"Warm-Up" Wine Step 3: Degassing and Clarifying

Before we moved on to the next step, we enjoyed the afternoon at Oak Barrel's Pre-Harvest Festival, a chance for home winemakers to show off their creations, chat about the craft, or just drink a ton of wine. The good people at Oak Barrel put this event on for free, which is pretty impressive given the amount of wine and food being offered.

To start the degassing step, we first transferred the wine from the carboy to the fermenter, then back to the sanitized carboy. The "real" way to do this is to just use a new carboy, but Burdell Cellars doesn't quite have that production capability yet. We got a new toy since last time, the auto-siphoner, so that we don't have to use the fish tank method anymore.

Here it is going back into the (sanitized) carboy. The foam is residue from the cleaning process. This particular cleaner is especially nice because you don't have to rinse out the cleaner--and risk re-contaminating the vessel--after you clean it.

This is what the wine looks like once the transfer finished. Notice all the bubbles! That's what we're trying to get rid of in this step. (Sparkling wine is a little above our capability at this point.) The spoon is inserted wrong-way-in because that's what we're using to stir; stirring vigorously promotes degassing. The degassing process, according to the kit, was to take anywhere between 10 minutes and 3 days, stirring every 10 minutes. That's an awfully big range, and an awfully demanding stirring requirement, but we pronounced it degassed after 2 days of intermittent stirring.

Next up was a few additives. Once the wine was sufficiently degassed, we added the remaining ingredients in the concentrate kit. First up was a clarifier...

...which Forrest is dissolving in water and adding to our carboy.

The final two additions were kieselsol and chitosan, two stabilizers sometimes referred to as "fining agents". These help to remove remaining particulates and sediment in the wine.

Last up was one more vigorous stir, to make sure we'd gotten all of our additives thoroughly mixed.

And here it is now. The amount of bubbling decreased dramatically after the degas/clarification process, which you can see. It's harder to see the consistency of the wine, but it's a lot clearer, resembling the appearance of a wine you'd actually drink on purpose.

The wine will stay in the carboy for another few weeks, when it will be ready for bottling.

"Warm-Up" Wine Step 2: Racking

After six days of primary fermentation, the wine's specific gravity--a measure of its density relative to water--had decreased from about 1.1 to less than 1, indicating that a significant fraction of the concentrate's sugar had been fermented to ethanol. That meant it was time to rack the wine. "Rack" simply means to transfer the wine to a new vessel--in this case, a glass carboy--to aid in clarification and settling. Between all the yeast we'd dumped in last week, the oak float, and the natural sediment present in the concentrate, there's a lot of junk in the wine you don't want to drink.

The easiest way to rack a wine is by simple siphoning. We put the fermenter on a chair to add some more hydraulic head, started the siphon, and let it go for several minutes.

Kierston's wealth of experience with fish tank siphoning proved valuable here.

This is why you rack: you don't want to drink any of this.

Here's what it looks like once it's fully racked to the carboy. Notice how turbid it is, in contrast to attractive, translucent mature wine. A combination of settling, degassing, and clarification will improve its appearance.

Forrest hasn't been hitting the carboy--he's (understandably) proud of our efforts!

The next step from here is to wait for the specific gravity to decrease again, to about 0.97. At that point, we'll rack again and begin to degas.

"Warm-Up" Wine Step 1: Primary Fermentation

Our first step in setting up a garage winery from scratch was to buy equipment. Fortunately, the friendly guys at The Oak Barrel sell everything a novice winemaker might need. It's pretty cool that Berkeley has a winemaking shop, and it's an especially convenient walk from Burdell Cellars.

Here's some of our equipment. The big plastic bucket is the primary fermenter. That's where the concentrate (or, in the future, actual grapes) and the yeast go during the first step of winemaking.  The brushes are for cleaning the vessels. In this picture, we're sanitizing the primary fermenter and brushes with a percarbonate solution--apparently this is a disinfectant of choice in the food and drink industry because it disinfects then decomposes to water.

Kierston and Forrest are dumping the bag of concentrate into the fermenter. The concentrate is Cabernet Sauvignon juice with sugar plus sulfites already added. Again, for future batches, we'd be putting crushed grapes in here.

Once all the concentrate was in the bucket, we diluted to 23 liters (or roughly 6 gallons) total volume, which will eventually yield thirty bottles of wine. We added some wine yeast, which is nothing more than a selected strain of Saccharomyces cerevisiae.  In total, we added 5 grams of yeast, quite a lot, but probably necessary to ferment the 23 liters.

Here's a closeup!

Our wine kit also came with oak chips--this is a great way to give the wine an oak barrel-aged flavor without getting an actual oak barrel. It's not as authentic, of course, so we've contemplated acquiring an actual oak barrel in the future, which might not be so insane as it sounds. Here's Forrest preparing our "oak float," the name we gave to our boiled oak chip solution.

 This is what the proto-wine looks like with the oak chips stirred in.

Finally, we sealed the fermenter and attached the airlock. Within a day or two, the airlock started "burping," releasing carbon dioxide as a fermentation byproduct--that's how we knew we were making wine!

Next time: transferring to a carboy for the secondary fermentation.

Opening Burdell Cellars

Kierston, Forrest, and I are all chemical engineers. We toured France together about five years ago and all ended up moving to northern Calfornia for grad school, two of the winiest places in the world. So it was only a matter of time before we started up a winery of our own. Thus was born Burdell Cellars, a tip of the hat to the Georgia Tech legend of the same name. We're all new to the amateur winemaking scene, though we're all enthusiastic to get more into it and would appreciate any advice or experiences that the rest of the community could share.

Our plans for production year 2012 include

• a "warm-up" batch from Cabernet Sauvignon concentrate, in fermentation now, and expected to be ready by September (30 bottles)
• our first "real grape" effort--right now, leaning toward a Central Valley Syrah (30 bottles)
• various meads and fruit wines, in smaller batches (1 gallon or so)

We'll be posting all about the production of our wines, from purchasing the equipment through fermentation and finally to tasting, as well as other wine-related experiences (and even the occasional review!). We hope we can combine knowledge of science and engineering with a burgeoning passion for wine into something exciting and delicious!