We are wrapping up the summary of the 2017 Vintage report with the last session focussing on Phenolic extraction presented by Federico Casassa. Overview of phenolic extraction into red wines: a cellular perspective Continuing on the theme of fruit ripening and fruit maturity from our previous article, the Vintage Report’s […]
Continuing with the 2017 Napa Vintage Report presentation summaries, today’s article is focused on winegrape phenology with Elizabeth M. Wolkovich, and ripening dynamics with Nicolas Bernard. Modeling the future of winegrape phenology As the second scientific speaker following the keynote address at the Napa Vintage Report, Elizabeth M. Wolkovich, Assistant Professor, Department of Organismic […]
The goal of the swiss study presented by Dr Zufferey was to investigate the impact of water stress on vine hydraulics, berry composition and wine quality. Context: how well can Pinot Noir sustain drought conditions ? Combined effect of climatic trends associated with vineyard topography can lead to severe drought […]
What is the relationship between fruit color and wine color concentration? A strong, positive relationship exists between anthocyanin (i.e. color) concentration in grape and in wine (source). However, all anthocyanins accumulated in the skin are not completely extracted into the wine. For that reason, even if a relationship exists, the total amount of anthocyanins extracted […]
In this blog we discuss why berry sugar monitoring is important beyond sugar concentration. Changes in sugar accumulation reflect other chemical changes As berries accumulate sugars, the vine reaches the ultimate stages of its season cycle. Once a maximal amount of sugar per berry has been accumulated, complex chemical changes occurs […]
In this blog we discuss why adapting harvest date to a warming environment is challenging …and why you may not have to trade off sugar concentration to get high color concentration. Higher sugar concentrations at harvest are often associated with an increase in temperature. This is observed empirically and scientifically in the […]
More technical questions regarding volatile phenols management have been asked as the last grapes from 2017 get harvested in Northern California. In this blog post we discuss the limitations attached to current analytical methods and how to make the best of it. Why is it difficult to assess the risk […]
We received a large number of requests asking for practical information and scientific articles on making wine with smoke tainted grapes. Considering the devastation caused by northern California fires, we decided to share all the information we have collected regarding the effects of smoke on grapes and wine. We hope this note will provide some helpful hints […]
The Cool Night Index The Cool Night Index was created to study nocturnal conditions of grapes ripening according to the different wine-making regions (Tonietto, 1999 ; Tonietto et Carbonneau, 2004). By convention, this index is also called nycthermal index and is equivalent in the North Hemisphere to the minimum temperature […]
As the 2017 vintage winds down, I have been thinking about the inclination of the human brain to simplify and generalize. I have noticed this tendency in the way we make many of the crucial decisions in quality winegrowing. We become fixated on one pet parameter and try to use […]
