p≤0.05) preserved the total phenols content of the orange juice samples compared with the samples treated with conventional heating immediately after treatment, however, voltage gradient ( 12.64) acquired significantly (p≤0.05) higher in average total soluble solids (TSS) over other treatments for average refrigeration period (14 days) Using a voltage gradient of 12.64 V/cm for orange juice samples showed a significant decrease (p≤0.05) in the pH values compared with the other used voltage gradients. There was the highest significant increase (p≤0.05) in the concentration of vitamin C for orange juice samples treated by Ohmic heating at voltage gradient 9.2 V/cm compared with the other samples. In the study of sensory evaluation of orange juice treated by Ohmic heating at a voltage of 12.64 V/cm, which obtained the highest degree of sensory evaluation with two grades of excellent and very good within the evaluation scores used for that (1 unacceptable - 8 excellent) by the arbitrators compared with the rest of the orange juice samples.

Ultrathin porous PdCu metallenezymes as oxidase mimics for colorimetric analysis.

Ultrathin porous and highly curved two-dimensional PdCu alloy metalleneare shown to be highly efficient oxidase mimics. Serving as intrinsic oxidase mimic, the ultrathin porous structure of the PdCu metallenezymes could effectively utilize all the Pd atoms of the metallenezymes during catalytic reactions. By using the oxidation capability of 3,3'5,5'-tetramethylbenzidine as distinctive chromogenic substrate, the PdCu metallenezymes was used as oxidase-like mimics for determination of total antioxidant capacity (TAC) of vitamin C containing real products including fresh orange juice, commercial beverages, Vitamin C tablets and dermo-cosmetic products. AAP was hydrolyzed using ALP to generate AA and the corresponding ALP activity was successfully detected in the0-100 U/L rangewith a lowest detection limit of 0.9 U/L. This study demonstrates the significant catalytic performance and oxidase-like activity of PdCu metallene nanozyme providing astrategy to develop a TAC assay for the assessment of antioxidant food quality as well as oxidative stress in skin and health care products.

Antimicrobial and Antioxidant Activities of Lemongrass Oil (Cymbopogon citratus), in Preservation of Fresh Orange Juice

Antimicrobial and Antioxidant Activities of Lemongrass Oil (Cymbopogon citratus), in Preservation of Fresh Orange Juice

A comparative study of drinking straws made from natural resources: structural and morphological characterization

This study focuses on identifying a high-value material using low-cost raw resources by comparing wheat straw varieties collected in Greece with other commercial straws made of reed, bamboo, paper, and bioplastic. The structural characteristics, water absorption behavior, and morphological properties of the straws were analyzed using X-ray diffraction, water immersion tests, and scanning electron microscopy. The thermal degradation was investigated using thermogravimetric analysis. The results suggest that the wheat straws exhibit a significant degree of crystallinity, with the Staramaki K1 straw exhibiting the highest crystallinity of all the straws analyzed. The mass of wheat straws increased after immersion in water, coca-cola, and fresh orange juice in contrast to the mass of bioplastic and bamboo straws, which remained constant. The surface examination revealed modifications to the strawsʼ outer and inner surfaces after immersion in the various solutions. To variable degrees, pores, cracks, peeling material, lighter patches, and anomalies were seen. The presence of a highly crystalline structure can increase the strawʼs hardness and reduce its water absorption, making it more resistant to changes brought about by the solutions. So, the Staramaki K1 wheat straw exhibits favorable properties, including high crystallinity, lower water absorption, and thermal stability, making it a promising candidate for replacing conventional plastic drinking straws.

Protective potential of fresh orange juice against zinc oxide nanoparticles-induced trans-placental and trans-generational toxicity in mice.

Due to the emerging applications of nanoparticles, human exposure to nanoparticles is unavoidable, particularly to zinc oxide nanoparticles (ZnO NPs), owing to their wide range of usage. The ongoing study aimed to evaluate trans-generational toxic potential of ZnO NPs through exposure to F0 mothers, in F1 pups and F1 mature offspring and the protective potential of fresh orange juice (OJ). Twenty-eight F0 mothers were randomly allocated into four groups (n = 7), control; untreated, dose group; exposed to ZnO NPs, dose+antidote group; coadministered ZnO NPs + OJ, antidote group; OJ, during the organogenetic period. Fifty percent of F0 mothers were subjected to cesarean sections on the 18th day of gestation and F1 pups were recovered, macro-photographed, and dissected for liver evisceration, while 50% of F0 mothers underwent standard delivery. After parturition, F1 offspring were examined, and the liver and blood samples were extracted. Observations showed that ZnO NPs exposure in F0 mothers in preparturition and postparturition resulted in decreased body weight, increased liver weight, and elevated levels of ALT and AST significantly p ≤ .05 as compared to the control and antidote groups. Histopathological analysis of maternal livers intoxicated with NPs showed the disruptive structure of central vein, hepatocytes, and Kupffer cells in F0 mothers, while F1 pups showed morphological deviations and distorted development of the liver tissue and congestion, in contrast to the control. F1 offspring of NPs exposed mothers, even at postnatal week 8 showed pyknotic nuclei and activated Kupffer cells in the liver sections against control. But in the case of the Dose+antidote group, alterations were less severe than in the dose group. It can be concluded that exposure to ZnO NPs instigates teratogenicity and hepatotoxicity in F1 pups, F0 mothers, and F1 offspring, respectively, while fresh orange juice acts as a remedial agent against the abovementioned toxicities.

Inactivation of pectinmethylesterase in fresh orange juice by cold atmospheric plasma technology: A kinetic study

Preservation of fruit juices requires the inactivation of natural endogenous enzymes, such as pectinmethylesterase (PME). Within this work, cold atmospheric plasma (CAP), and in particular a dielectric barrier plasma jet fed with helium gas, was demonstrated to effectively inactivate PME of freshly squeezed orange juice in short treatment times (2–30 min). By a combination of temperature measurements and a multidimensional heat transfer model, the temperature profile of the whole sample during plasma treatment was extracted. It was found that the thermal phenomena were not a driving factor for PME inactivation. Plasma treatment of orange juices resulted in inactivation of 55–80% of PME with <5.0% of PME inactivation caused by the temperature increase from 20 to 90 °C. The Weibull distribution model compared to the first-order fractional, the sigmoidal logistic and the Hulsheger's kinetic models was found to better describe mathematically (R2 > 0.99; Af = 1.002–1.052) the effect of CAP processing on residual PME activity. Multi-parameter equation fits allowed the prediction of residual PME activity as a function of the applied voltage, helium flow, and treatment time. Generally, higher voltages and lower helium flows applied led to higher PME inactivation rates in fresh orange juice.

Metabolomic profiles of not from concentrate orange juice after different sterilization treatments based on HS‐SPME‐GC‐MS and UPLC‐QTOF‐MS

Not from concentrate (NFC) orange juice is minimally processed, natural-appearing food, and has become more popular. Sterilization is an important stage for NFC orange juice production. Here we present a comprehensive analysis of the effect of sterilization on the metabolites of NFC orange juices, including three thermal (pasteurization, high-temperature short time, and ultra-high temperature) and one nonthermal (high hydrostatic pressure) method. A total of 108 metabolites, including 59 volatiles and 49 nonvolatiles were identified in orange juice. Of which, only butyl butanoate and 3-carene were detected in fresh orange juice. Sterilization significantly changed the metabolites of orange juice, and different methods caused various changes. Esters were downregulated by both thermal and nonthermal sterilization, while most flavonoids and terpenes were upregulated. With comparative analyses of three thermal sterilization, we found that high temperature and relatively short-time treatment preserved esters and ascorbic acid more effectively than low temperature and prolonged treatment. Aldehydes, however, were the opposite. Nonthermal sterilization is effective in preserving the metabolites of orange juice, especially for esters, terpenes, and flavonoids. In addition, 19 distinct metabolites were characterized between thermal and nonthermal samples by chemometrics analysis. These findings provide a new sight of the optimization of sterilization methods and references for different types of NFC orange juice identification. PRACTICAL APPLICATION: This study provides a reference for the optimization of sterilization methods and identification of HHP and thermal NFC orange juice and also benefits the purchase of consumers.

Evaluation of Active LDPE Films for Packaging of Fresh Orange Juice

Microbial development, enzymatic action, and chemical reactions influence the quality of untreated natural orange juice, compromising its organoleptic characteristics and causing nutritional value loss. Active low-density polyethylene (LDPE) films containing green tea extract (GTE) were previously prepared by a blown film extrusion process. Small bags were prepared from the produced films, which were then filled with fresh orange juice and stored at 4 °C. Ascorbic acid (AA) content, sugar content, browning index, color parameters, pH, total acidity (TA) and microbial stability were evaluated after 3, 7, and 14 days of storage. The packaging containing GTE maintained the microbial load of fresh juice beneath the limit of microbial shelf-life (6 log CFU/mL) for the bacterial growth, with a more prominent effect for LDPE with 3%GTE. Regarding yeasts and molds, only the CO_LDPE_3GTE package maintained the microbial load of fresh juice below the limit for up to 14 days. At 14 days, the lowest levels of AA degradation (32.60 mg/100 mL of juice) and development of brown pigments (browning index = 0.139) were observed for the packages containing 3% of GTE, which had a pH of 3.87 and sugar content of 11.4 g/100 mL of juice at this time. Therefore, active LDPE films containing 3% of GTE increase the shelf-life of fresh juice and can be a promising option for storage of this food product while increasing sustainability.

Effect of Pasteurization by Moderate Intensity Pulsed Electric Fields (PEF) Treatment Compared to Thermal Treatment on Quality Attributes of Fresh Orange Juice.

Novel pulsed electric field (PEF) process conditions at moderate electric field strength and long pulse duration have recently been established to obtain microbial inactivation. In this study, the effect of these PEF conditions (E = 0.9 and 2.7 kV/cm, with pulse duration 1000 µs) at variable maximum temperatures was evaluated on quality attributes of freshly squeezed orange juice. Results were compared to orange juice that received no treatment or a mild or severe thermal pasteurization treatment. No differences for pH and soluble solids were found after application of any treatment, and only small differences were observed for color and vitamin C content (ascorbic acid and dehydroascorbic acid) after processing, mainly for conditions applied at higher temperature. Variations in the maximum temperatures of the PEF and thermal processes led to differences in flavor compounds and the remaining activity of pectinmethylesterase (PME). At PEF conditions with a maximum temperature of 78 °C or higher, PME activity levels were below a critical value, meaning that the cloud is stable. At this temperature volatiles associated with fresh juice (such as octanal and nonanal) are statistically identical to untreated juice, while they are statistically distinguishable from thermal treated. This papers demonstrates the potential of using moderate intensity PEF as an adequate alternative to thermal pasteurization of orange juice with a better retention of the fresh flavor.

Asset-Based Community Development: Pengembangan Produk Pertanian Sari Jeruk Khas Dusun Precet

Oranges are a type of fruit that contains lots of vitamin C and fiber. One of the citrus producing places in Malang is Dusun Precet, which is part of Sumbersekar Village. The abundant citrus plantation products in Precet Hamlet have not been further processed by the residents, so the price falls during the harvest season. Farmers left some of it to rot in the garden, because the cost of picking during the harvest season is more expensive than the selling prices. Whereas the oranges can have a higher selling value if it is processed into orange juice products. The Asset-Based Community Development (ABCD) strategy was implemented by the UIN Maulana Malik Ibrahim Malang team in the form of training activities for processing orange juice products. The basic mindset in ABCD theory on assisted objects has five key steps, namely discovery, dream, design, define, and destiny. Assets that support the ABCD theory in assisted objects are categorized into four, namely human assets, natural assets, economic assets, and social assets. Dusun Hamlet is potential place to process citrus fruits becomes fresh orange juice that can be consumed by the wider community. Moreover, orange juice is produced without using preservatives so that it can be consumed by various ages.

Characterization and Differentiation of Fresh Orange Juice Variety Based on Conventional Physicochemical Parameters, Flavonoids, and Volatile Compounds Using Chemometrics.

The present study focused on the possibility of differentiating fresh-unprocessed orange juice according to botanical origin (variety), based on the use of conventional physico-chemical parameters, flavonoids, and volatile compounds, in combination with chemometrics. For this purpose, oranges from seven different varieties were collected during the harvest years of 2013–2014 and 2014–2015 from central and southern Greece. The physico-chemical parameters that were determined included: electrical conductivity, acidity, pH, and total soluble solids. The flavonoids: hesperidin, neohespseridin, quercetin, naringin, and naringenin were determined using high-performance liquid chromatography (HPLC-DAD). Finally, volatile compounds were determined using headspace solid-phase micro-extraction in combination with gas chromatography-mass spectrometry (HS-SPME/GC-MS). Statistical treatment of data by multivariate techniques showed that orange juice variety had a significant (p < 0.05) impact on the above analytical parameters. The classification rate for the differentiation of orange juice according to orange variety using multivariate analysis of variance (MANOVA) and linear discriminant analysis (LDA) was 89.3%, based on the cross-validation method.

Zeolitic imidazolate framework-8 capped gold nanoclusters as an “on-off-on” fluorescent nanoprobe for sensitive detection of MnO4− and ascorbic acid

Herein, zeolitic imidazolate framework-8 capped gold nanoclusters (AuNCs@ZIF-8) was fabricated and developed as an “on-off-on” fluorescent nanoprobe for selectively and sensitively detecting KMnO4 and ascorbic acid (AA). The prepared AuNCs@ZIF-8 initially exhibited strong fluorescence at 595 nm KMnO4 could quench the fluorescence of AuNCs@ZIF-8, rendering the fluorescence signal of AuNCs@ZIF-8 in the “off” state. The probe allows KMnO4 to be detected with a 10 nM detection limit and the linear analytical range was 0.05–2 μM. When AA was added into the AuNCs@ZIF-8/KMnO4 system, the fluorescence of the AuNCs@ZIF-8 recovered due to the redox reaction between KMnO4 and AA, and the fluorescence signal of the system turned “on”. The detection limit of AA was 37 nM in a good linear concentration range of 0.05–5 μM. Furthermore, this AuNCs@ZIF-8 nanoprobe was successfully used for AA detecting in fresh orange juices with the recoveries ranged from 96.6% to 108.2%, which validates the potential applicability of this strategy.

Fluorescence and UV/visible spectroscopic investigation of orange and mango fruit juice quality in case of Adama Town.

Extracted Mango and Orange juices were investigated by using spectroscopic techniques such as UV/Visible and Fluorescence. Three portions of samples (fresh juice) were stored at 22 °C for eight days, stored in a water bath and heated at 40 °C, 60 °C, and 80 °C for ten minutes. The highest wavelengths (455 nm) were observed from the UV/Vis results for fresh Mango juices, while 270 nm and 460 nm were observed for stored Mango juices. Furthermore, wavelengths of 320 nm were observed in heat-treated mango juice (40 °C). No absorption peaks were observed at 60 °C and 80 °C due to temperature effects. Absorption peaks of fresh fruit were observed at 330 nm and 390 nm, while 260 nm and 320 nm reflect stored orange juices absorptions peaks. From heat-treated stored (40 °C and 60 °C) samples, 320 nm and 260 nm absorption peaks were observed, respectively. Wavelength observed (454 nm, 540 nm & 700 nm) peaks represent the fresh mango juice spectra, while 460 nm and 700 nm are for stored Mango juices. The peaks observed in the region of 400–500 nm and at 700 nm represent heat-treated mango juices at 40 °C. Heat stored Mango juices (60 °C & 80 °C) have peaks at 700 nm. Peaks observed at 700 nm, 500 nm, and 455 nm reflect fresh orange juice, while 460–500 nm and 700 nm represent the emission spectra of the samples. The stored orange juice peaks at 460–500 nm and at 700 nm, but heated-stored orange juice peaks only at 700 nm. The pH values for orange and mango juices were 3.52–3.73 and 4.02–4.72, respectively.

Role of hesperidin and fresh orange juice in altering the bioavailability of beta-blocker, metoprolol tartrate. An in vivo model

The aim of my study was to find the effect of co-administrating orange juice and hesperidin on the bioavailability of metoprolol tartrate in rabbits. Metoprolol tartrate (10 mg/kg) was given orally to rabbits with hesperidin (10 mg/kg) and with orange juice (6 mL/kg) separately. The plasma concentrations of metoprolol tartrate were determined using reverse phase-high performance liquid chromatography at 1.5, 1, 2, 4, and 6 h, and the pharmacokinetic parameters were studied. In comparison to the control group, the AUC of metoprolol tartrate was increased significantly by 68.32% with hesperidin while orange juice substantially reduced the AUC by 37.08%. However, no significant change was observed in Tmax , Kel , and Vd in both groups. The relative bioavailability of metoprolol tartrate with hesperidin was 168.3% as compared to orange juice, that is, 62.9%. The present study revealed that the concurrent intake of hesperidin with metoprolol tartrate increased its bioavailability while orange juice administration suppressed its bioavailability. The change in bioavailability of metoprolol tartrate might be due to alterations in the activity of cytochrome P450 enzymes involved in the metabolism of metoprolol tartrate. However, the exact mechanism is still not known. These interactions may be of clinical significance.

Microbiological quality and presence of foodborne pathogens in fresh-squeezed orange juice samples purchased from street vendors and hygienic practices in Morelia, Mexico

Few studies have screened fresh orange juice for the presence of foodborne pathogens. This study therefore evaluated the microbiological quality and occurrence of Salmonella, Shigella, Escherichia coli, and diarrheagenic E. coli pathotypes (DEP) in fresh-squeezed orange juice purchased from street vendors in Morelia, Michoacan, Mexico. The general hygienic practices of street vendors were poor. All 100 samples analyzed were positive for aerobic mesophilic bacteria, with concentrations ranging from 2.41 to 6.03 log CFU/mL. A total of 90 (90%), 35 (35%), and 14 (14%) samples were positive for total coliforms, fecal coliforms, and E. coli, respectively, present with concentrations ranging from < 1 to 4.84 log CFU/mL, < 3 to > 1,100 MPN/mL, and < 3 to 210 MPN/mL, respectively. Salmonella was not detected in any of the samples, whereas Shigella sonnei was isolated from one sample. Two samples were positive for DEP; one harbored ETEC strains and the other STEC strains. Our results highlight the elevated risk for consumer health associated with the ingestion of fresh-squeezed orange juice.