Ochratoxin A in wines,musts and grape juices from Spain

A survey on the occurrence of ochratoxin A (OTA) in 240 grape‐based beverages was carried out. Red and white wines from four different Spanish Designations of Origin (n = 160), musts (n = 20), grape juices (n = 10), ordinary wines (n = 20), special wines (Malaga, muscatel, sherry, vermouth, etc) (n = 20) and sparkling wines (n = 10) were assayed for OTA content using immunoaffinity column clean‐up and high‐performance liquid chromatography with fluorimetric detection (detection limit 0.05 µg l^?1). Forty‐three (17.9%) of the samples tested contained detectable levels of OTA. The overall mean OTA concentration in red and white wines of Designations of Origin was 0.30 and 0.18 µg l^?1 respectively (ranges 0.05–3.19 and 0.05–1.13 µg l^?1 respectively). The percentage of wine samples with detectable amounts of OTA was higher for red (18.3%) than for white (10%) wines. OTA was also found in two of 10 red ordinary wines (0.68 and 4.24 µg l^?1), whereas none of 10 white ordinary wines contained OTA. The mean OTA amount detected in sparkling wines was 0.44 µg l^?1 (range 0.14–0.71 µg l^?1). Two of 20 must samples contained OTA at low levels (0.08 and 0.18 µg l^?1), while none of 10 grape juice samples contained OTA. Highest amounts of OTA were found in special wines (45%), with a maximum of 15.25 µg l^?1 in a muscatel sample. Copyright © 2004 Society of Chemical Industry     

Ochratoxin A in wine and grape juice sold in Canada.

Ochratoxin A (OTA) was determined in 251 samples of wines and grape juice collected over 3 years in Canada. In total, 25/84 samples of red wine, 22/96 samples of white wine, 3/46 red grape juices and 1/25 white grape juices contained OTA levels above the limit of quantitation (LOQ). Canadian wines, when compared with imported products, showed both a lower OTA occurrence, noted as positive (19 versus 48% above the limit of detection (LOD) for wines), and a lower level of OTA contamination (upper bound mean of 17.5 versus 163pg ml(-1) for wines). Wines from the USA contained no quantifiable levels of ochratoxin A. OTA was found in Canadian and US grape juice samples, with 12.9% above the LOD and an upper bound mean of 13.3pg ml(-1). It was extracted from a wine or grape juice sample by passing it through an immunoaffinity column. The sample matrix was washed off the column with water. OTA was eluted from the column with methanol and quantitatively determined by liquid chromatography using a fluorescence detector. The presence of OTA was confirmed by esterification with boron trifluoride-methanol. The LOQ of OTA was estimated as 20 pg ml(-1) in white wine (S/N 10:1) and 40 pg ml(-1) in red wine, white grape juice and red grape juice (S/N 20.1). The LOD was estimated as 4pgml(-1) for white wine and 8pgml(-1) for red wine and white and red grape juices (S/N 3:1).     

Optimisation of the Amido Black assay for determination of the protein content of grape juices and wines

While the heat/chill stability of white wines cannot be predicted from the total protein concentration, this information is useful in assessing the effectiveness of fining treatments. We have adapted the Amido Black assay for use in grape juice and wine. The response of bovine serum albumin (BSA) was similar in water, model wine and model juice. The linear range of the assay (<100 mg l^?1) extends beyond protein concentrations typically found in grape juices and wines. The limit of quantification was 11.1 mg l^?1 for BSA in model wine and 7.6 mg l^?1 in model juice, while the limit of detection was found to be less than 3 mg l^?1 in either solution. In contrast to other methods of protein determination, this assay is not affected by common wine phenolic and pectic compounds or by glutathione. The mean response of BSA was similar in model juice and red and white grape juices. The mean response of BSA in red wine was lower than in white wine and model wine (p < 0.001), and there was considerable variation in response among wines. Protein concentrations determined using this method were reproducible (CV < 10%). This optimised assay can be used to monitor protein levels in grape juices and wines. © 2001 Society of Chemical Industry     

Occurrence and stability of inorganic and organic arsenic species in wines,rice wines and beers from Central European market

We investigated in total 80 wine samples of different types and seven grape juice and 23 beer samples purchased from markets in Central Europe in order to understand the arsenic (As) speciation and help assess the potential As toxicity via intake of alcoholic beverages. Generally, total As concentrations in most samples investigated were below the drinking water limit 10?µg?l^?1 published by the World Health Organization (WHO); ranging from 0.46 to 21.0?µg?l^?1 As in red and white wines and from 0.75 to 13.4?µg?l^?1 As in beers. In addition, concentrations of total As in rice wine and in rice beer were 0.63–6.07 and 3.69–8.23?µg?l^?1 As, respectively. The total As concentrations in ice wine ranged from 7.94 to 18.8?µg?l^?1 As, significantly higher than in white and red wine. Arsenite predominated as the As species in most of the wine samples, whereas arsenate was the dominant species in rice wine, beer and rice beer. Methyl As components were usually minor components in all wine and beer samples. Monomethylarsonic acid, dimethylarsinic acid and two additional unknown As species were frequently found in grape juice, late harvest and ice wine with higher sweetness. After air exposure, arsenite, arsenate, monomethylarsonic acid and dimethylarsinic acid were stable at 4°C for months, probably due to the acidic conditions of wine and beer samples. The presence of sulfite had little influence on As speciation in wine. Despite the predominance of more toxic arsenite and arsenate in wine and beer, the estimated weekly exposure to As (via consumption of beer, wine and rice wine) is low. The As intake per capita is 6.81?µg from beer, <1.93?µg from wine and 0.88?µg from rice wine, estimated using the median of total As concentration multiplied by the average consumption per capita of the corresponding beverage.     

In‐house validation of a high‐performance liquid chromatography analytical method for quantification of ochratoxin A in unfermented grape juice

A validated high‐performance liquid chromatography (HPLC) method with fluorescence detection for the quantitative analysis of ochratoxin A (OTA) in unfermented grape juice is described. Five millilitres of unfermented grape juice was mixed with 45 mL of PBS, and the pH was adjusted to 7.2. Then the mixture was filtered under vacuum through a glass microfibre filter and cleaned up with immunoaffinity columns prior to analysis by HPLC. Validation of the analytical method was based on the following criteria: selectivity, linearity, limit of detection and quantification, precision (within‐day and between‐day variability) and recovery and uncertainty estimation. Detection and quantification limits obtained were 0.02 µg L^?1 and 0.05 µg L^?1 respectively. The percentage recovery was 91.5% (RSD = 3.9). This method was applied to the measurement of 30 veraison stage unfermented grape juice samples. Copyright © 2007 Society of Chemical Industry     

A survey of ochratoxin A occurence in Greek wines

A total of 150 wines, including 123?dry wines (64 red, 49 white and 10 rosé) and 27 dessert wines (14 red and 13 white), were obtained from various viticulture and oenological practices across Greece during the period 1999–2006 and analyzed for ochratoxin a (OTA) using immunoaffinity clean-up and HPLC with fluorescence detection. There was a high frequency of OTA in commercially available wines (69% positive samples). However, the level of contamination was relatively low, with only one sample marginally reaching the EU permitted maximum level (2.0?µg?l^?1). A total of 91% of the samples had OTA concentrations <1.0?µg?l^?1. The higher concentrations were found in wines from the southern regions, especially in dessert-type wines. There were no significant differences based on wine color or production years. Furthermore, there was no difference between conventional or organic cropping systems in terms of OTA presence.     

Ochratoxin A in wines from 2002 to 2008 harvest marketed in Rio de Janeiro,Brazil

The occurrence of ochratoxin A (OTA) in wine from 2002 to 2008 harvest, traded in Rio de Janeiro State, was evaluated by analysing 43 national and 37 imported wines from Argentina (32) and Chile (5), adding up to 80 samples in total. OTA determination was performed using immunoaffinity columns and high-performance liquid chromatography. In 80 wine samples analysed, 25 (31.3%) were positive, presenting levels greater than 0.020?ng OTA mL^?1. It was not detected in imported wines. Within national wines, 58.1% of the samples were contaminated, with levels ranging from 0.020 to 0.050?ng?mL^?1. The toxin was detected in 18 (69.2%) of 26 samples analysed of red table wine. Wines from 2008 harvest presented 84.6% of samples contaminated in 13 samples analysed. Despite the levels found in this study, they are below Brazilian tolerance limits. Nevertheless, the presence of OTA as found contributes to the human exposure to this toxin.     

Antioxidant activity and phenolic content of wine vinegars produced by two different techniques

BACKGROUND: The presence of phenolics in fruit, red wine and vinegar has positive health effects due to their significant antioxidant activity. The aim of the study was to determine the effects of two different vinegar production methods on antioxidant activity and phenolic level of vinegars derived from Ulugbey Karasi grapes. Traditional surface and industrial submerge methods were used to make vinegar. Samples were taken from fresh red grape juice, maceration, wine, traditional vinegar and industrial vinegar. RESULTS: Total phenolic content of traditional and industrial vinegar samples were 2690 mg L^?1 and 2461 mg L^?1 GAE, respectively. ORAC values of traditional and industrial vinegar samples were 10.50 µmol mL^?1and 8.84 µmol mL^?1 TE, respectively. Antioxidant activity values of traditional and industrial vinegars were 13.50 mmol L^?1 and 10.37 mmol L^?1 TEAC, respectively. Gallic acid, catechin, epicatechin, chlorogenic acid, caffeic acid, syringic acid, p‐coumaric acid and ferulic acid were detected in grape juice, wine and vinegar samples. The content of catechin in industrial vinegar (27.50 mg L^?1) was significantly higher than that of in traditional vinegar (13.76 mg L^?1) (P < 0.05). Traditional vinegar had higher amounts of chlorogenic and syringic acids than the industrial vinegar (P > 0.05). CONCLUSION: Results of this study showed that different production methods affected the functional constituents of wine vinegars. Copyright © 2010 Society of Chemical Industry     

Ochratoxin A: an improvement clean-up and HPLC method used to investigate wine and grape juice on the Polish market.

A routine method appropriate for the determination of ochratoxin A (OTA) in wine, grape juice and grape juice drinks was described, and the occurrence of the mycotoxin was investigated in the most popular red wines, grape juice and grape juice drinks available on the Polish market. After clean-up on immunoaffinity column, samples were analysed by RP-HPLC using a fluorescence detector at 330 and 460 nm. The average OTA recoveries from spiked blank wine samples varied from 60 to 82%, and RSD% ranged from 5 to 14%. The OTA recovery for spiked grape juice and grape juice drinks were 80-100%, but the RSD% was between 7 and 10%. The limit of detection and limit of quantitation for all sample types were 0.5 and 2.0 ng l(-1), respectively. Fifty-three samples of red wine and seven samples of grape juice and grape drinks were assessed by means of this analytical procedure. OTA was detected in most wine samples (92%); its concentrations ranged from 2.2 to 6710 ng l(-1). In all grape juice and drink samples, OTA levels ranged from 1.6 to 64.7 ng l(-1).     

Occurrence of ochratoxin A in wine and grape juice marketed in Rio de Janeiro, Brazil.

Ochratoxin A (OA) is receiving attention world-wide because of the hazard it poses to human health. The aim was to test the distribution of OA in grape juice, pulps of frozen grapes, and national and imported table wine obtained from markets in Rio de Janeiro, Brazil. Analytical methodology using immunoaffinity column for OA extraction and clean-up with a final separation on a reversed-phase (C(18)) column and fluorescence detection in high-performance liquid chromatography showed a detection limit of 21 ng l(-1). The mean recovery was 91% for red wines and 82% for white wines; while the mean recoveries for juices and pulps of frozen grapes were 91.6 and 88%, respectively. Of 64 samples of grape juice and frozen pulps, 25% were positive for OA, being the mean content of 37 ng l(-1) with a maximum concentration of 100 ng l(-1). In wines, the mean concentration detected in 80 samples analysed was 34.4 ng l(-1) with 28.75% of positive samples. Red wines showed the highest percentages and levels of contaminated samples: 38% and 37 ng l(-1), respectively. The white wine contained levels above 26 ng l(-1) in 17.75% of the analysed samples. The levels of contamination detected in red wine sold in Río de Janeiro were not enough to surpass the virtually safe dose established as 5 n g kg(-1) body weight of daily intake.     

Occurrence of ochratoxin A in wine and ochratoxigenic mycoflora in grapes and dried vine fruits in South America

Grape and wine production in South America represents about 6.6% and 10% respectively of the world grape and wine production. The available information on the ochratoxigenic mycoflora and ochratoxin A (OTA) presence in wine grapes, wines, grape juices and dried vine fruits is limited. Surveys have been carried out in Argentina and Brazil which showed that Aspergillus niger aggregate are predominant in the Argentinean varieties while from the Brazilian varieties the species A. niger, Aspergillus ochraceus and Aspergillus carbonarius were isolated. A mycobiota survey from wine grapes in Argentina showed that while Alternaria alternata was predominant, Aspergillus section Nigri species were isolated from 60% of samples. About 41% of black Aspergilli isolates produced OTA with levels ranging from 2 to 24.5 ng mL(-1). In another study, about 83% of A. carbonarius isolates from dried vine fruits produced OTA, with levels ranging from 2 to 5200 ng mL(-1). A survey of grape juices and wines of Brazilian, Argentinean and Chilean origin were found to contain very low levels of OTA. Studies are in progress in Latin America on the ecophysiology of ochratoxigenic fungi and OTA occurrence to reduce the impact of this toxin in the food chain.     

Anthocyanin profile in berry skins and fermenting must/wine, as affected by grape ripeness level of Vitis vinifera cv. Shiraz/R99

The release of anthocyanin compounds from berry skins into the wine is affected by several viticulture and oenological practices. Ripeness level seems to play a significant role. The study aimed to evaluate the extraction kinetics of individual anthocyanins from grape skins into wine under controlled conditions of small-scale vinification of Shiraz grapes, harvested at three ripeness levels (23, 25 and 28°Brix). The anthocyanin profile of intact berry skins, fermenting musts/wines and crushed skins during the period between crushing and pressing was analysed by HPLC. Ripeness level greatly impacted on the skin?/?juice ratio (ranging from 169?± 4.5?g?L^?1 at 23°B, 185?±?7.2?g?L^?1 at 25°B and 256?±?10.7?g?L^?1 at 28°B) and on grape anthocyanin concentration (ranging from 0.80?±?0.13?g?kg^?1 at 23°B, 0.78?±?0.07?g?kg^?1 at 25°B and 1.21?±?0.13?g?kg^?1 at 28°B) and profile (%) at harvest. In addition, it affected the rate and amount of individual anthocyanin extraction from skins into wine and their transformation during fermentation, consistent with the relevant chemical group classification (3-glucoside, 3-acetyl-glucoside, 3-p-coumaroyl-glucoside). At pressing, the anthocyanin concentration of the three wines was similar (319?mg?L^?1, on average), but the anthocyanin profile was different, particularly the ratio of 3-glucoside?/?3-p-coumaroyl-glucoside derivatives, which was on average 3.55 at 23°B and 25°B and 2.6 at 28°B. Viticultural choices, such as to harvest earlier or later, influencing the chemical and physical composition of the berries, may influence the extraction kinetics of individual anthocyanins and their destiny in the fermenting must, offering to winemakers different basic wines suitable for the production of different wine products. These findings are valuable to improve viticultural and oenological practices for Shiraz wine production, allowing the improvement of wine quality and the purposeful creation of different styles of wine.     

A survey of ochratoxin A contamination in feeds and sera from organic and standard swine farms in northwest Italy

BACKGROUND: A survey was carried out on conventional (n = 11) and organic (n = 4) swine farms in northwest Italy in order to investigate the occurrence of ochratoxin A (OTA) in feed and serum samples collected from September 2006 to March 2009. Each farm was sampled twice and a total of 30 feed samples and 285 serum samples were collected. OTA levels were determined through extraction, immunoaffinity column purification and high‐performance liquid chromatography analysis coupled with fluorimetric detection. RESULTS: All feed samples resulted to be contaminated with OTA at levels ranging from 0.22 to 38.4 µg kg^?1. The OTA concentrations found in organic feed samples were significantly higher (P < 0.05) than those found in conventional feed samples. All serum samples resulted to be contaminated with OTA at levels ranging from 0.03 to 6.24 ng mL^?1. The OTA concentrations found in organic serum samples were significantly higher (P < 0.001) than those found in conventional serum samples. CONCLUSION: None of the feed samples contained more than the maximum level (50 µg OTA kg^?1, considering a feed moisture content of 120 g kg^?1) recommended by the European Commission for OTA in complementary and complete swine feedstuffs. The OTA contamination of organic feed and serum samples was found to be significantly higher than that of conventional feed and serum samples. Copyright © 2010 Society of Chemical Industry     

Analysis of Ochratoxin A in Wine by High-Resolution UHPLC-MS

A method for determination of ochratoxin A (OTA) in wines using a new-solid phase extraction clean-up procedure followed with ultra performance liquid chromatography (UHPLC)-Orbitrap MS based on two scan events (full-scan Fourier transform mass spectrometer [FTMS] and higher energy-induced collision dissociation[HCD] data-dependent MS/MS) in positive ionization mode has been developed. The limit of detection (LOD) was estimated at 0.46 μg l^?1 for white wine, 0.53 and 0.54 μg l^?1 for rosé and red wines, respectively. The limit of quantification (LOQ) was estimated at 1.57 μg l^?1 in white wine, 1.77 and 1.81 μg l^?1 in rosé and red wines. Recovery experiments were carried out with spiked samples at three concentration levels (2, 5 and 10 μg l^?1). The OTA recoveries in spiked white wine samples varied from 69.6 % to 99.8 %, while the recoveries for rosé and red wine samples were in the range of 63.0–110.2 % and 63.6–103.2 %, respectively. Finally, based on the results, it is concluded that the combination of C18 cartridge with conventional particle packed columns and UHPLC LTQ-Orbitrap XL is an appropriate procedure for OTA analysis in wines.     

新疆葡萄酒中赭曲霉毒素A含量分析

赭曲霉毒素A（OTA）是葡萄及其深加工产品中主要的真菌毒素,同时也被国际癌症研究机构（IARC）定为2B类致癌物。 采用 酶联免疫法（ELISA）商业试剂盒对新疆四大产区葡萄酒中OTA含量进行调研分析,研究不同产区葡萄酒中OTA含量的差异;同时, 对不同葡萄品种酿造葡萄酒过程中发酵葡萄汁和葡萄酒的OTA含量进行测定,分析酿造过程中OTA的变化规律。 结果显示,34份葡 萄酒样品中OTA含量均未超过2 μg/L;其中,焉耆盆地和吐哈盆地葡萄酒中OTA含量较低,平均含量分别为0.19 μg/L、0.20 μg/L;在 白葡萄酒酿造过程中OTA含量呈显著的下降趋势,而红葡萄酒酿造中OTA含量呈先升高后降低的趋势。     

Detection of ochratoxin A and cis- and trans-resveratrol in red wines and their musts from Calabria (Italy)

The natural occurrence of ochratoxin A (OTA) and cis- and trans-resveratrols in red wines has been widely reported. The aim of this work was to evaluate the ochratoxin A (OTA) and both cis- and trans-resveratrol content of red wine (from must to wine) in a pilot-scale vinification process in Calabria (Italy). Eleven samples were collected at different stages of vinification and analysis was carried out by HPLC. Wine from manufacturer 3 contained the highest amount of trans-resveratrol (3.41?mg?l^?1). This wine was characterized by an Aglianico–Magliocco grape variety. Interestingly, data regarding OTA showed that the value of this contaminant was low in all analyzed samples and, in each case, below the legal limit (2.0?mg?l^?1 (ppb)). Overall, the results demonstrated the high quality of wines produced in Calabria.     

Ochratoxin A in grape pekmez (grape molasses) consumed in Turkey

In this study, ochratoxin A (OTA) in 55 home-made, 20 commercial and 7 organic grape pekmez (grape molasses) produced in Turkey was investigated. OTA was detected in 73% of home-made pekmez samples, in 35% of commercial pekmez samples and in 71% of organic pekmez samples. Eleven per cent of the samples had OTA levels higher than 10 µg/l. The highest OTA level (31 µg/l) was detected in organic pekmez. The maximum OTA levels were 15 µg/l and 12 µg/l in home-made and commercial pekmez samples, respectively. Mean OTA levels were 3.5 µg/l, 1.4 µg/l and 9.2 µg/l in home-made, commercial and organic pekmez samples, respectively. Organic pekmez samples and home-made pekmez samples had higher OTA contamination than commercial pekmez samples. Results confirm OTA contamination in grape pekmez samples, indicating that the OTA level in grape pekmez could be a potential risk for consumers.     

An overview of ochratoxin A in beer and wine

Ochratoxin A (OTA) is a mycotoxin produced mainly by several fungal species of the genera Aspergillus and Penicillium. This mycotoxin has been shown to be nephrotoxic, hepatotoxic, teratogenic and carcinogenic to animals and has been classified as a possible carcinogen to humans. OTA occurs in a variety of foods, including beer and wine. Reports on OTA occurrence in beer indicate that this is a worldwide problem due to the widespread consumption of this beverage. At present, the European Union (EU) has not set a maximum allowable limit (MAL) for this mycotoxin in beer, although there is a limit in barley and malt. Studies carried out in different countries agree in the high proportion of samples contaminated with OTA although levels are, usually, below 0.2 ng/ml. OTA occurrence has been related to the contamination of malt barley with ochratoxigenic species, particularly Penicillium verrucosum. OTA produced in grains is carried to wort and, although fermentation decreases the concentration, the toxin is not eliminated. Reducing the fungal contamination of malt barley is the most promising strategy for reducing OTA in beer. With regard to wine, surveys on the presence of OTA have been conducted worldwide. The proportion of wines in which OTA is detected is very high (above 50%) in some countries (especially in the Mediterranean basin) although only a few wines contained concentrations exceeding the MAL laid down by the EU (2.0 ng/ml). A gradient of concentration is usually recognized; OTA levels decrease in the order red, rose, and white wine but also with increasing latitude of the producing countries. OTA presence in wines is due to the black aspergilli, mainly A. carbonarius, which can grow on grapes in the vineyards and produce the toxin. At grape crushing, the juice can be contaminated with the toxin which is carried over into wine, where it persists due to its stability. Pre- and post-harvest treatments are being investigated to diminish contamination of wines as much as possible.     

Multitoxin evaluation in fermented beverages and cork stoppers by liquid chromatography–tandem mass spectrometry

A total of twenty‐eight mycotoxins were surveyed in wine (red, white and rose), cider (white and rose) and their cork stoppers from eight countries. Toxins of different fungi genera were detected as follows: Alternaria (ATs: alternariol – AOH; alternariol methyl – AME) and Penicillium/Aspergillus (ochratoxin A – OTA; penicillic acid – PAC). Toxins and levels varied with the sample types and country of origin. Wine presented contamination of OTA, AOH and AME. OTA was detected in forty‐one wine samples with levels ranging from 0.01 to 0.86 μg L^?1, below EU legislation. AOH and AME were detected in thirty‐three and eight of wines samples, respectively, at levels from 0.2 to 13.3 μg L^?1, while no contamination was detected in ciders up to the method LOQs. Regarding the cork stoppers toxins detected, they were AOH, AME and PAC. Corks of red wine from different countries had levels of OAH and AME ranging from 5.0 to 101.0 and 2.5 to 5 μg g^?1, respectively. It is necessary to pay more attention on the corks processing and cork type used in the bottles as, different from the ordinary ones, the ground bark and compressed type did not have toxins detected.     

Ochratoxin A in beverages from Morocco: a preliminary survey

In a preliminary study, samples of Moroccan wines (n = 30), beers (n = 5) and fruit juices (n = 14) were assayed for ochratoxin A (OTA) by HPLC with fluorimetric detection, followed by confirmation by cleavage of the OTA molecule using carboxypeptidase with HPLC-fluorimetric determination of ochratoxin alpha (OT alpha). All the wine samples were contaminated, and the overall median OTA concentration was 0.65 microg/l (range 0.028-3.24 microg/l). One of the 14 samples of fruit juices was contaminated with a concentration of 1.16 microg/l, whereas none of the five beer samples was contaminated. This is the first report on the occurrence of OTA in various beverages from Morocco.