Well, it’s been a little quiet the past month – at the end of October, once the wine had been racked off the gross lees (the dead yeast cells) I did a bentonite addition. Bentonite is essentially a specific type of naturally occurring clay. When dispersed in wine the clay particles end up with electrical charges on the particles which attract many of the small sediments floating in the wine, grabbing on to them… and then the heavy clay particles sink, and accumulate on the bottom of the tank with all the sediment they could grab attached.
The biggest problem with bentonite is that it can be challenging to rack the clean wine off of it. So part two of the process is to time the bentonite right before you plan to cold stabilize the wine. Which we accomplished handily this year having the outdoor temperatures dip down to minus 6 a couple of times over the past few weeks. The cold temperatures cause tartrate crystals (from tartaric acid which occurs naturally in grape juice) to form, which then accumulate on top of the bentonite. This layer of hard crystals essentially locks the bentonite under a layer of hard material, and enables easy racking. We rely on mother nature as our cooling mechanism – it’s much more environmentally friendly then running chillers (which use ozone depleting refridgerants) – although you can’t always predict when the temperatures will hit the targets. This year we have been really lucky and the cold weather came right when we wanted it to.
So the wine is now fined with bentonite, and cold stabilized. In the next couple of weeks I will be racking all of it, and after than filtering the wines to remove any tiny sediments the bentonite missed. After that we’re essentially ready to bottle… Already… time flies when you’re having fun!