A rapid, sensitive and selective analysis method using Ultra High Performance Liquid Chromatography coupled to triple-quadrupole Mass Spectrometry (UHPLC-QqQ-MS) has been developed for the quantification of polyphenols in rosé wines. The compound detection being based on specific MS transitions in Multiple Reaction Monitoring (MRM) mode, the present method allows the selective quantification of up to 152 phenolic and two additional non-phenolic wine compounds in 30 min without sample purification or pre-concentration, even at low concentration levels. This method was repeatably applied to a set of 12 rosé wines and thus proved to be suitable for high-throughput and large-scale metabolomics studies.

Effects of neutralization on butadiene–methacrylic acid copolymers have been studied. In Hycar CTB with 2% acid groups, small‐angle x‐ray scattering gives evidence of some cation clustering and leads to a value of the mean radius of 5.6 Å for the clusters and a value of the distance between them of 70 Å. When the concentration of salt is increased there is no appreciable change in the distance between clusters or in their size, but their number increases. The structure of clusters has been studied by electron paramagnetic resonance in copolymers neutralized with copper salts. The appearance of a line as in the monohydrated acetate salt permits one to define the structure of clusters consisting of two Cu2+ and four RCOO− ions with two H2O or RCOOH molecules. When the temperature is increased, the signal corresponding to Cu2+–Cu2+ pairs disappears. In high molecular weight butadiene methacrylic acid copolymers with 9% acid groups, we have found the ion pair clusters gathered into larger clusters. In dynamic mechanical properties, a relaxation peak appears at 340°K. We interpret this as due to breaking and possible re‐forming of dipolar associations.

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The color of rosé wines is extremely diverse and a key element in their marketing. It is due to the presence of anthocyanins and of additional pigments derived from them and from other wine constituents. To explore the pigment composition and determine its links with color, 268 commercial rosé wines were analysed. The concentration of 125 polyphenolic compounds was determined by a targeted metabolomics approach using ultra high-performance liquid chromatography coupled to triple quadrupole mass spectrometry (UHPLC-QqQ-MS) analysis in the Multiple Reaction Monitoring (MRM) mode and the color characterised by spectrophotometry and CieLab parameters. Chemometrics analysis of the composition and color data showed that although color intensity is primarily determined by polyphenol extraction (especially anthocyanins and flavanols) from the grapes, different color styles correspond to different pigment compositions. The salmon shade of light rosé wines is mostly due to pyranoanthocyanin pigments, resulting from reactions of anthocyanins with phenolic acids and pyruvic acid, a yeast metabolite. Redness of intermediate color wines is related to anthocyanins and carboxypoyranoanthocyanins and that of dark rosé wines to products of anthocyanin reactions with flavanols while yellowness of these wines is associated to oxidation.

The widespread use of chlordecone (CLD), an organochlorine pesticide, until the 1990s to protect banana crops in the French West Indies led to significant pollution of water and soil and, subsequently, of bovine intended for human consumption. Carcasses are submitted to official controls based on perirenal fat CLD determination. In order to allow for pre-slaughter controls, a selective analytical method based on a molecularly imprinted polymer (MIP) associated to the LC/MS-MS method was developed to determine the level of CLD in bovine serum that can be collected before slaughter. Different synthesis conditions were therefore assayed by varying the nature of the monomer and of the porogen, and the most promising MIP in terms of selective retention for CLD (extraction recovery close to 100%) was completely characterized by solid-phase extraction (repeatability of the extraction procedure, of the synthesis, and of the cartridge filling) in pure medium. The capacity of the MIP was determined at 0.13 µmol g−1 of MIP. After application of a spiked bovine serum sample on the MIP, the selective retention was maintained (87 and 21%, respectively, on the MIP and on the corresponding non-imprinted polymer). Moreover, extraction on the MIP led to a cleaner extract compared to those issued from a conventional C18 sorbent.

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