Comparison of tannin analysis by protein precipitation and normal-phase HPLC

Winter pruning is today the longest operation for hand workers in the vineyard. Over the last years, mechanical pruning practices have become popular in southern France vineyards to respond to competitiveness issue especially for the basic and mid-range wine production. Wine farmers have developed different vineyard management techniques associated with mechanical winter pruning. They sought to be precise or not to control the buds number per vine.

Climate change is modifying environmental conditions in all wine-growing areas of the
world.

Cu organic acid complexes efficiently bind hydrogen sulfide in wine and therefore prevent its accumulation and subsequent reductive off-flavour [1]. This fraction of Cu can also bind methanethiol

Valpolicella is a wine region characterized by a wide use of the technology of grape drying for the production of two red passito wines, recognized as PDOs, “Recioto della Valpolicella” and the most famous “Amarone della Valpolicella”. Geographical origin of the grapes can influence wine composition by grape chemical composition yeast behaviour during fermentation. This study investigates the impact of different commercial yeast strains on aroma profiles of wines produced with withered grapes of different origins. In addition, the influence of spontaneous fermentation is also considered. METHODS: Experimental red wines were produced with a standard winemaking protocol with withered Corvina and Corvinone grapes obtained from two different geographical areas within the Valpolicella region. Fermentations were carried out with four different commercial yeasts plus a spontaneous fermentation. Wines were analysed by means of SPE- and SPME-GC-MS techniques and sensory analysis (sorting task).

Grape phylloxera (Daktulosphaira vitifoliae Fitch), a monophagous pest of the grapevine, induces nodosities on the roots through its sap-sucking activity.