Fermenting!

So we now have grapes! Well, grape slurry; the official term is 'must', basically it's juice, skins, seeds, and a few stems.

With this batch, we put the must directly into our garbage pail - er, "primary fermenter", in addition to a few extra food-grade paint buckets that we will eventually dump into the primary fermenter - for ease-of-transport reasons.

After picking & crushing the grapes, there's actually not a lot to do. First, we put all in one food-grade Brute garbage pail (ours is 20 gal, so holds around 17 gallons of must).

Then we are sure to kill anything that will get in the way of fermentation by adding sulfites.

Yes - these are what have been considered bad, evil, unhappy elements to add to wine. Basically, sulfites exist naturally in grapes; a bit supplemental helps make sure the right yeast converts juice to alcohol, prevents nasties from growing in your juice/wine, and a variety of other things. I'm as much an all-natural gal as next (probably moreso), but a bit of sulfite to prevent disaster over so much juice/wine seems worth it until I get more experienced and experiment with letting the *natural* yeasts of the grape skins ferment the wine.

In any case, after getting the juice in nice clean Brute, and adding sulfite (25 ppm, which for our 18 gallons meant about 1/2 tsp), we wait for a day and then add yeast - the culture that converts sugar to alcohol.

Last year, we used a yeast called Premiere Cuvee, made by Red Star (they make lots of yeasts, and one of the more common bread yeasts even). Premiere Cuvee is basically indestructible - converts sugar to alcohol quickly, violently, and good for grapes with the relatively high sugar content we have.

For our earlier batches, we used Premiere Cuvee. As always, it worked like a charm.

This, our third batch (second of 2007 season), we decided to try something new: we have pretty high acid in our grapes, so we like doing something called malo-lactic fermentation (MLF in winemaker terms). This is a process that converts malic acid (harsh, acidic-tasting) to lactic acid (cream, butter, yum!). Overall acidity decreases a little, but the acid taste decreases a LOT. And it makes your wine smoother. The extreme / easy to identify taste is that buttery taste in those thick CA Chardonnays, recently underrated in my opinion but that's another topic I'd rather not take on right now.

In any case, MLF cultures are sensitive to
(a) alcohol (they don't like >15% alcohol wines we tend to get with our grapes)
(b) sulfites (they don't like >50 ppm sulfites, either active or total, which is the rate most winemakers add even before fermentation)
(c) acid - strangely enough, while they lower the acid of wine, too high an acid count makes them not work. Again, here in CA our grapes are pretty acidic, so we tend to be on the high end of this scale too.

SO, because of this, our friends at Fermentation Settlement recommended that we try running MLF at the same time as we ferment. Crazy I thought!

But, I read up on the topic, considered (a) through (c) above, discussed with my husband / partner in crime, and decided why not, let's give it a shot.

To do this, we needed to re-think our indestructible yeast strategy - finding something that would take a bit longer to convert sugar to alcohol, such that the bacteria would have more time to convert that malic acid to lactic acid before the alcohol climbed to too high territory. So, we decided the yeast in the image here - and with it, added "Fermaid" and "DAP" (both elements that help the yeast along). And added

After all of that, we let that sugar convert to alcohol! To do so, after adding the yeast the gunk in the Brute gets warm, and starts bubbling. And it sends all those skins & seeds to the surface. But to leave them there is no good, they need to be surrounded by the liquid to fully convert, and not develop their own funk.

So, twice a day I sterilize my hand, and arm up to the elbow, and push those skins back down into the juice that's bubbling away. Like everything else in winemaking there's a technical term for this - it's called punching down the "cap". I call it getting your arm saturated in wine, often I go to bed with that sweet yeastey grapey smell that's hard to get out of your skin. Not a bad thing by any stretch of the imagination.

You do this for awhile, in fact if you're gone for a weekend you need to convince your neighbor it's a good idea to do this twice a day. Luckily our neighbor likes wine, and appreciates the hokey-ness of our operation. Yeay!

And you keep doing this - in our case until the cap "falls". More on that when it happens . . . probably in a couple of weeks.

APPENDIX: Winemaking stats
Leach 2007 Cab Sauvignon Harvested Septmeber 29, 2007
Measurements:
- Must: 24.7 Brix- TA 6.0 via titration method; 8.5 via Accuvin; 8.0 per Don Leach (grower)
- pH 3.8 via our crappy test strips; 3.3 per Don
- Added 0.5 tsp Potassium Metabisulfate, 25 ppm (half dosage, since we plan to run MLF during fermentation
- Added yeast AND Viniflora Oenos on September 30