Agroclimatic characterisation of the Portugese wine denominations of origin using a compound index

Context and purpose of the study. Intra-varietal variability for key physiological and oenologically important traits can be exploit in viticulture following the consistently higher environmental pressure driven by climate change.

Synthetic pesticides are widely used in viticulture to ensure steady harvest quality and quantity. Fungicides are primarily used to control grapevine diseases but insecticides and herbicides are likewise used. Pesticide residues in viticultural areas currently represent a strong societal concern, but may also affect different trophic chains in such areas. In this project we wish to analyse honeybees collected from hives placed in different vineyards, their natural predator (the invasive hornet Vespa velutina), as well as the honey, grape berries, and wines produced.

Analysis of phenolic compounds typically involve spectrophotometric methods as well as liquid chromatography combined with DAD, fluorimetric, or MS detection. However, the complexity of wine phenolic composition generated, in recent years, attention towards other analytical approaches, including those allowing rapid and inexpensive operations. Voltametric AIM Oxidation of white wine phenolics occurs at different stages during winemaking and storage and can have important implications for wine sensory quality. Phenolic compounds, in particular those with a ortho-diphenol moiety, are main target of oxidation in wine. Strategies for the methods are particularly suited for the analysis of oxidizable compounds such as phenolics. The redox-active species can be oxidized and reduced at the electrode, therefore, applications of electrochemistry have been developed both to quantify such species, and to probe wine maturation processes.3 The project on the diversity of Italian wines aims at collecting and analysing large-scale compositional dataset related to Italian white wines.

3-Isobutyl-2-methoxypyrazine (IBMP) is one of the key molecules in wine aroma with a bell pepper aroma and a very low threshold in wine, 1-6 ng/L for white wine and 10-16 ng/L in red wine1. The differences in these thresholds are likely due to IBMP-non volatile matrix interactions. It has indeed been shown that polyphenols may influence the volatility of flavor compounds2. In the present study, we focus on IBMP-polyphenols interactions in relation to volatility and sensory perception in model wine solution. Methods: 1. GC-MS Static Headspace Analysis: Samples were analyzed by Static headspace analysis with an Agilent 7890A gas chromatograph coupled to HP 5975C mass spectrometry detector (Agilent Technologies, Santa Clara, CA, USA).

Un programme de recherche concernant les facteurs naturels et humains des terroirs viticoles a été développé dans le vignoble A.O.C. de l’Anjou, sur une surface d’environ 30.000 Ha