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 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 […]

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 […]

This discussion is a follow up with our last blog on the 2017 maturation What is the situation end of september? A general disorder in sugar accumulation is observed in northern California. The trend is widespread and shows sluggish sugar accumulation rate across many different vineyards. The extend of the phenomenon indicates […]

Harvest decision 2017: A ripe Cabernet Sauvignon in Napa “should be worth the wait!” We discuss a preliminary analysis of the 2017 vintage effect on berry ripening dynamics. Our main conclusions are synthesized in this short summary below. If you are interested in the rationales and discussion points, please scroll down after the […]

If you read this blog you are probably interested in understanding the complexity of vine response to contrasted environmental conditions. Everyday scientific results shed new light on plant mechanisms which, if they are properly understood, can help the winegrower optimizing his practices. Today, we discuss the relationship between :root temperature, […]