carboy aging

Winemaking Talk - Winemaking Forum

Help Support Winemaking Talk - Winemaking Forum:

bluedart

Member
Joined
Aug 3, 2017
Messages
51
Reaction score
13
My 1 gallon of Baco Noir wine has completely cleared and now I want to bulk age in the airlocked carboy for 9 months. I have added one campden tablet and will not be racking again. Will the campden tablet continue to protect the wine for the next 9 months.
 

Scooter68

Fruit "Wine" Maker
Joined
Aug 29, 2015
Messages
4,017
Reaction score
3,325
Location
Northwest Arkansas
Normal process is to rack every 3 months and dose with K-Meta at that time. You are pushing you luck if you don't dose with K-Meta or at least take the time and effort to determine the SO2 level in your wine.
Also even though your wine appears perfectly clear, you may be surprised at what precipitates out during that 3 month time.
 

bluedart

Member
Joined
Aug 3, 2017
Messages
51
Reaction score
13
So you are saying that the kmeta lasts about 3 months? But what about wine that is in a bottle for 1 or 2 years?
 

Scooter68

Fruit "Wine" Maker
Joined
Aug 29, 2015
Messages
4,017
Reaction score
3,325
Location
Northwest Arkansas
It can last longer but you can't be certain unless you test it.

In a bottle the wine is considered sealed from exposure to oxygen and the SO2 stays in the bottle.
 

tradowsk

Senior Member
Joined
Aug 20, 2018
Messages
242
Reaction score
90
When bottled, the cork allows a very, very small amount of gas exchange between inside and outside. But in a carboy with an airlock, gas can escape fairly easily out the airlock with enough pressure. Hence why you would need to dose with kmeta more frequently in bulk aging vs a bottle.

I don't think you need to rack if there's no or very little sediment. But you can top up the kmeta after 3-4 months in the carboy just to be safe.
 

MHSKIBUM

Member
Joined
Mar 5, 2020
Messages
79
Reaction score
96
Normal process is to rack every 3 months and dose with K-Meta at that time. You are pushing you luck if you don't dose with K-Meta or at least take the time and effort to determine the SO2 level in your wine.
Also even though your wine appears perfectly clear, you may be surprised at what precipitates out during that 3 month time.
Why do you need K-Meta for wine racked in bulk but not when it's bottled. If the air gap is kept close to the stopper, what's the difference?
 
Joined
Nov 5, 2006
Messages
4,915
Reaction score
12,484
Location
Raleigh, NC, USA
Why do you need K-Meta for wine racked in bulk but not when it's bottled. If the air gap is kept close to the stopper, what's the difference?
The short answer is that free SO2 binds with contaminants and neutralizes them. Once in the bottle nothing new can be introduced, while the carboy is not sealed in the same fashion.
 

bluedart

Member
Joined
Aug 3, 2017
Messages
51
Reaction score
13
When bottled, the cork allows a very, very small amount of gas exchange between inside and outside. But in a carboy with an airlock, gas can escape fairly easily out the airlock with enough pressure. Hence why you would need to dose with kmeta more frequently in bulk aging vs a bottle.

I don't think you need to rack if there's no or very little sediment. But you can top up the kmeta after 3-4 months in the carboy just to be safe.
How much KMeta would you need to add per gallon?
 

MHSKIBUM

Member
Joined
Mar 5, 2020
Messages
79
Reaction score
96
If I add K-Meta to bulk aged carboy, should I put in more K-meta before bottling 4 months later?
 

NorCal

Super Moderator
Super Moderator
Joined
Apr 17, 2014
Messages
3,677
Reaction score
4,922
Location
Sierra Foothills, Nor Cal
The big question is what is your pH. If your wine is 3.3 pH it requires 5X less SO2 than if it were 4.0 pH

I've never used Campden tablets, but saw this. Each Campden tablet equals 1/16 teaspoon of sodium metabisulfite and will impart approximately 75 parts-per-million of sulfur dioxide (SO2) to each gallon of wine.

If this is the case and your wine is in the 3.5 pH area, you are good for a while.
 

Raptor99

Fruit Wine Alchemist
Joined
Sep 6, 2020
Messages
410
Reaction score
611
Location
Oregon
There is a helpful chart at the bottom of this page: https://www.accuvin.com/wp-content/uploads/2015/04/How-SO2-and-pH-are-Linked.pdf It gives the target range of free SO2 based on the pH level. Here is more technical information: http://srjcstaff.santarosa.edu/~jhenderson/SO2.pdf

At pH 3.4 you only need 32 ppm free SO2, so half a Campden tablet, or 0.22 g Kmeta per gallon would be enough. But at pH 3.8 you would need twice as much.

Here is a formula for calculating how much Kmeta powder to add:
(ppm free SO2 needed) x (Liters of Wine)/0.57=(mg of potassium metabisulfite to add)
Source: Managing Sulfites in Wine
 

MHSKIBUM

Member
Joined
Mar 5, 2020
Messages
79
Reaction score
96
Normal process is to rack every 3 months and dose with K-Meta at that time. You are pushing you luck if you don't dose with K-Meta or at least take the time and effort to determine the SO2 level in your wine.
Also even though your wine appears perfectly clear, you may be surprised at what precipitates out during that 3 month time.
Does K-Meta need to be stirred in carboy? There's so little air gap, even a thin stir rod causes carboy to overflow.
 

Rembee

Country Wine Artisan 🍷
Joined
Jan 5, 2021
Messages
449
Reaction score
736
Location
Southern Mississippi
Rack off a gallon of the wine into a clean container. Add the amount of k meta that you need and stir. Then you can rack the gallon back into the main batch. I solve this problem by adding my potassium metabisulfite into an empty carboy before I rack the wine into it. This way the wine being racked stirs it up as it swirls in.
 
Joined
Nov 5, 2006
Messages
4,915
Reaction score
12,484
Location
Raleigh, NC, USA
There is a product that acts like Alka-Seltzer, a SO2 tablet that fizzes and dissolves. I was going to buy some last fall, but it was out of stock. I need to see if it's available.
 
Top