Search results for "liquid"
showing 10 items of 4351 documents
Quantitative determination of sotolon in wines by high-performance liquid chromatography
1993
Sotolon (4,5-dimethyl-3-hydroxy-2(5H)-furanone) is a key flavour compound in the french flor-sherry “Vin jaune”. This compound was determined quantitatively by extraction of 25 ml of wine on a XAD-4 resin, elution with diethyl ether, separation by HPLC on a Lichrospher 100 Diol column, elution with dichloromethane/hexane (60/40) and UV detection at 232 nm. The amount of sotolon in “Vin jaune” (120 to 268 μg/l) was related to the development of the yeast film over a period of 6 years. Only 6 to 51 μg/l were found in the “Vin de paille” which is made with overmaturated grapes of the same Savagnin vine-plant but without development of yeasts, and 80 to 140 μg/l in “Tokai” which are partly grow…
High Performance Liquid Chromatography Analysis of Grape and Wine Polyphenols
2008
Integrating analytical resolutions in non-targeted wine metabolomics
2015
Direct injection Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), and ultra-high performance liquid chromatography coupled to mass spectrometry (UPLC/MS) were combined for the non-targeted analysis of wine metabolites. The unrivalled resolution on mass measurement allowed by the former and the separation ability of isomeric and isobaric substances by the latter, clearly increases the scope of detectable unknown metabolites in wines. Such methodology is illustrated through the comparison of chemical spaces of a young and an older Pinot noir wine. RP and HILIC chromatography could reveal up to five isomers for a given mass, throughout the explored mass range. CHO, CHOS …
Scopolamine analysis in beverages: Bicolorimetric device vs portable nano liquid chromatography
2021
Abstract Scopolamine (SCP) is often involved in sexual assaults and robberies, particularly in recreational environments. Therefore, analytical tools are required for the analysis of this compound amenable for the field. In this work, a sensor for SCP is described based on the entrapment of KMnO4 into polydimethylsiloxane (PDMS). The possibility of using KMnO4 in combination with the reagent 1,2-naphtoquinone-4-sulfonate (NQS) giving a double sensor acting as a bicolorimetric device is also demonstrated. In contact with the sample, the PDMS composite delivers MnO4−, which reacts rapidly with SCP under basic conditions causing a change of the color of the solution that can be related to the …
Expressing forest origins in the chemical composition of cooperage oak woods and corresponding wines by using FTICR-MS.
2008
A non-targeted, ultra-high-resolution mass spectrometric, direct analysis of oak-wood extracts from two species (Quercus robur L. and Quercus petraea Liebl.) from three French forests, and of a wine aged in barrels derived therefrom has been performed to identify families of metabolites that could discriminate both the species and the geographical origin of woods. From 12 T ultra-high-resolution Fourier transform ion cyclotron resonance mass spectra of wood extracts, hundreds of mass signals were identified as possible significant biomarkers of the two species, with phenolic and carbohydrate moieties leading the differentiation between Q. robur and Q. petraea, respectively, as corroborated …
Comparison of different sample treatments for the analysis of ochratoxin A in must, wine and beer by liquid chromatography.
2004
Abstract Ochratoxin A (OTA) is a mycotoxin produced by some species of Aspergillus and Penicillium verrucosum. It has been found in foods and feed all over the world. There is a great concern about OTA because it is nephrotoxic and probably, carcinogenic to humans. Most of analytical methods developed for OTA in wine, beer and other products are based on LC with fluorescence detection (LC–FLD). In the present work, various procedures for extraction and/or clean-up for determination of OTA in musts, wine and beer by LC–FLD were compared: (1) dilution with polyethylen glycol 8000 and NaHCO3 solution and clean-up an on immunoaffinity column (IAC); (2) extraction with chloroform and IAC clean-u…
Concentration of ochratoxin A in wines from supermarkets and stores of Valencian Community (Spain)
2004
Ochratoxin A (OTA) is a mycotoxin produced by fungi species belonging to the genera Aspergillus and Penicillium being isolated in alcoholic beverages. The aim of this work is developed and applied a procedure for the analysis of OTA in wines. An analytical method based on immunoaffinity column (IAC) for clean-up, liquid chromatography with fluorescence detection (LC-FD), and LC-FD after of OTA methylation was used to determine the occurrence of OTA in wines. Recoveries of this mycotoxin spiked to red wines at 0.5 ng/ml level were >90% with an average of relative standards deviations of 4%. Furthermore, 116 wine samples from designation of origin (DO) and three samples from food stores of Va…
The use of core-shell high-performance liquid chromatography column technology to improve biogenic amine quantification in wine
2015
BACKGROUND HPLC column technology has been improved, providing better resolution of closely eluting compounds, better analyte sensitivity, and shorter analysis times. The core-shell technology columns offer a faster analysis through the use of shorter columns without compromising resolution. The aim of this work was to improve the methods for determination of biogenic amines (BAs) in wine using the new HPLC PFP core-shell column technology. RESULTS Two different elution programs were designed to quantify BAs with the core-shell PFP column. Program I flow rate was 2 mL min−1. The total elution time was 10 min. In elution program II, the flow rate was 0.8 mL min−1 and the total elution time w…
Purification method for the isolation of monophosphate nucleotides from Champagne wine and their identification by mass spectrometry
2001
Monophosphate nucleotides are difficult to identify in Champagne wine because they are present in small concentrations in a complex mixture. A method for the isolation, separation and identification of reference compounds, which achieved on average 79% recovery (except for cytidine derivatives), was developed and applied to wine. Some monophosphate nucleotides were then isolated from a Champagne wine aged on lees for 8 years, by ultrafiltration followed by a semi-preparative HPLC step using a strong anion-exchange column. The fraction obtained was subjected to HPLC in a reversed-phase column to remove the salt previously introduced, before identification of compounds by HPLC coupled to a ma…
Applications of liquid chromatography-mass spectrometry for food analysis.
2012
Abstract HPLC–MS applications in the agrifood sector are among the fastest developing fields in science and industry. The present tutorial mini-review briefly describes this analytical methodology: HPLC, UHPLC, nano-HPLC on one hand, mass spectrometry (MS) and tandem mass spectrometry (MS/MS) on the other hand. Analytical results are grouped together based on the type of chemicals analyzed (lipids, carbohydrates, glycoproteins, vitamins, flavonoids, mycotoxins, pesticides, allergens and food additives). Results are also shown for various types of food (ham, cheese, milk, cereals, olive oil and wines). Although it is not an exhaustive list, it illustrates the main current directions of appli…