The vineyards have been stripped of their fruit, the juice is in the winery, and I am no longer getting attacked by berries and fruit flies; the harvest part of harvest is over. So what am I still doing here?
I'm waiting on wine.
The work of winemaking continues past harvest and crush. Most of the wine has now gone through alcoholic fermentation (though some stragglers remain, particularly the native fermentation Chardonnays, which seem determined not to give me the satisfaction of seeing them finish), but our focus has moved to malic acid.
The secondary fermentation that all of our red and many of our white wines go through is malolactic fermentation, the process by which tart, apple-like malic acid is converted to milky lactic acid. This change softens the wine and happens thanks to lactic acid bacteria that munch up the malic acid to produce carbon dioxide and lactic acid. The process can take place naturally in the wine, and for our natively fermented lots we let the lactic acid bacteria already present do its thing. For wines that were inoculated for the primary alcoholic fermentation, we add the lactic bacteria Oenococcus oeni, which smells like powdered ranch dressing mix and malt balls.
These inoculations are simpler (and less messy) than those with yeast, and have become a fairly routine part of my work. The problem is that—same as with the yeast—once inoculated, the wines have to be checked. We do malic checks once a week, at which time I get to return to the barrel rooms and sample from as many barrels as I can reach (I have sworn off the dreaded stepstools and now I climb the barrels like an alcohol jungle gym). Our lab robot (an actual robot—I'm not making a reference to the routine nature of being a lab tech) tests the samples, and once a wine has completed malolactic, it will be mostly left alone until blending.
So we are waiting and checking and waiting and checking. As wines reach completion, we are increasingly busy in the lab—each finished wine needs a full analysis to make sure that everything looks good. The best part of this final round of lab work is getting to taste the baby wine. We have a centrifuge to spin down samples and remove solids from the wine so as to avoid clogging up any of our fancy lab machinery. This is a rather crude way to filter, but the resulting wine is, well, wine. We've made wine. It smells like wine. It tastes like wine. We can measure its sugar and alcohol to confirm that it is wine.
These wines are young, not ready to drink, and the earliest releases won't be until next year. But the juice that we crushed, pressed, inoculated (or not), checked compulsively, cleaned up after and waited on, is becoming wine. Fermentation works like magic. Or science.
About the Author: Sarah Chappell is a winemonger and writer living in
Brooklyn Napa. She holds the Advanced Certificate with Distinction from the Wine and Spirit Education Trust and has contributed to Foodista, Palate Press and WineChap. Follow her on Twitter @chapsholic.