Freeze-thaw treatment to enhance phenolic ripening and tannin oxidation of seeds

The Pomerol vineyard, located 35 km east of Bordeaux, covers around 800 ha on the left bank of the Isle. There is a system of fluvial terraces with more or less coarse gravel and pebble spreading, resting on a Tertiary substratum ranging from the Middle to Upper Eocene to the Lower Oligocene (Dubreuilh, 1993). This interweaving of terraces of varying thickness results in a brutal superposition of differentiated materials which give rise to various types of soil. Several site studies in this sector of the Libounais show significant morphological and analytical differences from one point to another (Guilloux et al ., 1978; Duteau, 1982; Van Leeuwen et al.., 1989). The distribution of the soils of the Pomerol vineyard was studied and resulted in a cartography at 1/25000th (Merouge, 1995).

This study evaluates the effect of microwave treatment in grape maceration on the content of free and glycosidically bound varietal compounds) of must and wine and on the overall aroma of wines produced in the presence and absence of SO2.

For a long time, cool climate grapevine breeding has striven for early ripening cultivars to adapt to the former climate conditions.

Vine clone selection aims at the survival of clones with particularly desireable attributes for the production of high quality wines. The purpose of this research was to study the enological potential of the clones of Greek indigenous grape varieties over two vintages, 2018 and 2019.
METHODS: Two clones of the white grape varieties Moschofilero (E26 and E27), Assyrtiko (E11 and 16), Roditis (25E16 and 02E1E21) and two clones of the red grape varieties Xinomavro (19 and E2E30) and Agiorgitiko (03E40 and 41E47) were vinified under the same protocol for the white wines and common for the red wines in 2018 and 2019. The resulting products were studied for several enological parameters such as alcohol content, volatile acidity, pH, total phenolics, anthocyanins and tannins for the red wines, as well as browning tests for the white wines. The aroma profile of these ten samples was investigated through sensory analysis with intensity rating of individual attributes on a five-point scale by a trained panel.

Wine flavor results on complexes interactions of odorous components, which come from different aromatic families like esters, thiols, aldehydes, pyrazines or lactones.