In September 2011, we did a special harvest and micro vinification with part of the Merlot, Cabernet and Syrah. It was a natural, extended whole cluster carbonic maceration.
The experimental fermentation
Natural means nothing added. We counted on wild yeasts and used no sulfites.
Extended means that I let the maceration run for about six weeks. That’s a long time. Especially for a carbonic.
Whole cluster means I left the grapes on the stems.
Carbonic maceration means the tank was completely sealed throughout the maceration so there was virtually no oxygen. The chemical reactions during fermentation result in totally different flavors when there is no oxygen in the environment. Lots of candy like, bubblegummy flavors (often associated with beaujolais nouveau).
Harvest
I previously posted about harvesting the grapes for this micro vinification experiment.
Decuvage
After the six weeks were up, we opened the tank and checked on the grapes. I really had no idea what to expect.
It smelled great and looked like most of the grapes had stayed intact.
We drained juice from the bottom of the tank and took density measurements to see how much sugar was left. It turns out that we had almost finished fermentation on the free running juice. It was at .999 the density of water. Almost! Tasted great. This was definitely killer wine. The grapes also tasted delicious. I froze some for use in cooking recipes later this winter.
Once we drained all the free running juice, it was time to tip the tank over and scoop out all the remaining grapes into a vertical wooden press. So many of the grapes were still intact, the entire fermentation happening INSIDE the grape. When I would reach in with the bucket, I would hear lots of popping noises as my fingers pressed into the grapes. It was like wine-scented bubble wrap. PS somebody should make wine scented bubble wrap.
I pressed the grapes. This juice was slightly sweeter/denser. It’s clear the fermentation stuck. Such is life. I guess I’m supposed to restart it with a tete de cuve (when you make a little bit of the juice ferment and then double it in size after a day and double it in size again after another day and so on until you get the whole container). But the amount of juice we got is pathetically small (maybe 2 hectoliters / not even a barrel). So a tete de cuve on this would be like a glass of wine. And then the next day a bottle. And then maybe a jug. 
We’ll see.
All the photos of our decuvage
