Detection In Wine Research Articles

Headspace detection of ethanethiol in wine by cobalt phthalocyanine modified screen-printed carbon electrodes

The formation of thiols has a notable and detrimental sensory impact, especially in the aroma of bottled wines. Their detection in wine is of great interest to avoid important economic and image losses for wineries. This work reports the study of different cobalt phthalocyanine/nanomaterials-based sensors for the headspace detection of volatile thiols. The amperometric procedure based on the use of carbon sensors simply modified with cobalt phthalocyanine showed the best performance. Under the optimum conditions of applied potential, +0.8 V, and pH of the supporting electrolyte, 2.6, this procedure shows a reproducibility of 7% (n = 5) in terms of relative standard deviation of the slopes of calibration curves built in the concentration range from 9.9 to 82.6 μg/L, a capability of detection of 12.5 μg/L and a decision limit of 6.5 μg/L (α = β = 0.05). The use of this electrocatalytic material and the headspace measurements reduce interferents, increasing the selectivity of the procedure, which allows the easy and successful quantification of ethanethiol in white and red wines.

4-ethyphenol detection in wine by fullerene modified screen-printed carbon electrodes

This work shows the potential of modified screen-printed carbon electrodes (SPCEs) for sensitive and selective detection of 4-ethylphenol in wine. Gold nanoparticles (AuNPs) and fullerene C60 (C60), modified sensors have been compared. pH of the supporting electrolyte, deposition time and working temperature have been optimized considering their influence in the voltammetric pulse response of 4-ethylphenol. Under the optimal conditions of measurement, the developed activated C60/SPCE (AC60/SPCE) shows the best performance, with a detection capability of 400 μg/L and 700 μg/L, when using deposition times of 14 min and 6 min, respectively (α = β = 0.05). The reproducibility of the developed sensor resulted better when a deposition time of 6 min was used (5.4 %, n = 3). The influence of different interferents on the analytical response has been studied, as well as their application in the determination of 4-ethylphenol in different wine samples.

Smartphone biosensor for point-of-need chemiluminescence detection of ochratoxin A in wine and coffee

Exposure to mycotoxins, which may contaminate food and feed commodities, represents a serious health risk for consumers. Ochratoxin A (OTA) is one of the most abundant and toxic mycotoxins, thus specific regulations for fixing its maximum admissible levels in foodstuff have been established. Lateral Flow ImmunoAssay (LFIA)-based devices have been proposed as screening tools to avoid OTA contamination along the whole food chain. We report a portable, user-friendly smartphone-based biosensor for the detection and quantification of OTA in wine and instant coffee, which combines the LFIA approach with chemiluminescence (CL) detection. The device employs the smartphone camera as a light detector and uses low-cost, disposable analytical cartridges containing the LFIA strip and all the necessary reagents. The analysis can be carried out at the point of need by non-specialized operators through simple manual operations. The biosensor allows OTA quantitative detection in wine and coffee samples up to 25 μg L−1 and with limits of detection of 0.3 and 0.1 μg L−1, respectively, which are below the European law-fixed limits. These results demonstrate that the developed device can be used for routine monitoring of OTA contamination, enabling rapid and reliable identification of positive samples requiring confirmatory analysis.

Magnetic immunochromatographic test for histamine detection in wine

Histamine, a biogenic amine, is abundant in fermented foods and beverages, notably wine. A high intake of this monoamine may produce adverse reactions in humans, which may be severe in individuals with a reduced capacity to catabolise extrinsic histamine. Thus, control of histamine concentration during wine production and before distribution is advisable. Simple, rapid, point-of-use bioanalytical platforms are needed because traditional methods for the detection and quantification of histamine are expensive and time-consuming. This work applies the lateral flow immunoassay technique to histamine detection. Superparamagnetic particle labels, and an inductive sensor designed to read the test line in the immunoassay, enable magnetic quantification of the molecule. The system is calibrated with histamine standards in the interval of interest for wine production. A commercial optical strip reader is used for comparison measurements. The lateral flow system has a limit of detection of 1.2 and 1.5mg/L for the inductive and optical readers, respectively. The capability of the inductive system for histamine quantification is demonstrated for wine samples at different processing points (at the end of alcoholic fermentation, at the end of malolactic fermentation, in freshly bottled wine, and in reserve wine). The results are validated by ultra-high-performance liquid chromatography. Graphical abstract.

Botanical and commercial characterisation of gum arabic and its detection in wine using non-targeted high resolution mass spectrometry

Gum arabic (GA) is the oldest and best known of all natural gums. Thanks to the particular characteristics resulting from its complex mixture of polysaccharides and glycoproteins, its field of application is extensive. In the oenological sector, it is used to prevent colour depigmentation and protein precipitation and although there is no declared limit, the International Code of Oenological Practices suggests not exceeding a dosage of 300 mg L−1.In this study, the botanical origin (Acacia senegal vs A. seyal) and commercial description (Kordofan region vs other Sub-Saharan areas, based on the traditional geographic provenance) were defined studying 44 GA samples with a non-targeted screening approach using high resolution mass spectrometry. From an initial group of 88 identified masses, 15 were selected to create a bi-factor PLS-DA statistical model able to correctly reclassify samples with 94.4% accuracy. Moreover, the study addressed the question of identifying gum addition in wines, analysing 98 untreated wines and comparing them with 40 wines to which gum arabic had been added (200 mg L−1). Considering the database of 88 masses, 4 of them were established to be markers of gum arabic addition (m/z 152.1067, 166.1225, 585.1428 and 643.1403). Principal component analysis performed with the signal (area) of the 4 masses highlighted three groupings differentiating untreated wines, wines treated with A. senegal gum and wines treated with A. seyal gum. m/z 152.1067 was tentatively identified as N-methyltyramine, while m/z 166.1225 as N,O-dimethyltyramine.

A Visible Colorimetric Fluorescent Probe for Hydrogen Sulfide Detection in Wine.

A new efficient and practical fluorescent probe 6-(benzo[d]thiazol-2-yl)naphthalen-2-yl-thiophene-2-carboxylate (probe 1) was synthesized to detect hydrogen sulfide (H2S). The addition of H2S caused the solution of probe 1 to change from colorless to yellow, and the solution of probe 1 changes to different colors with respect to different concentrations of H2S. Importantly, probe 1 could help detect H2S efficiently by a distinct color response as a visible detection agent. Probe 1 reacted with various concentrations of H2S (0–200 μM), and the detection limit for H2S was 0.10 μM. Particularly, probe 1 can be applied as a sensor to detect H2S accurately in wine samples.

Validation of a gas chromatography-flame ionization method for quality control and spoilage detection in wine and cider

A GC-FID method for major volatile analysis in cider and wine was validated under the requirements of the ISO/IEC 17025 regulation using a split mode injection. This method presented a good linearity (R2>0.999, Cm>99%), a wide range of calibration, the maximum random errors for repeatability and intermediate precision were 5% and 8%, respectively, and the maximum limit of quantification and limit of detection were 14.1 mg l–1 and 4.6 mg l–1, respectively. Trueness, expressed as recovery (%), was successfully validated by means of two different methods, standard addition (92–110%) and comparison against reference materials (93–115%). Expanded uncertainty estimated at 95% confidence level ranged between 11% for methanol and 7% for allyl alcohol. The validated method was successfully applied for the analysis of major volatiles in ciders and wines, and to detect yeast and lactic acid bacteria spoilage.

Highly selective and rapidly responsive fluorescent probe for hydrogen sulfide detection in wine

A new fluorescent probe 6-(2, 4-dinitrophenoxy)-2-naphthonitrile (probe 1) was designed and synthesized for the selective detection of hydrogen sulfide (H2S). The addition of H2S to a solution of probe 1 resulted in a marked fluorescence turn-on alongside a visual color change from colorless to light yellow. Importantly, this distinct color response indicated that probe 1 could be used as a visual sensor for H2S. Moreover, probe 1 was successfully used as a signal tool to determine the H2S levels in beer and red wine.

Nitrogen-Doped Graphic Carbon Protected Cu/Co/CoO Nanoparticles for Ultrasensitive and Stable Non-Enzymatic Determination of Glucose and Fructose in Wine

Food safety has always been a very serious and global concern. Content determination of each component is one of the most routine analyses in food testing. Here, nitrogen-doped graphic carbon (NGC)-coated Cu/Co/CoO nanoparticles (Cu/Co/CoO/NGC) show excellent performance for glucose and fructose detection in wine. The high sensitivity (1,035 μA mM−1 cm−2), low determination (0.2 μM) and large linear range (10-9,300 μM) characteristic of the Cu/Co/CoO/NGC sensor are attributed to the synergistic effect between the Cu, Co and CoO nanoparticles coated by NGC and the catalytically active M-Nx moieties (M = Cu and Co). Importantly, the good stability and antioxidation of the Cu/Co/CoO/NGC electrode result from the protection provided by the NGC shell. In addition, disposable, low-cost, and compact screen-printed carbon electrodes (SPCEs) modified by the Cu/Co/CoO/NGC (Cu/Co/CoO/NGC/SPCEs) were used to detect the sugar content in wine samples with a good reliability (R.S.D. = 1.7%) and recovery (103.2%). Thus, Cu/Co/CoO/NGC/SPCEs will be popular in the detection of real samples.

Headspace solid-phase microextraction and gas chromatographic analysis of low-molecular-weight sulfur volatiles with pulsed flame photometric detection and quantification by a stable isotope dilution assay.

Low-molecular-weight volatile sulfur compounds such as thiols, sulfides, disulfides as well as thioacetates cause a sulfidic off-flavor in wines even at low concentration levels. The proposed analytical method for quantification of these compounds in wine is based on headspace solid-phase microextraction, followed by gas chromatographic analysis with sulfur-specific detection using a pulsed flame photometric detector. Robust quantification was achieved via a stable isotope dilution assay using commercial and synthesized deuterated isotopic standards. The necessary chromatographic separation of analytes and isotopic standards benefits from the inverse isotope effect realized on an apolar polydimethylsiloxane stationary phase of increased film thickness. Interferences with sulfur-specific detection in wine caused by sulfur dioxide were minimized by addition of propanal. The method provides adequate validation data, with good repeatability and limits of detection and quantification. It suits the requirements of wine quality management, allowing the control of oenological treatments to counteract an eventual formation of excessively high concentration of such malodorous compounds.

Use of anchor protein modules in fluorescence polarisation aptamer assay for ochratoxin A determination

A new strategy for sensitive fluorescence polarisation (FP) analysis is proposed which uses aptamer as the receptor and anchor protein modules as the enhancers by including the aptamers in complexes with protein modules. This approach is based on increasing the size differences of bound and unbound fluorophores. The strategy was applied in an ochratoxin A (ОТА) assay with the competitive binding of fluorophore-labelled and free OTA with aptamer-based receptors. We showed that the binding of labelled OTA with aptamer included in complexes with anchors led to higher a FP than binding with free aptamer. This allowed the aptamer concentration to be reduced, thus lowering the limit of detection by a factor of 40, down to 3.6 nM. The assay time was 15 min. To evaluate the applicability of the FP assay with aptamer–anchor complex to real samples, we conducted OTA measurements in spiked white wine. The OTA limit of detection in wine was 2.8 nM (1.1 μg/kg), and the recoveries ranged from 83% to 113%. The study shows that the proposed anchor strategy is efficient for increasing the sensitivity of FP-based aptamer assays.

Pesticide residues screening in wine by mass spectrometry

Recently, a study (from PAN Europe) covered 40 bottles of wine – 34 conventional and six organic ones – purchased inside the EU. According to the results, the 34 bottles of conventional wine together contained 148 pesticide residues. All 34 bottles contained from one to ten pesticides, bringing the average per bottle to more than four. Of the six bottles of organic wine tested, one sample contained a low concentration of a possibly carcinogenic pesticide. According to PAN Europe, the “contamination of wines is a direct result of over-reliance on pesticides in grape production”. This study, between others, to prove the importance of develop methods sensivity and confident for pesticide detection in wine. A multi-residue method was developed for the determination ca of 250 pesticide residues in wine using Quechers extraction, gas chromatography-tandem mass spectrometry (GC-MS-MS) and liquid chromatography-tandem mass spectrometry (LC-MS-MS). The method was validated with the evaluation of follow parameters: Linearity, Precision, Accuracy, Matrix effect, Limit of detection and Limit of Quantification. The method was approved and was able to quantify pesticide residues in more than 60 samples of wine.

Lab-on-Spoon – a 3-D integrated hand-held multi-sensor system for low-cost food quality, safety, and processing monitoring in assisted-living systems

Abstract. Distributed integrated sensory systems enjoy increasing impact leveraged by the surging advance of sensor, communication, and integration technology in, e.g., the Internet of Things, cyber-physical systems, Industry 4.0, and ambient intelligence/assisted-living applications. Smart kitchens and "white goods" in general have become an active field of R&D. The goal of our research is to provide assistance for unskilled or challenged consumers by efficient sensory feedback or context on ingredient quality and cooking step results, which explicitly includes decay and contamination detection. As one front end of such a culinary-assistance system, an integrated, multi-sensor, low-cost, autonomous, smart spoon device, denoted as Lab-on-Spoon (LoS), has been conceived. The first realized instance presented here features temperature, color, and impedance spectroscopy sensing in a 3-D-printed spoon package. Acquired LoS data are subject to sensor fusion and decision making on the host system. LoS was successfully applied to liquid ingredient recognition and quality assessment, including contamination detection, in several applications, e.g., for glycerol detection in wine. In future work, improvement to sensors, electronics, and algorithms will be pursued to achieve an even more robust, dependable and self-sufficient LoS system.

Lab-on-Chip Prototype Platform for Ochratoxin A Detection in Wine and Beer

We describe the development of a micro total analysis system for the detection of ochratoxin A (OTA) in wine and beer. The OTA detection strategy is based on an indirect competitive ELISA detection by chemiluminescence with the integration of microfluidics with microfabricated amorphous silicon photodiodes fabricated on glass substrates [1] . The full lab-on-chip (LoC) assay is implemented on a prototype device for fully-automatic measurement and monitoring of photodiode signals and control of fluid handling. The device is composed of three peripheral control and measurement modules: a peristaltic pump, a fluid dispenser for fluid handling, and a multi-sensor data acquisition with custom transimpedance amplifier. A microcontroller interfaces the individual modules with a computer via USB communication. The analysis is run automatically and the results displayed through a PC controlled user interface. OTA was detected in wine and beer extracts down to 0.5 ng/mL.

A novel molecular method for identification of Oenococcus oeni and its specific detection in wine

Oenococcus oeni is a species of lactic acid bacteria with economic interest in winemaking. Using both in silico and in vitro analyses, a molecular method was developed that allows the identification of O. oeni isolates and its detection from wine samples. The method is based on the amplification of 16S rRNA gene with universal primers followed by restriction with the endonuclease FseI, generating two fragments of 326 and 1233 bp. Among wine bacteria, the FseI recognition sequence is only found in the 16S rRNA gene of O. oeni, ensuring the specificity of the method. The use of Whatman FTA cards for DNA extraction and purification is an efficient and interesting alternative to current methods, as samples can be easily collected at wineries by a non-specialized technician, stored at room temperature and sent in a mail envelope to the analytical laboratory for processing. The proposed method, with a detection limit between 10 2 and 10 3 cfu/mL and a full turnaround time of ca. 8 h, ensures the rapid and reliable detection of O. oeni in wine samples during winemaking surveillance and wine quality control.

Comparison of ICP-MS and photometric detection of an immunoassay for the determination of ochratoxin A in wine

An immunoassay was developed for ochratoxin A (OTA) detection in wine and two completely different detection methods were compared: ICP-MS and photometry. For labelling, we applied secondary antibodies conjugated with gold nanoparticles for ICP-MS and with horseradish peroxidase for photometric detection, respectively. Detection limits of the assay were determined as 0.003 µg L−1 for both detection methods. OTA in wine was determined below the EU limit value of 2 µg kg−1. The measurement range was between 0.01 and 1 µg L−1 for ICP-MS and photometric detection. Assay precision detected by ICP-MS and photometry were similar showing that precision of the detection method has only a minor effect on total assay precision. By using BSA as a buffer additive to minimize nonspecific binding, we could also confirm that OTA strongly binds to BSA. In a comparison study of several additives, casein was found to be preferable.

Analysis of wines, grape juices and cranberry juices forAlternaria toxins

Sixty six samples of red and white wine from Ontario (VQA), British Columbia (VQA), Québec ("vins artisanaux"), imported wines (from Italy, South America and USA) and Canadian and US grape and cranberry juices were analysed for theAlternaria mycotoxins alternariol (AOH) and alternariol monomethyl ether (AME). After cleanup on aminopropyl SPE columns, AOH and AME were initially determined by reversed phase LC with UV detection. Positive sample extracts were re-analysed by LC-tandem negative ion electrospray mass spectrometry (MS/MS) in multiple reaction mode. Overall mean method recoveries measured by LC-UV were 93% for AOH and 81% for AME. Limits of detection in wine (and juice) by LC-UV for AOH were 0.8 (0.4) ng/ml and for AME were 0.5 (0.4) ng/ml; they were below 0.01 ng/ml by LC-MS/MS. As determined by LC-MS/MS, AOH was found in 13/17 Canadian red wines at levels of 0.03 to 5.02 ng/ml and in 7/7 imported red wines at 0.27-19.4 ng/ml, usually accompanied by lower concentrations of AME. Red grape juices (5 positive/10 samples) contained only sub ng/ml levels of AOH or AME except for one sample (39 ng AME/ml). White wines (3/23 samples), white grape juices (0/4 samples) and cranberry juices (1/5 samples) contained little AOH/AME (≤1.5 ng/ml).

Coupling gas chromatography and electronic nose for dehydration and desalcoholization of alcoholized beverages: Application to off-flavour detection in wine

Aroma characterization of alcoholic beverages with sensor array electronic noses is a difficult challenge due to the masking effect of ethanol. Back-flush gas chromatography is proposed as a novel tool for the pretreatment of vapour samples before analysis in the electronic nose. The dehydration and desalcoholization step can be conducted in parallel with electronic nose detection, reducing significantly the analysis overall duration. As demonstration application, five molecules responsible for off-flavours in wines have been detected with a FOX 4000 system, after total dehydration and desalcoholization. Principal component analysis showed that discrimination between the control wine and off-flavour doped-wines became easy, even at concentrations corresponding to the human expert perception threshold.

Capillary electrophoresis analysis of trans- and cis-resveratrol, quercetin, catechin and gallic acid in wine

A study was conducted on the use of micellar electrokinetic capillary chromatography (MEKC) in the analysis of trans- and cis-resveratrol, quercetin catechin and gallic acid in wine. Standards and wine samples were directly injected into CE after a simple filtration, under a pressure of 50 mbar. Separation of the compounds was done in bare fused-silica capillary-extended light path with 50 μm i.d. An excellent correlation coefficient ( r = 0.99998) was obtained with a linear analytical response from 8 to 1000 ppm of resveratrol, quercetin, catechin and gallic acid in MEKC. The high separation efficiency obtained recommend CE as a good application for trans- and cis-resveratrol detection in wine.

Highly Sensitive Method for Urea Detection in Wine

ABSTRACTTrace amounts of urea (less than 50 μg/L) in wine were accurately determined using a modified high performance liquid chromatography (HPLC‐fluorometric) technique. Appropriate selection of eluent, HPLC columns, and chiral derivatives for the o‐phthalaldehyde solution provided a 20‐fold enhancement of sensitivity over established methods. A linear relationship was observed at concentrations from 0.5–500 μg/L of aqueous urea solution. The threshold level for detectability of urea in wine was 5 μg/L. The method is simple enough to be applicable to most beverages.