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Aims:The aim of this work was to verify the influence of mechanical harvesting and postharvest treatments on wine composition. Methods and results:Trials were carried out in triplicate on cv. Montuni grapes. The estimated best setting frequency for the mechanical harvester was 410 shakes/min. Comparing hand-picked and mechanically harvested grapes, the reduced extract and pH results were lower for the hand-picked grapes, showing a more evident berry breakage caused by the mechanical harvester. The wines obtained from mechanically harvested grapes had a lower phenolic compound content than wines produced with hand-picked grapes, indicating that oxidation phenomena occurred; the trend for postharvest treated grapes was different. The significantly lower amount of higher alcohols in the hand-picked grapes trial than in the mechanically harvested ones could be explained by a lower amount of their precursors and oxygen in musts. The sensory differences among the trials were significant for some parameters, but an overall view of the data suggested that the differences were not remarkable and all the wines were good. Conclusion:Postharvest treatments reduce the loss of natural antioxidant compounds found in wines produced from mechanically harvested grapes. Mechanical harvesting does not have a negative influence on wine composition if matched with the proper vineyard characteristics, machine settings and postharvest treatments. The typicality of Montuni wine is maintained in the cases of grapes harvested mechanically with, but also without, any postharvest treatment. The use of these treatments is otherwise useful to obtain wines with a better stability.Significance and impact of the study: With respect to mechanical harvesting, this study highlights the importance of maintaining and/or improving the quality of mechanically harvested grapes containing the harvesting costs. Conclusion :Les traitements après vendange réduisent la perte des composés antioxydants naturels dans les vins issus de raisins récoltés mécaniquement. La vendange mécanique n'a pas une influence négative sur la composition des vins, si on prend en compte les caractéristiques du vignoble, les réglages de la machine à vendanger ainsi que les traitements après la vendange. La typicité du vin issu du cépage Montuni est conservée dans le cas de vendanges mécaniques, avec, mais aussi sans, traitements après vendange. L'usage de ces traitements est utile pour obtenir des vins ayant une meilleure stabilité.Signification : Cette étude a souligné l'importance de maintenir et-ou d'améliorer la qualité des raisins récoltés à la machine, en limitant les dépenses liées à la vendange. AbstractRésumé manuscript

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A high-performance liquid chromatographic method is proposed for the simultaneous separation of main carboxylic acids, carbohydrates, ethanol, glycerol, and 5-HMF in beer by direct injection. A column packed with a sulfonated divinyl benzene-styrene copolymer and an isocratic elution with 0.0045N sulfuric acid and acetonitrile (6%, v/v) are employed. UV and refractive index detectors connected in series are also used to reduce the matrix interference of phenolic compounds. In conditions described, nine compounds are quantitated in a single chromatographic run without any pretreatment except for sample dilution and filtration before injection. Precision, accuracy, linearity of response, limit of detection, and limit of quantitation are also evaluated for each compound. Satisfactory results are obtained to justify the application of this method to all phases of beer production for process and quality control.

During the storage of sparkling wine a compound with a λ max of nm gives the major peak in the HPLC-DAD chromatogram at 280 nm (70% of total area). We used liquid chromatography coupled to negative electrospray ionization mass spectrometry with a triple quadrupole and timeof-flight analyzer to elucidate the structure of this compound. The electrospray ionization-mass spectrometry analysis showed two main ions at 177 and 355 m/z. The MS/MS spectrum of the 177 m/z ion showed several ions from losses of H 2 O, CO 2 and CH 2 =CH 2 groups. The time-of-flight analyzer determined an accurate mass of 177.0398. Analysis of the derivatized compound by gas chromatography coupled to mass spectrometry was also performed. A lactone compound was proposed to be used as a marker of ageing in sparkling wines. Keywords: LC/MS, MS/MS, TOF, Accurate mass, GC/MS, Sparkling wine. 1 Introduction Over 222 million bottles of sparkling wine (Cava) were produced in Spain each year, of which more than 58 % were exported. Cava is produced by the second fermentation of a blend of white wines, followed by biological ageing in contact with lees in a closed bottle at 6 atmospheres of CO 2. For premium sparkling wines, the ageing period is between nine months and several years. Although sulphite is added to wine as an anti-oxidant, during storage in a cellar (biological ageing) and/or during distribution, several reactions that involve phenols and sugars lead to wine browning. A number of these reactions may produce compounds of interest to wineries as quality markers. In cava samples subjected to a browning test in our laboratory, we detected various unidentified compounds [1]. One, with a λ max of 284 nm, increased markedly along the test. In the studies of M. Mayén et al. [2], P. Benítez et al. [3], and M.A. Pozo-Bayón et al. [4], about phenolic compounds in wine related to ageing, similar compound was detected. The formation of this compound was related to an increased of browning. The identification of new compounds formed during wine elaboration and storage is difficult. However, data about the molecular structure of these compounds could contribute to our understanding of the formation mechanism and to the identification of precursors. Hyphenated techniques (Liquid or Gas chromatography coupled to Mass spectrometry) are suitable to identify new compounds formed during wine storage. The most common techniques are liquid chromatography-mass spectrometry (LC/ESI-MS) [5, 6, 7, and 8] and tandem mass spectrometry (ESI-MS/MS) [9, 10, and 11]. Triple quadrupole instruments have been widely used for the study of fragmentation pathways in the characterization of analytes with unequivocal assignment of mass fragments. In recent years, a new tool has become available, time-of-flight mass spectrometry (TOFMS), with high selectivity, resolutions of ∼ 10 000 without loss of sensitivity, and high mass accuracy. These techniques are particularly useful for the assignment of elemental composition [12, 13, and 14]. In the current work, we applied LC/ESI-MS, ...