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Limiting Air in Fermentation

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Closed transfer into a bucket. Transfer hose goes into the airlock hole. When finished transferring, pull out the hose and put an airlock in.
 
Have your carboy filled up into the neck, and use an airlock (super-cheap).
I am just worried about the loss of liquid between primary and secondary. I know that if I making similar cider in the future I can top up the carboy with cider I have already made. But what should I do for the first time or one off batches
 
I've brewed a lot of beer, but have not yet done cider, though I intend to so I'll be watching this thread;
Is there any good reason to use a secondary with cider? In primary, fermentation will purge the vessel of air, but moving to secondary is just adding it to air unless you've purged the vessel. Why not just leave in primary?
 
I do my primary fermentation (i.e. say 1.050 to 1.030) in an open container for two reasons. Firstly, I can see what is happening without needing to measure SG etc, and know that when the turbulent fermentation settles it is time to rack to a secondary carboy. This turbulent fermentation can create a bit of a mess if it squeezes out of the top of a primary carboy or airlock (the foam can leave the airlock dry if you don't keep an eye on it). Secondly, there is initial exposure to O2 (good for yeasts to get started) then the cider is protected from air when a CO2 layer builds up.

My primary ferment is always a bit more volume than the secondary fermenter holds, so the secondary ferment racking fills the carboy and leaves a lot of gunk behind in the primary container. This racking normally reduces the yeast activity and slows the fermentation rate which is useful if trying to pick the right SG to intervene if controlling sweetness or bottling for carbonation is planned. Also, any additions like fruit, tannins, hops etc don't involve stirring up vast quantities of lees. Any surplus cider at this stage is kept aside for top-up if it is needed.

Anyhow, that is what I do and why I do it. It suits my methods which mostly are directed at a slightly off-dry (5g/L sugar) lightly carbonated (2.0 to 2.5 vols of CO2) cider. I haven't really seen any difference between methods or any oxidation issues, but racking to secondary just provides a bit more control for me. I can leave the cider to mature without worrying about autolysing and unwanted flavours from the lees.

"You pays your money and makes your choices".
 
I do my primary fermentation (i.e. say 1.050 to 1.030) in an open container for two reasons. Firstly, I can see what is happening without needing to measure SG etc, and know that when the turbulent fermentation settles it is time to rack to a secondary carboy. This turbulent fermentation can create a bit of a mess if it squeezes out of the top of a primary carboy or airlock (the foam can leave the airlock dry if you don't keep an eye on it). Secondly, there is initial exposure to O2 (good for yeasts to get started) then the cider is protected from air when a CO2 layer builds up.

My primary ferment is always a bit more volume than the secondary fermenter holds, so the secondary ferment racking fills the carboy and leaves a lot of gunk behind in the primary container. This racking normally reduces the yeast activity and slows the fermentation rate which is useful if trying to pick the right SG to intervene if controlling sweetness or bottling for carbonation is planned. Also, any additions like fruit, tannins, hops etc don't involve stirring up vast quantities of lees. Any surplus cider at this stage is kept aside for top-up if it is needed.

Anyhow, that is what I do and why I do it. It suits my methods which mostly are directed at a slightly off-dry (5g/L sugar) lightly carbonated (2.0 to 2.5 vols of CO2) cider. I haven't really seen any difference between methods or any oxidation issues, but racking to secondary just provides a bit more control for me. I can leave the cider to mature without worrying about autolysing and unwanted flavours from the lees.

"You pays your money and makes your choices".
Your method sounds good, but just two things to mention that might otherwise cause a bit of confusion.

You are using a "real" secondary. Which means there is still a lot of fermentation going on in the second vessel. Most of the folks here are meaning basically just vessels for bulk aging when talking about secondaries.

This is why your open fermentation works. It is not because of a co2 layer, a co2 layer does not exist. It is a myth. But your yeast is so active that it continuously scavenges all the oxygen that is being introduced during primary. So all good, good practice.

This wouldn't work if you would rack much later, when fermentation is done.
 
Yep, Miraculix could be right about the CO2 layer. I checked Jolicoeur, Lea and a few other sources. They don't refer to it so I think that the idea may well have stuck in my brain from a post on a forum in the dim, dark, past, about leaving a primary fermenter open but covered to keep any nasties out.

What I think happens in my case, or at least it seems to with my approach, is that the thick foam that builds up during the primary fermentation comprises lots of gunk trapped in with C02 bubbles (I grind and press my own apples so there is plenty of scope for the must to contain solids). I guess this foam behaves like a physical blanket to protect the cider from the air, as it can end up 1 -2 cm thick. As suggested, the active yeast probably also scavenge any O2 that might cause a problem. As C02 production slows, the foam settles and the gunk falls to the bottom, hence the need to rack to a secondary carboy at that point.

Generally, my ferments take off quite robustly if I use S04, especially if I add about 1/4 tsp of DAP. When I have apples again (April or May) the plan is to start without DAP and only add it if fermentation stalls. I do find that with my late, old, and unfertilised apples, S04 sometimes stalls around 1.010 - 1.015 as it is a high nutrient demand ale yeast and such apples can be low in YAN. This is quite handy for managing fermentation for a carbonated cider with just a touch of sweetness. i.e. add just enough extra sugar after stalling to generate the C02 level and residual sweetness that I want.

Cheers!
 
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Yep, Miraculix could be right about the CO2 layer. I checked Jolicoeur, Lea and a few other sources. They don't refer to it so I think that the idea may well have stuck in my brain from a post on a forum in the dim, dark, past, about leaving a primary fermenter open but covered to keep any nasties out.

What I think happens in my case, or at least it seems to with my approach, is that the thick foam that builds up during the primary fermentation comprises lots of gunk trapped in with C02 bubbles (I grind and press my own apples so there is plenty of scope for the must to contain solids). I guess this foam behaves like a physical blanket to protect the cider from the air, as it can end up 1 -2 cm thick. As suggested, the active yeast probably also scavenge any O2 that might cause a problem. As C02 production slows, the foam settles and the gunk falls to the bottom, hence the need to rack to a secondary carboy at that point.

Generally, my ferments take off quite robustly if I use S04, especially if I add about 1/4 tsp of DAP. When I have apples again (April or May) the plan is to start without DAP and only add it if fermentation stalls. I do find that with my late, old, and unfertilised apples, S04 sometimes stalls around 1.010 - 1.015 as it is a high nutrient demand ale yeast and such apples can be low in YAN. This is quite handy for managing fermentation for a carbonated cider with just a touch of sweetness. i.e. add just enough extra sugar after stalling to generate the C02 level and residual sweetness that I want.

Cheers!
Be very very careful with late dap additions. Chances are there that the yeast does not utilise all of it. The rest that stays in solution will completely ruin your cider.
 
I've brewed a lot of beer, but have not yet done cider, though I intend to so I'll be watching this thread;
Is there any good reason to use a secondary with cider? In primary, fermentation will purge the vessel of air, but moving to secondary is just adding it to air unless you've purged the vessel. Why not just leave in primary?
There's no need to purge air with Co2. Cider doesn't oxidize by looking at it wrong like beer does. Rack it as many times as you need.
 

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