One of the long, ongoing discussions in the world of home wine making is, “should I be bulk aging or bottling aging my wines?” While bottle aging wine has its merits, there are some good reasons to consider bulk aging. Here’s some food for thought when considering bulk aging vs bottling aging your wine.
What Is Bulk Aging Wine?
Bulk aging refers to storing the wine in something similar to a glass water bottle. Home wine makers refer to them as carboys. It’s important to have a container with a neck of some sort so that the head-space, or air gap, can be mitigated as the bottle becomes full. Aging wine is a bucket-style fermenter is not recommended. The carboy is usually sealed airtight with either a rubber stopper or cork stopper while the wine is aging.
Many home wine makers elect bulk age over bottling aging their newly made wines for months or even longer before moving the wine into bottles. The reasoning behind this could be anything from, “that’s how the wineries do it” to “I was waiting to get more empty wine bottles.”
Why Do Professional Wineries Bulk Age Their Wines?
In reality, the commercial wineries bulk age, or maturate, in bulk because it is a safer and more controllable than aging in wine bottles. It’s safer because air, light and heat can all be kept in check more evenly – these are the elements that can come together to produce oxidation in a wine. It’s more controlled because the maturation process is slowed down when oxygen contact is reduced. Wine in bottles have more air contact per gallon then wine in bulk.
Why Slower Is Better
It’s common knowledge in the wine industry that slower aging produces a better tasting wine, one that is more in balance. Oxygen is what drives the rate of some maturation processes, but not all of these processes respond equally to oxygen. As a result, a wine can become out of balance, as some aging process outpace others when aged too fast.
In addition, some aging activities in a wine are triggered in sequence – sort of a domino effect. One cannot happen until the other one occurs. These falling dominos are set off by the oxygen, but again, if too much oxygen is given, some of the maturation processes fall behind in the chain, again, putting the wine’s qualities out of whack.
For these reasons many wineries age in bulk before bottling. “How long?”, depends on the wine at hand and how the flavor and bouquet of the wine are developing. These elements are monitored to determine when it is time to bottle the wine. It could be weeks; it could be a year.
Bulk Aging Homemade Wines In Carboys
The home winemaker can use either glass or food-grade plastic carboys to do the aging. While you can use an actual cork stopper to seal up the carboy, I prefer using a rubber stopper. I also recommend using baling wire or similar to hold the stopper in place, otherwise changes in temperature or barometric pressure can cause the stopper to pop loose.
The wine should also be treated with a dose of potasssium metabisulfite before sealing it up to be aged. This is to eliminate any chance of spoilage and to help keep the wine’s color stable.
When bulk aging a wine in a carboy, be sure to monitor the flavor of the wine as time goes on, just don’t monitor it too much. About once ever 2 or 3 month you can take 1 or 2 ounces out to see how things are progressing. A wine thief will help you in this regard to get the wine from the carboys or any other glass jugs with a narrow neck.
After Bulk Aging The Wine
Once it’s time to bottle, you can bottle the wine directly from the carboys just like you normal would have without aging the wine.
Once the wine has been bottled there is a typical period of bottle shock that the wine will most likely experience. This is a temporary condition of the wine that results in a flat, lifeless character. Let the wine sit to condition for about a month and the wine should come back to its former self.
Whether or not you bulk age your wine in a carboy or individually in wine bottles, your wines will age none the less. So don’t feel that bulk aging vs bottle aging is a make-or-break decision. Just remember that air exposure to the wine is a premier factor.
Ed Kraus is a 3rd generation home brewer/winemaker and has been an owner of E. C. Kraus since 1999. He has been helping individuals make better wine and beer for over 25 years.