Ask Wine Wizard

Topping Up With Gas, Freezing Kit Juice: Wine Wizard



Argon gas
My carboys are 6 1⁄4 gallons (24 L). I am making mostly heavy reds and want to bulk age in glass carboys for up to twelve months before bottling. I don’t mind topping off with a small amount of similar wine every once in a while but what do you do when making an Amarone? I certainly don’t want to pour in several bottles of $65 Amarone! I have access to a cylinder of pure argon gas and want to backfill the headspace of the carboy. I would also be adding sulfite every 2–3 months to the carboy as well. How long does this technique last before you need to backfill again if you don’t open the airlock/stopper?
Michael D. Randow
Los Alamos, New Mexico

How long will a layer of argon or CO2 be effective in protecting the wine or must from oxygen?
Roger MacWilliamson
Hollister, California

Since these two questions are related I will answer them together. Layering ones’ containers with argon or CO2 gas may seem like an easy, pat solution to un-topped containers. It’s heavier than air so one would assume that a nice layer of it over the wine would be just like having a completely topped container. Alas, like so much in winemaking, it is not that easy. Even if you slowly and carefully dispense the argon into the top of your container, you are still only mixing it with the oxygen, nitrogen, etc. (viz, air) that is already there. Ergo, you will never achieve a 100% inert gas blanket.
Even with measuring and monitoring the dissolved oxygen content on top of the gas-layered wine, I have never found a gas layer to be able to out-perform a topped container. It may keep your wine sound for 1–4 months but beware of VA  (volatile acidity) creep, free SO2 disappearance, spoilage and oxidation thereafter. Reds fare better than whites and wines stored in cooler temperatures do better. Using argon is probably okay for a short term, as long as the containers are then topped up for long-term aging and the gas is replenished every couple of weeks. There is really no substitute for a topped vessel, however.
So the short, quick and not-so-fun-to-hear answer is that we simply must buy break down containers, smaller carboys or simply make enough wine to fit the containers we have. There are variable-capacity tanks out there, but those must be monitored constantly for seal integrity (they are not ideal either). Home winemakers can buy or trade their buddies for appropriate topping wine to add to their containers, but how much do we really want to spend? The commercial industry has battled this problem since time immemorial and no winemaker I know feels like he or she has enough “little tanks.” We buy as many as our budgets will allow and then use argon and CO2 (regretfully and carefully) to make up
the difference. 

Freezing kit juice
Will freezing affect the juice I get in a 5-gallon (19-L) kit? I am concerned about the variations that occur in home winemaking. My 6-gallon (23-L) primary fermenter works well but I only have one shot per kit. I want to take a standard kit (10-liter bag of Grand Cru Cabernet Sauvignon juice) and split it into five 2-liter batches. These batches would be stored, frozen in Ziplocks, awaiting their turn in my 1-gallon (3.8-L) primary fermenter. This would allow me to test the effects of acid adjustment, oaking, extra rackings and vacuum degassing using a common raw material starting point.
Jim Spencer
Greensboro, North Carolina

I think your idea of freezing small portions of kit juice is fantastic! I have always encouraged readers to experiment in meaningful ways that work for them and their particular circumstances; and it sounds like your arrangement will work for you.
The juice and concentrates that come with kits are already relatively microbially stable and are generally homogenous so they should freeze very well. I would just make sure that you measure your portions accurately and that you use your frozen material within three months or less. Also, Ziploc and other similar zippered plastic bags are poor vapor barriers, which is another good reason to use the frozen juice within three months of opening the kit container.
You might also want to be aware that when you thaw your frozen juice, you may observe some solid material that has “come out of solution” with the cold and has fallen to the bottom of your freezer containers as sediment. This is entirely normal and is exactly what happens when a wine is cold stabilized in the cellar. Cold can cause molecules in the wine that normally would be soluble at warmer temperatures to want to condense and become solids. If these tiny solidified molecules become big and heavy enough, they are no longer dissolvable in the wine and fall to the bottom of the container. They can look like small grains of sand or crystals and may be clear or slightly colored, if the wine has any pigment to it.
Actually, the fact that these solidified “wine crystals” can sometimes look like shards of glass is the reason that most commercial wineries cold stabilize all of their white (and some of their red) wines. Wineries are worried that un-educated consumers will believe that any crystals present are shards of glass and in a bid to avoid any panic, wineries pre-empt any possible sedimentation by subjecting wines to extreme cold (usually 30 to 40 °F/-1 to 4 °C) for a period of time (usually 24–72 hours) and then filtering the wine. “Wine crystals” and any other kind of sediment that could precipitate from juice with cold temperatures are completely harmless and won’t affect the quality of a fermentation to follow. For more information about stabilizing wines, see Daniel Pambianchi’s feature article in this issue, starting on page 46 and his “Techniques” column with tips for troubleshooting starting on page 71.
Finally, kit ingredients are highly buffered and tailored specifically to work a certain way, so tweaking the acidity can be tough. My colleague, and WineMaker’s “Wine Kits” columnist, Tim Vandergrift, recommends that acid adjustments be done post-fermentation on kits.

UC-Davis graduate and professional winemaker Alison Crowe has been answering hundreds of your winemaking questions as the “Wine Wizard” since 1998. Her Wizard columns have been collected in The Winemaker’s Answer Book which is available at  winemakermagstore.com. Do you have a question? Send your inquiries to her at: [email protected].  Unfortunately,  Alison cannot respond personally.