Low and slow fermenting - airlock or not?

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AnAppleADay

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Hi folks,

After producing a few seasons of insipid, "off" tasting cider, I've decided I may have been fermenting at temps that are too high. This time round, I'm trying to ferment within the 12-14 degree C range (54-57 F).

My question is - am I still alright to just put a tea towel or cheesecloth over the brew in primary, or should I be using an airlock due the CO2 protection being a bit less prevalent? I've always been a bit on the fence with whether to use an airlock in primary anyway, as it seems that there are pros to availability of oxygen during this phase, but still some risk of contamination. Thoughts?
 

Chalkyt

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Both Claude Jolicoeur and Andrew Lea (The New Cidermaker's Handbook, and Craft Cidermaking) seem to suggest that starting the primary in a somewhat open fermenter is worthwhile as long as there is a way of keeping nasties out (i.e. cover with a cloth, loose lid, empty airlock etc.) The idea being, as you suggest, that a bit of early exposure to O2 is helpful in this initial phase of yeast growth.

I do this in an open food grade bucket with the lid sitting on top but not clipped down, until the turbulent primary phase has settled (i.e the surface has "fizzed up" and then settled down). During this time a lot of CO2 is generated, and being heavier than air it sits in top of the must, keeping O2 away. This usually takes about a week in my cool store at 10C-15C by which time the SG is getting down to something below 1.040. By this stage not a lot of CO2 is being produced and the surface can be a bit exposed to O2, so it is the trigger for me to rack into a carboy with a proper air lock.

I find the advantage is that you can see what is happening, and you don't have a heap of muck trying to escape through the airlock.

Our apples here in Oz tend to be a bit low in acidity and I have found that adding crab apples or malic acid helps with any insipid flavour. I am presently mucking around with an abundance of Red Delicious apples which can make an uninspiring cider without some helpful addition.

Attached is a photo of a batch that I have ready to rack into a carboy (we are now into late Autumn/Fall). It has been fermenting for about a week and the turbulent surface is starting to settle down.

Anyhow, it works for me.

IMG_0241.JPG
 
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AnAppleADay

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Thanks @Chalkyt, appreciate your response. I'm down in NZ, so can definitely relate on the insipid apple front! Luckily we have a ready supply of crab/wild apples in these parts which I usually press alongside cultivated apples, and I have a small but gradually increasing supply of heritage cider varieties which will eventually improve the situation. I'm also experimenting with tannin addition this season, along with yeast nutrient to see if I get a better result.

My ferment is at about day 4 and it's moving along pretty slow on account of the cold temps in my garage, but the must is within the temp range for the yeast variety so I assume everything is fine. Probably going to be well over a week before I move to secondary however.

Anyway, sounds like we're on the same page, so thats good to know.
 

Kees

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An air lock's main function IMO is to keep oxygen out. Alcohol + oxygen = vinegar. A bit of oxygen may help to develop flavors but too much is no good. As long as large amounts of CO2 are produced there is an outward flow of gases (mainly CO2) through your cloth. When fermentation slows down oxygen will diffuse through the cloth and start to affect your brew.
I never add yeast nor use Campden and never have fungi causing trouble. They must be present in the juice so I think they do not develop due to low oxygen levels.
 

madscientist451

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Hi folks,

After producing a few seasons of insipid, "off" tasting cider, I've decided I may have been fermenting at temps that are too high.
I've always fermented low and slow, but some pro cider makers ferment faster. I don't use any temperature control when making cider, but I wait until later in the fall when the ambient temperatures drop off.
If you want your cider to be better, start with better apples. There's just no way around that. Apples are generally classified as early, mid-season and late season. I've found that late season apples produce better cider for me. Most commercial growers pick the apples before they are ripe. If you can find tree ripened fruit, that helps somewhat.
Changing your yeast selection may make a difference.
Adding yeast nutrient will speed up your fermentation, but it may be necessary with some yeast strains.
I don't see any advantage to not using an airlock.
 
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AnAppleADay

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Thanks folks. I'm a week into my first ferment of the season and it was going reasonably well until a round of unseasonably warm weather hit yesterday - my must temperature has gone up significantly even though it's in the coldest part of the house! Oh well, what can you do. Will be moving to secondary and fitting an airlock tonight in any case.

Agreed on the better applies @madscientist451 , I'm hoping that as my heritage cider trees mature my cider quality will also improve! The varieties of apples offered by the orchards here just don't cut the mustard when it comes to to making a decent brew.
 
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AnAppleADay

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An air lock's main function IMO is to keep oxygen out. Alcohol + oxygen = vinegar. A bit of oxygen may help to develop flavors but too much is no good. As long as large amounts of CO2 are produced there is an outward flow of gases (mainly CO2) through your cloth. When fermentation slows down oxygen will diffuse through the cloth and start to affect your brew.
I never add yeast nor use Campden and never have fungi causing trouble. They must be present in the juice so I think they do not develop due to low oxygen levels.
That's interesting, I had thought this approach was a bit too risky but I might give it a try in a small batch. I've only done one batch a long time ago without pitching yeast or adding k meta, and it actually turned out decent but I had thought the risk outweighed the rewards.
 
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