Adulteration Of Fruit Juices Research Articles

New and Advanced Methods in Detection of Fruit Juice Adulteration: Focusing on Nano‐Biosensor

One of the most popular products made from fruit is juice, which is consumed as a snack by people of all ages due to its high content of polyphenols and vitamins. Therefore, the prevalence of adulteration in juices is very high, and ensuring the authenticity and quality of juices is a major concern for those responsible for monitoring food safety for the public. The most common frauds in fruit juices include adding water, sugar, organic acids, and other juices clouding agents and exceeding the permitted amount of sulfites. Having knowledge of the types of fraud in fruit juices and their detection methods is essential for developing more efficient detection methods. Chromatographic techniques, such as high‐performance liquid chromatography (HPLC) and gas chromatography (GC), are commonly used to determine the purity of fruit juices. Among the new methods for detecting counterfeit fruit juice, the development of bio‐nanosensors is particularly notable. These sensors reduce sample volume, analytical time, costs, and solvent consumption and will be discussed further in this study. Therefore, this review will explain the basic analytical approaches and chemometric tools used to assess the authenticity of fruit juice and identify any adulteration in the juice.

Assessment of adulteration of fruit juices by water dilution using NIR spectroscopy

Assessment of adulteration of fruit juices by water dilution using NIR spectroscopy

Detection of fruit juice adulteration by laser backscattering imaging

Detection of fruit juice adulteration by laser backscattering imaging

Pomegranate fruit juice adulteration with apple juice: detection by UV\u2013visible spectroscopy combined with multivariate statistical analysis

Pomegranate is rich in high value nutritional substances known to be beneficial against several diseases and its use in medicine is known since ancient times. Due to its properties and delicious taste, pomegranate fresh fruit juices demand has been growing worldwide and its adulteration is becoming a problem. Low-cost, user friendly and fast detection methods are therefore desirable in order to easily and rapidly detect adulteration of short shelf-life fresh fruit juices. For this purpose fresh squeezed arils pomegranate juice samples adulterated with less expensive apple juice concentrate were investigated by UV–visible spectroscopy combined with multivariate statistical analysis. Unsupervised principle component analysis (PCA), supervised projection to latent structure discriminant analysis (PLS-DA) and orthogonal projection to latent structure discriminant analysis (OPLS-DA) were performed on the full spectra. OPLS-DA analysis of UV–visible spectra proved to be a suitable method to detect pomegranate juices adulterated by more than 20% v/v apple juice concentrate.

Use of 1H NMR to Detect the Percentage of Pure Fruit Juices in Blends

The consumption of high-nutritional-value juice blends is increasing worldwide and, considering the large market volume, fraud and adulteration represent an ongoing problem. Therefore, advanced anti-fraud tools are needed. This study aims to verify the potential of 1H NMR combined with partial least squares regression (PLS) to determine the relative percentage of pure fruit juices in commercial blends. Apple, orange, pineapple, and pomegranate juices were selected to set up an experimental plan and then mixed in different proportions according to a central composite design (CCD). NOESY (nuclear Overhauser enhancement spectroscopy) experiments that suppress the water signal were used. Considering the high complexity of the spectra, it was necessary to pretreat and then analyze by chemometric tools the large amount of information contained in the raw data. PLS analysis was performed using venetian-blind internal cross-validation, and the model was established using different chemometric indicators (RMSEC, RMSECV, RMSEP, R2CAL, R2CV, R2PRED). PLS produced the best model, using five factors explaining 94.51 and 88.62% of the total variance in X and Y, respectively. The present work shows the feasibility and advantages of using 1H NMR spectral data in combination with multivariate analysis to develop and optimize calibration models potentially useful for detecting fruit juice adulteration.

Awareness Situation Regarding Fruit Juice Adulteration among the Public University Students of Bangladesh: A Case from University of Dhaka

Awareness Situation Regarding Fruit Juice Adulteration among the Public University Students of Bangladesh: A Case from University of Dhaka

Assessment of fruit juice authenticity using UPLC–QToF MS: A metabolomics approach

In recent years, with the growing complexity of global food supply chains and trade, food fraud, including adulteration of high value foods with cheaper substitutes, has become an increasingly important issue. A metabolomics approach can be applied to discover biomarkers that can be used to trace food adulteration. A study was undertaken to discover novel, potential biomarkers for the rapid detection of the adulteration of fruit juices with cheaper alternatives. Pineapple, orange, grapefruit, apple, clementine, and pomelo were investigated. Untargeted metabolite fingerprinting was performed by UPLC–QToF MS with multivariate data analysis. Twenty-one differential metabolites were selected, contributing to the separation between pineapple, orange and grapefruit juices, and their admixtures down to 1% adulteration level. A targeted metabolomics method was then optimised and adulteration could be detected at 1%. The results demonstrate that metabolomics has potential as a screening tool for the rapid detection of food adulteration.

Evaluation of herb and fruit juice adulteration and authenticity by coulometric array detection and pattern recognition analysis

Evaluation of herb and fruit juice adulteration and authenticity by coulometric array detection and pattern recognition analysis

Survey of South African fruit juices using a fast screening HILIC-MS method

Adulteration of fruit juices – by the addition of sugar or other less expensive fruit juices as well as preservatives, artificial sweeteners and colours – was tested for by using a developed screening method. The method employs hydrophilic interaction liquid chromatography-mass spectrometry (HILIC-MS) using electrospray ionisation in the negative mode and ultraviolet light detection. Different fruit juices can be differentiated by the content of marker compounds like sorbitol, certain phenolic molecules and their saccharide profile. This method was used to test 46 fruit juice samples from the retail market as well as 12 control samples. The study focused on the main types of fruit juices consumed on the South African market including apple, orange, grape and blends of these juices with other fruits like mango, pear and guava. Overall, the 46 samples tested mostly agreed with label claims. One grape juice sample was adulterated, probably with apple juice. Natamycin above the legal limits was found in two samples. In addition, two samples contained natamycin and one sample benzoate without it being indicated on the label. The method is well suited as a quick screening method for fruit juice adulteration and if used routinely would reduce fruit juice adulteration without the cost of the current array of tests needed for authenticity testing.

Quality assessment of fruit juices by NIR spectroscopy

In the article there is described the detection of substances used for adulteration of fruit juices. They were investigated in juice products distributed within the network of retail markets. This detection was performed using the method of near-infrared spectroscopy (NIR). There were analysed samples of orange juices, apple juices, and grapefruit juices. At the beginning, there were assessed quality parameters (soluble dry matter, total acids, formol number, malic acid, citric acid, ascorbic acid, lactic acid, specific density, and ethanol content) and their compatibility with the limit values specified by the Association of the Industries of Juices and Nectars. The research covered 45 kinds of fruit juices and there was found 10 cases when at least one parameter was out of the approved limits. After that there was used the discrimination analysis and it enabled to separate pure juices from those containing at least 1 % of admixtures. This method also helped to distinguish between the group of fresh squeezed juices and the juices made of fruit concentrates. Using the diagnostics “Principal Component Scores 3D Display”, there were arranged various numbers of similar groups of juice samples with similar compound profiles.

Determination of α‐hydroxy acids and their enantiomers in fruit juices by ligand exchange CE with a dual central metal ion system

The content of α-hydroxy acids and their enantiomers can be used to distinguish authentic and adulterated fruit juices. Here, we investigated the use of ligand exchange CE with two kinds of central metal ion in a BGE for the simultaneous determination of enantiomers of dl-malic, dl-tartaric and dl-isocitric acids, and citric acid. Ligand exchange CE with 100 mM d-quinic acid as a chiral selector ligand and 10 mM Cu(II) ion as a central metal ion could enantioseparate dl-tartaric acid but not dl-malic acid or dl-isocitric acid. Addition of 1.8 mM Sc(III) ion to the BGE with 10 mM Cu(II) ion to create a dual central metal ion system permitted the simultaneous determination of these α-hydroxy acid enantiomers and citric acid. The proposed ligand exchange CE was thus well suited for detecting adulteration of fruit juices.

Evaluation of Herb and Fruit Juice Adulteration and Authenticity by Coulometric Array detection and Pattern Recognition Analysis

Evaluation of Herb and Fruit Juice Adulteration and Authenticity by Coulometric Array detection and Pattern Recognition Analysis

Determination of gallic acid with 4-nitrobenzenediazonium tetrafluoroborate by diffuse reflectance spectrometry on polyurethane foam

AbstractThe present work describes a rapid and cost-effective analytical procedure for the determination of gallic acid. It is basedon the solid-phase extraction of gallic acid in the form of the azo compound by polyurethane foam (PUF) and measurementby diffuse reflectance spectrometry. The calibration graphs are linear over the range 0.2–6 gml −1 . The developed procedurewas applied to the determination of gallic acid in alcoholic beverages.© 2002 Elsevier Science B.V. All rights reserved. Keywords: Gallic acid; Polyurethane foam; Sorption; Diffuse reflectance spectrometry 1. IntroductionGallic acid (2,3,4-trihydroxybenzoic acid) is a natu-ral phenolic compound which is widely distributed inplants. Some pharmacological properties of this sub-stance have been described previously. For example,it has strong antimutagenic, anticarcinogenic and an-tioxidant activities [1–3]. The antioxidant activity andantiradicalar power of gallic acid have been estimatedquantitatively [1].Along with other polyphenolic compounds, gallicacid is often used as an indicator of adulteration of fruitjuices [2,4] and different alcoholic beverages [5–7].For instance, cognac and scotch whisky contain gal-lic acid, and as was shown [5], there was a good

Synergy between Liquid Chromatographic–Pulsed Amperometric Detection and Capillary-Gas Chromatographic Methods for the Detection of Juice Adulteration

The use of liquid chromatography linked with pulsed amperometric detection, and capillary-gas chromatography to detect the adulteration of fruit juices is discussed. These are 2 complementary approaches which can be used to detect the addition of sugar syrups to juices at low levels.

Determination of saccharides in fruit juices by capillary electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

A fast method for the detection of cheap sweeteners is presented. Detecting the adulteration of foods rich in carbohydrates is complicated by the presence of variety of commercial sweeteners that are designed to match exactly the major carbohydrate profiles of these foods. Electrophoretic and mass spectrometric assays for the determination of fruit juice authenticity were developed. Capillary zone electrophoresis with indirect detection was employed to detect adulteration of juices demonstrated by the ratio of the concentrations of major low molecular mass saccharides (glucose, fructose and sucrose). Traces of oligosaccharides, which are not present in the sugar profiles of citrus fruits but are present in inexpensive sweeteners, were evaluated as the other group of target compounds. The fast determination of oligomeric starch hydrolysates in a complex matrix was tested by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and applied to orange juice. MALDI-TOFMS was shown to be a suitable method for the identification of adulteration of fruit juices by starch hydrolysates. The effects of the presence of salts and low molecular mass saccharides on the detection of oligosaccharides by MALDI-TOFMS were studied. Low molecular mass saccharides and organic acids decrease the detectability of oligosaccharides by MALDI-TOFMS, but the concentration of maltooligosaccharides present in juices sweetened with starch hydrolysates is high enough to be detected with good sensitivity.

A continuous spectrophotometric system for the discrimination/determination of monosaccharides and oligosaccharides in foods

A simple, rapid method for the spectrophotometric discrimination of monosaccharides from the oligosaccharide fraction of fruit juice, jam, syrup and honey samples is proposed. The sample, in alkaline medium, is directly introduced into a flow system and passed through an activated carbon column for its decolourization; then, a volume of 200 μl is injected into the derivatising reagent stream to start the analytical reaction, which takes place at 85°C. The two fractions are discriminated on the basis of the different colours of the derivatives formed; thus, the derivatives of the monosaccharides are yellow while those of the di- and trisaccharides are violet-carmine. The two fractions are monitored at 400 and 540 nm, respectively. Sucrose gives no reaction as it is a non-reducing sugar. The proposed method allows reducing sugars contents from 0.01% to 0.80% w/v to be determined with an average relative standard deviation of 4.5% and a sampling frequency of 10 h −1. The proposed method was validated by applying it to two milk-based and sugar candidate artificial CRMs, with good correlation. The detection limits achieved (0.01% w/v for maltose, lactose and maltotriose at 540 nm) allow adulteration of fruit juices with high fructose syrup from starch at the 4% level to be detected.

Determination of the [formula omitted] contents of organic acids and sugars in fruit juices: an inter-comparison study

The determination of the repeatability ( r) and reproducibility ( R) of the ( 13 C/ 12 C) measurement in sugars and organic acids contained in different fruit juices was conducted on an international basis involving 17 laboratories. The mean values of r‰ ( R‰) for acids and sugars are, respectively, equal to 0.58 (1.75) and 0.34 (0.71) and the relatively large values observed for R of acid determinations are related to the preparation step. However, the least significant difference computed for several pairs of natural and spiked juices indicate that the 13 C method can be applied for detecting fruit juice adulteration.

Proteins As Intermolecular Isotope Reference for Detection of Adulteration of Fruit Juices

The fruit proteins, defined as the fraction obtained after bentonite precipitation on a centrifuged juice or diluted concentrate, are proposed as internal standard for δ13C measurements of fruit ju...

Adulteration of Fruit Juices: Dihydrochalcones as Quality Markers for Apple Juice Identification

Some phenolic compounds, (+) catechin, (−) epicatechin, chlorogenic acid, phloretin glucoside (phloridzin) and phloretin xyloglucoside, in several juice samples were separated and identified by reversed phase high performance liquid chromatography/diode array detection (RP-HPLC/DAD). Dihydrochalcones were identified as ‘markers’ in apple samples, their content was calculated and a ‘threshold concentration’ for detectable addition was evaluated. The direct injection method gives excellent recovery, accuracy and precision with a detection limit of 1.6 mg/L.

Interpretation of Combined H SNIF/NMR and C SIRA/MS Analyses of Fruit Juices To Detect Added Sugar

The site-specific natural isotopic fractionation studied by nuclear magnetic resonance (SNIF/NMR) method measures site-specific isotope contents in a variety of organic compounds by deuterium nuclear magnetic resonance spectroscopy. This technique, together with SIRA/MS (stable isotope ratio analysis/mass spectrometry) provides a powerful tool for food authentication and characterization. By using the ethanol resulting from sugar fermentation as a molecular probe, SNIF/NMR (deuterium) and SIRA/MS (13C) have been used together for authentication of fruit juices. The influence of deuterium content of the fermentation water on the isotopic parameters is shown and a means for normalizing the results is proposed. A large number of authentic juices have been analyzed to define the variation of isotopic ratios in natural juices. On the basis of these data, a set of rules was designed to enable interpretation of isotopic parameters in terms of possible adulteration of fruit juices by sugar addition. Results of analyses of Florida orange juice are presented. Orange juice samples from Brazil and Israel are included as 2 extreme cases. Assignment limits for a sample of orange juice of unknown origin also are given. These assignment limits are also provided for apple and grapefruit juices.