The aim of this study was to compare pesticide residues, copper and biogenic amines concentrations in conventional and organic wines. For each type of wine production, 20 samples were collected. We ...used two multi-residual methods employing GC/MS (92 pesticides) and LC/MS/MS (112 pesticides) detection. Copper residues and biogenic amines were measured by standard FAAS and HPLC methods. We confirmed lower numbers and concentrations of pesticide residues in organic wines. The most frequently determined pesticide was dimethomorph, followed by boscalid, fenhexamid, metalaxyl + metalaxyl-M, iprovalicarb and pyrimethanil. Also, higher levels of copper were observed in the groups of conventional wines. For biogenic amines, we could not confirm a clear trend. It is unacceptable that some pesticide residues in organic wines were detected, which are not allowed in this type of production. Nevertheless, we can confirm the trend of added value in organic wine production in terms of reducing pesticide residues and copper in bottled wines.
-Added value is in organic wine production in terms of pesticides and copper reduction.-Producers should avoid some commonly found pesticide residues in the last sprays.-No significant difference in the occurrence and concentrations of biogenic amines between both groups of wines.
Pesticide residues in vinification process of two white and two red grapevine varieties were monitored during the 2007 vintage. Crushed grapes, cake, must, lees and wine were sampled during the ...vinification process. Additionally, grapes were sampled during the ripening process. All samples were taken in triplicate and analyzed for the presence of 117 pesticides. The pesticide residues were determined by three validated internal analytical methods: the multi-residual GC-MS method (71 pesticides), the multi-residual LC-MS-MS method (45 pesticides) and GC-MS method for the determination of dithiocarbamates (the sum of their concentrations is given as a concentration of carbon disulfide). Boscalid and phosalone were the most persistent pesticides in grapes during ripening. The concentrations of pesticide residues in must and wine were significantly diminished through separations during the solid and liquid phases of the vinification process, particularly the pressing of crushed grapes and wine racking after alcoholic fermentation. The pesticides detected throughout the vinification process were boscalid, cyprodinil, dimethomorph, fenhexamid, metalaxyl and procymidone and their concentrations in the wines were 0.01–0.02, 0.04, 0.01–0.08, 0.12–0.13, 0.09–0.11 and 0.07–0.13
mg
L
−1 respectively.
In the study we determined the pesticide residues and microbiological quality of bottled wines. Pesticide residues in wine were analysed using the multiresidual method with GC–MS, the multiresidual ...method with LC–MS–MS and the method for determination of dithiocarbamate residues with GC–MS. Furthermore, the effect of bentonite and the combined fining agent on the concentration of boscalid in wine was tested. The microbiological analysis was performed using membrane filtration. Nine pesticide residues were determined in the samples. More than 50% of wines belonged to the category of wines with only up to two pesticide residues. The most frequently determined pesticide in wines was boscalid (76% of samples) followed by fenhexamid (44%). The highest concentrations of pesticide residues in wines were determined for cyprodinil (0.44
mg/L) and fludioxonil (0.21
mg/L). The combined fining agent was more efficient in lowering the concentration of boscalid in wine if compared with bentonite. The results of microbiological quality indicate that no less than one quarter of bottled wines on our store shelves is microbiologically unstable.
The development and accumulation of secondary metabolites in grapes determine wine color, taste, and aroma. This study aimed to investigate the effect of leaf removal before flowering, a practice ...recently introduced to reduce cluster compactness and Botrytis rot, on anthocyanin, tannin, and methoxypyrazine concentrations in ‘Merlot’ grapes and wines. Leaf removal before flowering was compared with leaf removal after flowering and an untreated control. No effects on tannin and anthocyanin concentrations in grapes were observed. Both treatments reduced levels of 3-isobutyl-2-methoxypyrazine (IBMP) in the grapes and the derived wines, although the after-flowering treatment did so to a greater degree in the fruit specifically. Leaf removal before flowering can be used to reduce cluster compactness, Botrytis rot, and grape and wine IBMP concentration and to improve wine color intensity but at the expense of cluster weight and vine yield. Leaf removal after flowering accomplishes essentially the same results without loss of yield.
Grape berries were classified according to diameter and total soluble solids (TSS) to study the effect of light and temperature on methoxypyrazines (MPs), glutathione (GSH), and hydroxycinnamates ...(HCAs) during the ripening of Sauvignon blanc. The light exposure of the fruiting zone was modified within leaf and lateral removal at the phenological stage berry of peppercorn size and no removal (control). In comparison to the control, the concentration of 3-isobutyl-2-methoxypyrazine (IBMP) was below the limit of detection in leaf removal 2 weeks before harvest. Leaf removal had no significant influence on GSH and HCAs in the grape juice at harvest. Berry diameter significantly influenced the concentration of IBMP in the grape juice and did not influence the concentration of GSH and HCAs. At harvest, the concentrations of IBMP in grape juices of similar TSS in the control were 12.6 and 5.2 ng/L in 15.5 and 13.5 mm berry diameter classes, respectively. Furthermore, the study showed that berries of the same diameter were not at the same physiological ripening level (not the same TSS).
Four analytical methods were developed and validated for the determination of veterinary drug residues and environmental pesticide residues in honey: (a) GC-MS method for the analysis of amitraz and ...all metabolites containing the 2,4-dimethylaniline moiety; (b) GC-MS method for the analysis of thymol, chlorfenvinphos and coumaphos; (c) GC-MS method for the analysis of 75 active substances; (d) LC-MS/MS method for the analysis of 60 active substances. Between the GC-MS (method c) and the LC-MS/MS method (method d) there was no overlap among active substances, meaning that using both methods 135 active substances originating from the environment in total were included and validated. The first method involved hydrolysis of amitraz and its metabolites containing the 2,4-dimethylaniline moiety to 2,4-dimethylaniline and extraction of 2,4-dimethylaniline to n-hexane. The other three methods had the same extraction procedure with a mixture of solvents: acetone, dichloromethane and petroleum ether. All 4 methods were tested in practice. Sixty samples of honey were analysed: 22 from organic and 38 from conventional production. Overall, residues were mainly higher than reported in literature but did not exceed MRLs. Risk assessment confirmed that the analysed samples are of no cause for concern for consumers.
The production system, especially fertilisation has an important effect on yield and quality of strawberries. In the present study, plants were fertilized with different doses of nitrogen (0–100% ...recommended doses), calcium chelate, as well as nano fertilizer Lithovit. Strawberry cultivar ‘Clery’ yield and quality parameters (fruit color and firmness) including nutritional indicators (total soluble solids, sugars, organic acids, phenolic and volatile compounds) were monitored. Volatiles were identified and monitored using headspace solid phase microextraction and analysed using gas chromatograph-mass spectrometry (SPME/GC-MS) and sugars, organic acids, and phenolic compounds with high performance liquid chromatography. Organic acids and phenolic compounds were detected with mass spectrometer (HPLC/MS). Both nitrogen and calcium fertilisation had altered sugars, organic acids, volatile and phenolic contents in strawberry fruits. Fertilisation with higher doses of nitrogen and calcium increased the content of unpleasant aromas aldehydes hexanal (up to 3.8-fold) and (E)-2-hexen-1- (up to 3.7-fold). The content of fruity esters was uppermost in fruits fertilised with nano-fertiliser Lithovit (up to 2.3-fold). Fertilisation with N and Ca decreased the strength of ketone and terpenoids fruity aroma. The highest content of total phenols, as well as all individual hydroxycinnamic and hydroxybenzoic acid derivatives were obtained in the nano-fertiliser Lithovit treatment. Fertilisation, especially with nitrogen, had mostly negative impact on strawberry flavour while nano-fertilization with Lithovit improved strawberry phenolic content and aroma.
Wine aroma is influenced by a number of volatile compounds. This article describes the validation of the method for 26 volatile compounds found in wine. Volatile compounds were determined with ...discontinuous liquid-liquid extraction and GC-MS detection. It was determined, that the method is linear with square correlation coefficient ranging from 0.961 to 0.999. Limits of quantitative determination range from 0.52 μg/L to 14.8 μg/L. Recoveries range from 71.1% to 105.7% except for two compounds with lower recoveries. Measurement uncertainty ranges from 5.0% to 28.9%. According to the validation, the method is suitable for the determination of at least 24 volatile compounds common to wine. A practical method application was presented on Zelen wine variety from two different production procedures.
Na aromo vina vplivajo številne hlapne spojine. Ta članek opisuje validacijo metode za 26 hlapnih spojin, ki jih najdemo v vinu. Hlapne spojine so bile določene z diskontinuirano ekstrakcijo tekoče-tekoče in GC-MS detekcijo. Določili smo, da je metoda linearna, z razponom kvadrata korelacijskega koeficienta od 0,961 do 0,999. Meje kvantitativne določitve imajo razpon od 0,52 μg/L do 14,8 μg/L. Izkoristki imajo razpon od 71,1% do 105,7%, razen za dve spojini, katerih izkoristek je nižji. Merilna negotovost ima razpon od 5,0% do 28,9%. Z ozirom na validacijo lahko potrdimo primernost metode za določanje vsaj 24 hlapnih spojin značilnih za vino. Praktični prikaz uporabe metode smo predstavili na vinih sorte Zelen iz dveh različnih postopkov pridelave.
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