Is The Carboy Half Empty Or Half Ruined?

Wine Making JugsHi E.C.Kraus!
I’m new to home winemaking. I made red and white wines this year and have them resting in 54 L carboys (with air-locks) after the initial fermentation is completed. The storage room does have a pretty high temperature (65degF), but it doesn’t fluctuate.
After a month, I decided to start drinking the red one. It tastes great now. So, every weekend I open the carboy and have 1.5 L of wine siphoned into a regular bottle.
I’m wondering if opening the carboy every week (as a result more air in the carboy) can quickly harm/destroy the rest of the wine or not? Unfortunately, I couldn’t find the proper answer anywhere. I hope you, as a Guru in home wine making, could possibly advise me on this matter.
Thanks in advance for your appropriate reply.
Dear Michael,
Sorry to say, but what you are doing is just not going to work.
Your concerns are well placed. Having more air, or an increasing head-space, in any type of carboy will eventually be a bad thing for wine. In the short term–a few days or so–you’re probably okay, but over time the air will have its way with the wine.
The first thing that happens when you drain the wine from the carboy is it increases the surface contact area between the air and the wine. When the carboy is full and the wine is up into the neck, you may only have 3 square inches of contact space. When the carboy isn’t full you could have over a square foot of contact area–144 square inches or more.
What this all means for the wine is oxygen now has the ability to saturate into the wine at a much faster rate than before. Eventually the wine will begin to show signs of oxidation. The wine’s color will start turning brown, and the flavor and aroma will start to take on carmel characteristics.
The second thing having a half-full carboy can do to the wine is spoil it. Mold, bacteria and other little nasties are floating around in the air. They are everywhere. An individual cell or spore is no threat, but if it is in some of the air that is brought into the head space, it will have a place to land with plenty of nutrients available with which to grow.
Understand, that oxidation and spoilage will not happen overnight. But day by day, week by week it will slowly progress.
Having said all of this, the solution is simple. Be sure you are using sulfites on the wine such as sodium metabisulfite, and either bottle your wine or keep your carboys full. Even bottling the wine in gallon glass carboys or gallon glass jugs would be a vast improvement over your current situation.
Happy Wine Making,
Customer Service
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.

0 thoughts on “Is The Carboy Half Empty Or Half Ruined?

  1. As a follow up, is it any advantage if he used metabisulfite each week after siphoning?

  2. Michael, keeping a good supply of sulfites in the wine would help to minimize the effects of spoilage/oxidation, but this can only be taken so far before the amount of sulfites that permanently bond to the wine become excessive and negatively effect how the wine tastes.

  3. Can I use the plastic bottles (clear plastic or the PVC type) that bottled water, which I buy to make the wine from concentrate, be used for bottling the wine itself?

  4. Anthony, you can use the plastic water jugs for making wine just fine. However, it is important that you do not use any brushes or abrasives on the inside when cleaning. Keep the inside walls nice and smooth so that they can be sanitized more thoroughly.

  5. I fine keeping my wine in full gallon jugs and in the refrigerator does just fine for a bottle or two. Since I only have my garage I find keeping the remaining supply in the house in front of an air conditioning vent works fine.

  6. I make dry red wine from winexpert kits, I would like a much dryer finish taste. Can you recommend something I can add to my wine & at what point in the wine making process. Thank you, Tim

  7. Tim, the simplest thing to do is to make sure you are using a wine yeast that ferments to full dryness. I would suggest trying Red Star Brand: Premier Cuvee.

  8. Hello Lucci, these particular jugs are called demijohns. They are normally made to hold 15 gallons. We do not carry them simply because they are very expensive and very fragile, much more fragile than a 5 or 6 gallon glass carboy. Just do a search for demijohn on Google and you should find them, but be prepared to pay a small fortune, particularly once you figure in shipping.

  9. For how long I can keep the wine in the Carboy? Is the small residue of leek in the bottom will spoil the wine?

  10. Andy, I assume you are referring to the sediment in the bottom of the carboy. As long as there is no air-space in the carboy with the wine, it will keep just as good as a bottle of wine. But the wine needs to be up into the neck of the bottle. Also, any sediment that accumulates needs to be removed every few weeks. You should also be treating the wine with a sulfite such as Campden Tablets to help keep the wine fresh from spoiling, however you want to be sure that the fermentation has completed before adding this.

  11. My wine has been in the anaeroebic state 5 weeks. I have removed the sediment and there seems to be no more gas activity. Can I transfer to gal jugs, cap and let the aging process continue? Should I add sufite before I transfer?

  12. Mike, it would be fine to move the wine to gallon glass jugs for aging as you have suggested, but it is important that you confirm with a hydrometer that the fermentation has, in fact, completed and not has just become stuck before finishing. To answer your last question, you want to add the sulfites right before bottling.

  13. Would not topping the wine in the carboy with Nitrogen stop the oxidation and spoilage?

  14. I haven’t made wine for 20 years, and want to do it better this time!… I’m buying good wine now in boxes – the wine is actually protected inside a plastic bag. Is this technology available yet to the home wine maker?

  15. I have made wine from several kits. The juice comes in plastic bag with a nice stopper. It seems that these (Properly cleaned) would make a good way to store the final product. As you use/bottle the wine you can just press on the bag to get the air out and then reseal it. Leave the bag in the original box or pail for structural integrity.

  16. Hi, I just transferred my 2.5 gals of elderberry primary ferment from the bucket to the 5-gal carboy. It smelled VERY yeasty. I had followed a recipe for 5 gallons of wine (including pounds of elderberries, sugar, etc.) so filled the rest up with filtered water. It’s up to the neck, with a new airlock. I don’t see ANY movement of the airlock. My primary ferment sat in the kitchen (with cloths on top) for a week after the temperature dropped. Am I in trouble? Should I add a crushed Campden tablet? More sugar to see if the yeasts are still alive? Just sit around and wait to see what happens? This is the first elderberry wine I’ve made. I’ve also included an ounce or two of oak chips.

  17. Lisa, if you start out with 5 gallons of ingredients in a 2.5 gallon batch, I seriously doubt that your wine has fermented at all at this point. The sugar concentration would be too high for the yeast to ferment. I would add try to find an open 5 or 6 gallon fermenter to put the wine must back in. And pretend that you are just starting the wine. Add Campden tablets; wait 24 hours with the fermenter uncovered; add more wine yeast; and take it from there.