Ecology and technological capability of lactic acid bacteria isolated during Grillo grape vinification in the Marsala production area.

Grapes of “Grillo” variety, used to produce Marsala wine, were harvested from five vineyards different for climatic and agronomic parameters, in order to obtain a first mapping of lactic acid bacteria (LAB) inhabiting the production area. Marsala base wine production was followed at large-scale and two experimental vinifications, different for lysozyme and SO2 concentration and combination, were carried out at pilot-plant scale. LAB communities and conventional chemical parameters were periodically analysed. LAB were found on grapes at an average concentration of about 102 CFU g-1 which decreased during the transformation process. A total of 146 colonies were collected, but only 35 were recognized as presumptive LAB. On the basis of phenotypic differences and isolation source, 16 isolates were then subjected to genotypic identification and gathered into the following species: Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Enterococcus faecium, Leuconostoc fallax and Sporalactobacillus nakayamae subsp. nakayamae. Lactococcus lactis subsp. lactis strains was the species most frequently isolated during winemaking showing the highest resistance to SO2 and lysozyme

Impact of volatile phenols and their precursors on wine quality and control measures of Brettanomyces/Dekkera yeasts

Volatile phenols are aromatic compounds and one of the key molecules responsible for olfactory defects in wine. The yeast genus Brettanomyces is the only major microorganism that has the ability to covert hydroxycinnamic acids into important levels of these compounds, especially 4-ethylphenol and 4-ethylguaiacol, in red wine. When 4-ethylphenols reach concentrations greater than the sensory threshold, all wine’s organoleptic characteristics might be influenced or damaged. The aim of this literature review is to provide a better understanding of the physicochemical, biochemical, and metabolic factors that are related to the levels of p-coumaric acid and volatile phenols in wine. Then, this work summarizes the different methods used for controlling the presence of Brettanomyces in wine and the production of ethylphenols

Binding energies of ground and isomeric states in neutron-rich ruthenium isotopes: measurements at JYFLTRAP and comparison to theory

We report on precision mass measurements of $^{113,115,117}$Ru performed with the JYFLTRAP double Penning trap mass spectrometer at the Accelerator Laboratory of University of Jyv\"askyl\"a. The phase-imaging ion-cyclotron-resonance technique was used to resolve the ground and isomeric states in $^{113,115}$Ru and enabled for the first time a measurement of the isomer excitation energies, $E_x(^{113}$Ru$^{m})=100.5(8)$ keV and $E_x(^{115}$Ru$^{m})=129(5)$ keV. The ground state of $^{117}$Ru was measured using the time-of-flight ion-cyclotron-resonance technique. The new mass-excess value for $^{117}$Ru is around 36 keV lower and 7 times more precise than the previous literature value. With the more precise ground-state mass values, the evolution of the two-neutron separation energies is further constrained and a similar trend as predicted by the BSkG1 model is obtained up to the neutron number $N=71$.Comment: 12 pages, 9 figures, submitted to Physical Review

Beta decay of the Tz=-2 nucleus 64Se and its descendants

International audience; The beta decay of the Tz=-2 nucleus 64Se has been studied in a fragmentation reaction at RIKEN-Nishina Center. 64Se is the heavies Tz=-2 nucleus that decays to bound states in the daughter nucleus and the heaviest case where the mirror reaction 64Zn(3He,t)64Ga on the Tz=+2 64Zn stable target exists and can be compared. Beta-delayed gamma and proton radiation is reported for the 64Se and 64As cases. New levels have been observed in 64As, 64Ge (N=Z), 63Ge and 63Ga. The associated T1/2 values have been obtained

Indirect measurements of neutron-induced reaction cross sections at storage rings

Neutron-induced reaction cross sections of unstable nuclei are essential for understanding the synthesis of heavy elements in stars. However, their measurement is very difficult due to the radioactivity of the targets involved. We propose to circumvent this problem by using for the first time the surrogate reaction method in inverse kinematics at heavy-ion storage rings. In this contribution, we describe the developments we have done to perform surrogate-reaction studies at the storage rings of GSI/FAIR. In particular, we present the first results of the proof of principle experiment, which we conducted recently at the Experimental Storage Ring (ESR)

De l`utilité de la notion de gouvernance pour analyser les modes de management touristique locaux: l`exemple de la station des Arcs

Les stations de sports d`hiver sont confrontées à de nombreuses incertitudes tant structurelles que conjoncturelles; les modalités de leur gestion constituant un axe important de réflexion dans la plupart des stations. En effet, la loi Montagne de 1985 a conféré aux communes la responsabilité du pilotage des stations; une gestion qu`elles assument ou bien délèguent à des opérateurs privés, par l`intermédiaire de délégations de services publics. Ces choix conduisent à des formes de relations variables entre acteurs privés et publics, et ont souvent opposé deux modèles de management, le «corporate model» et le «community model». Cette communication veut montrer que les situations concrètes se situent plutôt dans un entre-deux, où l`enjeu est plutôt de décrypter le système d`acteurs, les logiques d`action ainsi que les modes de coordination. Dans ce domaine, l`informel compte tout autant que le contenu formel des relations entre acteurs, conduisant à qualifier le mode de gouvernance, c`est-à-dire les «arrangements formels et informels entre intérêts publics et privés, à partir desquels sont prises et mises en oeuvre les décisions» (Le Galès, 1995). Cette imbrication formel-informel a ainsi fortement guidé notre analyse de la station des Arcs en Savoie, où nous soulignerons d`une part, le manque de référentiel commun entre la commune et la SMA, opérateur privé chargé du domaine skiable et d`autre part, la volonté de certaines associations de pousser à renouer un dialogue, préalable à des choix et décisions collectifs. / The ski resorts are confronted with many uncertainties as well structural as of the economic situation ; the nature of their management constituting a significant theme of reflexion in the majority of the resorts. Indeed, the law "Montagne" conferred on the communes the responsibility for the piloting of the stations; a management that the communes assume or delegate to private operators (with delegations of public services). These choices lead to forms of varied relationships between private and public actors and often opposed two models of management, the corporate model and the community model. This paper wants to show that the concrete situations are rather in an middle, where the goal is rather to describe the actors` system, their actions` modalities like their modes of coordination. In this field, the informal accounts very as much as the formal contents of the relations between actors, leading to qualify the formal and informal arrangements between public and private interests, from which are taken and applied the decisions. This overlap formal-informal strongly guided our analysis of the resort of the Arcs in Savoie, where we will underline in one hand, the lack of common reference framework between the commune and the SMA, private operator in charge of the skiable field and in the other hand, the will of certain associations to push to join again a dialogue, precondition to choices and decisions collectives

Malolactic fermentation of wine: study of the influence of some physico-chemical factors by experimental design assays

International audienceThe ability of selected lactic acid bacteria to carry out malolactic fermentation depends on the level of numerous wine characteristics. A Hadamard's experimental matrix was used to determine the main effects of 11 physico-chemical factors on malolactic activity of three Leuconostoc œnos strains and one Lactobacillus plantarum strain. Ethanol had the greatest inhibitory effect on the achievement of malolactic fermentation for all Leuc. œnos strains. An inhibitory effect of the L-malic acid was also found in the operating conditions. These strains show different degrees of sensitivity to pH. One of these strains was inhibited by SO2. Malolactic activity of the Lact. plantarum strain is mainly affected by a low pH, and this strain is often less efficient than Leuc. œnos strains. This methodology could be used for the selection of strains for malolactic starters. Further work is in progress using factorial design in order to determine the interactions between influential factors