Étude des relations sol-vigne sur le vignoble de Côte Rôtie

Gum arabic is composed of a polysaccharide rich in galactose and arabinose along with a small protein fraction [1, 2], which gives its stabilizing power with respect to the coloring substances or tartaric precipitation of bottled wine. It is a gummy exudation from Acacia trees; the products used in enology have two possible botanical origins, i.e. Acacia seyal and Acacia senegal, with different chemical-physical features and consequently different technological effects on wines. The aim of this work is to evaluate the feasibility of discrimination of commercial gums Arabic between their two different sources, on the basis of the absorption of the Fourier Transform Infrared (FT-IR) spectra of their aqueous solutions, in order to propose an extremely rapid and cost-saving method for quality control laboratories.

Cette recherche a eu pour but l’étude des effets d’un renforcement radiatif et thermique sur les zones inférieures de la canopée de la vigne (solarisation par des films ou des paillages réfléchissants installés sur le sol, sous les ceps), notamment l’étude de leurs conséquences sur la composition biochimique des moûts à la vendange et sur la qualité des vins.

Recent studies have demonstrated the role of certain lactones, particularly 2-nonen-4-olide, and volatile thiols (3-sulfanylhexan-1-ol) in the over ripped aromas of noble rot sweet wines (Stamatopoulos et al. 2014ab). These compounds are partly formed during the maturation and under the activity of B. cinerea on grapes. This research was carried out in the vineyard of Sauternes with aim to better understand their genesis depending on the grape over-ripening on two different soil types during 3 vintages. Thus, the study was conducted, with the Sémillon grape, during vintages 2012, 2014 & 2015, at 4 stages of over-maturation of the grapes (healthy, pourri plein, pourri roti, pourri roti + 15 days) considering two vineyard plots with different soil characteristics (calcosol & peyrosol) planted with the 315 Sémillon clone and grafted on 101-14 rootstock respectively in 1981 and 1980 and cultivated with the same vineyard management. Volatile lactones were assayed by liquid-liquid extraction followed by GC/MS analysis and the precursors of 3-sulfanylhexanol by an adaptation of the method by Capone et al. 2010 (SPE-
UPLC/FTMS).

A method of suspect screening analysis to study grape metabolomics, was developed [1]. By performing ultra-high performance liquid chromatography (UHPLC) – high-resolution mass spectrometry (HRMS) analysis of the grape extract, averaging 320-450 putative grape compounds are identified which include mainly polyphenols. Identification of metabolites is performed by a new HRMS-database of putative grape and wine compounds expressly constructed (GrapeMetabolomics) which currently includes around 1,100 entries.

There are fundamentally two different ways in which indications of geographical origin (igos) can be protected. The us approach favors the pre-existing trademark system through collective marks (cms), while the eu approach favors a maximalist approach via a sui generis system which promotes appellations of origin (aos). A consensus however emerges regarding the fundamental protection of origin against misleading, confusing and dilutive uses. Previous literature discusses these competing igo logics from historical, legal and international trade perspectives. In this paper, we depart from the field of social sciences, in particular from recent advancements in the well-established literature on proximities, in order to provide a reflection on the different logics underpinning the aos and cms systems.