Secondary fermentation

Hi all,

Last March I collected enough birch sap for a demijohn of wine.

After primary fermentation, I transferred it to a demijohn, it clarified and I racked it off to a second demijohn (after about a month).

It's been two months now in second demijohn, there isn't too much sediment, so I'm not keen on racking it again. However it's still releasing gasses through the air lock.

While I know that its a case of "how long is a piece of string", I'm wondering how much longer (in a general way) it will be before the wine ferments out? The room it's in is usually around 18c.

Thanks,
Druss

http://paddy-halligan.blogspot.com
http://twitter.com/#!/druss_rua

BeerNut

Gas coming out of an airlock doesn't necessarily mean fermentation is happening. Checking for gravity changes is the only real way to know.

sharingan

I got my hands on a wine pipette so that I could take gravity readings from Demijohns. Ensure it is completely sterile before taking samples.

What original gravity did you have, and what yeast did you pitch with? Some of my local brewers get quite obsessive about pitching, and ensuring that there is enough healthy yeast to do the job.

I have heard that Birch sap has a long fermentation (3 months or so).

My experience of strong honey wines/complex sugars is that they ferment for a long time too (over 4 weeks with decent room temperature).

BeerNut

Thanks for the replies folks.

BeerNut wrote: »

Gas coming out of an airlock doesn't necessarily mean fermentation is happening. Checking for gravity changes is the only real way to know.

Just out of curiosity, what else would cause the bubbling coming out of an airlock?

Druss.

http://paddy-halligan.blogspot.com
http://twitter.com/#!/druss_rua

BeerNut

CO2 coming out of solution. The solubility of carbon dioxide varies with temperature, so as the temperature changes the liquid will sort of breathe.

TomCo

BeerNut wrote: »

CO2 coming out of solution. The solubility of carbon dioxide varies with temperature, so as the temperature changes the liquid will sort of breathe.

This is also why you don't want to open a warm bottle of beer

sharingan

Deleted User wrote: »

Thanks for the replies folks.



Just out of curiosity, what else would cause the bubbling coming out of an airlock?

Temperature can also cause boring old thermal expansion and contraction of the gas.

If there is significant gas in the DJ or carboy, this can cause gas to get sucked in through the airlock.

evolving_doors

Birch Sap?

sharingan

Armelodie wrote: »

Birch Sap?

There's an old river cottage episode which shows it being made (the one where he lives on a barge).