“Only rack with the north wind“
I was listening to this great podcast with Ehren Jordan (whom I also met in the past) and I was interested to hear about his time working in Cornas. At about minute 40, he recollects how he was scolded by a fellow winemaker, an old gentleman, about racking while raining, as racking should never be done in bad weather, but only “with the north wind”.
This approach has a scientific basis and some of it is explained in the podcast, but I tried searching other sources to better understand. I then found this fantastic article which starts from a slightly different point, but gets to the conclusion that I need.
As also stated by Ehren in the podcast, the north wind in Cornas is a high pressure system, it brings good weather. With high pressure the air sinks, even though we may not feel it clearly. We are talking about some 0,0 something of a bar and yet in this situation the air is exerting more pressure on everything, included the wine in your barrel. The carbon dioxide left from fermentation is pushed on the bottom, avoiding bubbles to form in the liquid and lees particles to starting float, which conversely would happen in low pressure systems aka bad weather.
Particles floating means that racking will be less effective. As thus, it is thought better to avoid it during rain and leave it when the sky is clear and the sun shines.
For some reasons I always thought that only grape growing could be organic, not winemaking. WSET Level 2 and Level 3 programs are very precise in limiting the scope of organic philosophy and certifications to the vineyard. The new Diploma material has a brief paragraph about organic winemaking, but I am not sure about the old Unit 2 manual.
So better late than never: recently I finally discovered that EU has a regulation implemented in 2012 precisely defining organic wine and its requirements.
To call our wine organic we must make it from organic grapes. Additionally, some practices like partial dealcoholization or partial concentration through cooling are prohibited, while others (centrifuging, filtering, heating) are permitted under specific conditions. Limits are also set for substances like sulphur dioxide. The annex on the bottom lists what is allowed and to what extend when making wine.
While teaching Level 3 the other day I got a good question from a student. We were tasting an Arboleda Carmenère 2016, from vines grown in Aconcagua Valley. The wine was 13.5% alcohol, medium for WSET standards, but pretty close to the high band. It was also very herbaceous.
So his question was: how can such an alcoholic wine keep such high levels of herbaceousness?
The answer is: because Carmenère. According to this study the concentration of methoxypyrazines in Carmenère is so high that a perceivable herbaceousness is going to remain even when making wine from fully ripe grapes.
Sunlight, timing of rain, employed clone and possibly temperature may influence the rate of methoxypyrazines decrease during ripening and the intensity of this character will vary accordingly. However the value is so high that getting rid of this green bell pepper aroma is probably impossible.