Evaluation of two transmittance meters in estimating chlorophyll and nitrogen concentrations in grapevine cultivars

AIM: The use of non-Saccharomyces (NS) yeasts in multi-starter fermentations with S. cerevisiae is a trend in the wine industry, but the number of strains commercially available in a powder formulation, such as active dry yeasts (ADY), is still limited.

Fungus resistant grape varieties (FRGV or PIWI) offer many benefits such as less pesticide use or premium prices for enhanced sustainability. Still, winemakers are concerned about inferior wine quality. This study evaluates how European wine consumers assess wines made from new FRGVs in comparison to traditional V. vinifera varieties. Most of them were grown in the same vineyard. Four white (Calardis Blanc, Muscaris, Sauvignac, Cabernet Blanc) und three red (Satin Noir, Cabernet Cortis, Laurot) FRGV were compared to Riesling, Sauvignon blanc, Muskateller, Cab. Sauvignon and Merlot. For each FRGV, different styles were vinified using standardized protocols.

Recent EU regulations allow the use of carboxymethylcellulose (CMC) as a stabilization agent in wine. We tested CMC in bases for sparkling wines, which must be stabilized before the second fermentation that raises alcohol concentration by 1,5%.

The concept of terroir in viticulture deals with the influence of environmental factors on vine behaviour and grape ripening. Recent advances in technology, in particular computer technology, allow a more in-depth study of the environment. Geomorphology can be studied with digital Elevation Models (DEM). Soils can be surveyed with geophysics.

The study of anthocyanins in wines and grapes has been the subject of numerous research works over the years due to their important role in enology regarding their contribution to wine sensory properties.