English ale fermenting for 3 weeks

[Jmio]

Hi guys!

Three weeks ago, we brewed our second batch, following this recipe:

BIAB Full Volume (No Sparge)
10 L batch (fermenter)
Grains
Maris Otter 6 EBC	2.000 g
Crystal Extra Dark 240 EBC	200 g
Hops
East Kent Goldings 6%	15 g - 60 min (boil)
Fuggle 4.2%	5g - 20 min (boil)
Misc.
Protafloc	0.11 tablet
Yeast
Safale S-04	7 g
Mash		Achieved
Initial Water Volume	13.97 L
Mash Temp	65°
Time	1 h
Pre-Boil Gravity	1.043	1.040
Boil
Time	1 h
Original Gravity	1.052	1.050
Fermenter
Water Volume	10.8 L
Final Gravity	1.011	1.009

It all went well, and the Pre-Boil Gravity and OG are close to the expected values from the calculator.

But, after 3 weeks, there is still activity in the fermenter.

I have been taking gravity readings with a refractometer, using Brewer's Friend Refractometer Calculator to correct the values, and for the last 8 days it has been stable at 1.009, but the fermenter is still expelling CO2 through the airlock every hour or so. The fermenter has not been opened at any time since brew day, the samples were taken from the tap. And the temperature has been stable between 16 and 19 °C.

Is it normal that it's taking so long to finish fermenting?

Thank you!

 

[The Baron]

I would say it is finished you can get what seems to be airlock fermentation or activity but it is the beer expelling co2. You have proved it has finished by doing 3 readings with the same values. Just keg or bottle as normal is my opinion

 

[DavidDetroit]

It's finished based on the readings.
Getting a bubble in the airlock every hour or so is not what I would call activity.
You said 16°C to 19°C. That could be enough for expanding and contracting especially if the volume of gas above the liquid is relatively substantial.

 

[obscure]

More likely it is just residual CO2 as the baron says, stable gravity readings aside S-04 I find tends to be extremely quick (when I use it I find it tends to finish in about three days and I tend to bottle on day seven).

 

[DavidDetroit]

it is the beer expelling co2.

Where would the CO2 be coming from if fermentation is finished and why wouldn't that reaction continue to lower the gravity?
Serious question as I've never heard that before.
Thank you.

 

[The Baron]

Hi DD I think you have answered part of the reason this happens already. The beer has locked in some co2 i.e it has some carbonation in it from the fermentation and the slight fluctuation in temperatures will aid this to be released usually slowly over days.
I think you are aware if you make wine that you have to degas it for the same reason and that quite a bit does come out when you use a degas wand on it.
Its like pressure fermenting that locks in a lot more of the Co2 so that you do not have to carbonate the beer by setting a regulator to the psi you require but there is already Co2 absorbed by the beer under normal fermentation to a smaller amount but it does vary in amounts with different brew/fermentations and thats why this anomaly can happen for longer on the odd time or two

 

[DavidDetroit]

I think you are aware if you make wine that you have to degas it for the same reason and that quite a bit does come out when you use a degas wand on it.

That makes sense. Appreciate it.

 

[Jmio]

Thank you, guys!

 

[Jmio]

Regarding carbonation, the app suggest to use 48.4g of sugar (regular table sugar) in 8 litres to reach 2.4 vol of CO2.

Would that be ok to get the carbonation level we usually have here in tap ales?

 

[Agentgonzo]

That sounds a little high for a British tap ale. This is the list of suggested carbonation for different styles that my app recommends

For a British tap ale, I would go for the lower end of the spectrum above (or even down a little lower towards 1 volume). For a bottled ale, 1.5-2 volumes what I aim for.

That being said, if you are going for 2.4 volumes, the amount of sugar feels right.

 

[Jmio]

Thank you! Got the feeling that it was too much. We'll go for 1.8 (29.6g) as it'll be bottled.

 

[Northern_Brewer]

Regarding carbonation, the app suggest to use 48.4g of sugar (regular table sugar) in 8 litres to reach 2.4 vol of CO2.

Would that be ok to get the carbonation level we usually have here in tap ales?

Definitely too high - 1.4 vol is often quoted for cask ale. Carbonation is a bit of a personal thing, and also it depends a bit on what size bottles you're using, as they have different ratios of headspace. Personally I find aiming the calculators for 1.7 vol for 500ml and 1.9 vol for 330ml works out about right. If you're bulk priming and bottling in a mix of sizes you can either split the difference for 1.8 vol, or bottle the 500ml first at 1.7 and then add a little bit more sugar before bottling the 330ml ones.

Going back to the first question - British yeasts are often finished in 3-4 days, you should be fine packaging after 10 days, and leaving it 3 weeks is generally way more than you need. As others have said, trust the gravity reading and don't pay too much attention to the airlock, it was probably just a bit of CO2 coming out of solution in response to temperature fluctuations (or the fermenter just getting knocked).

The only real exceptions to that with British yeasts are the low attenuation ones like Windsor and S-33 which can get a bit lazy at around 1.015-1.020 and then wake up again after a week or two, also the super-flocculators like WLP002/1968 can drop out before they're finished if they get a bit stressed through eg not enough oxygen. Usually some rousing will sort them. But those are extreme examples, generally British yeasts just get the job done, certainly if you're using the likes of S-04 and Nottingham.

In fact the problem is usually the other way, someone has a slight leak in their lid so they don't see any bubbles, then opens it up after 3 days and panics when they don't see any sign of activity, when in fact the yeast have already been and done. Gravity is the only test.

 

[Sandimas]

I brew mainly English ales, for bottling I use the minimum you can get away with, as you don't really want carbonated beer, just enough CO2 to keep is fresh. I don't calculate it but use just under half a teaspoon per 500ml bottle.

 

[Baldylocks Brewery]

Hi guys!

Three weeks ago, we brewed our second batch, following this recipe:

BIAB Full Volume (No Sparge)
10 L batch (fermenter)
Grains
Maris Otter 6 EBC	2.000 g
Crystal Extra Dark 240 EBC	200 g
Hops
East Kent Goldings 6%	15 g - 60 min (boil)
Fuggle 4.2%	5g - 20 min (boil)
Misc.
Protafloc	0.11 tablet
Yeast
Safale S-04	7 g
Mash		Achieved
Initial Water Volume	13.97 L
Mash Temp	65°
Time	1 h
Pre-Boil Gravity	1.043	1.040
Boil
Time	1 h
Original Gravity	1.052	1.050
Fermenter
Water Volume	10.8 L
Final Gravity	1.011	1.009

It all went well, and the Pre-Boil Gravity and OG are close to the expected values from the calculator.

But, after 3 weeks, there is still activity in the fermenter.

I have been taking gravity readings with a refractometer, using Brewer's Friend Refractometer Calculator to correct the values, and for the last 8 days it has been stable at 1.009, but the fermenter is still expelling CO2 through the airlock every hour or so. The fermenter has not been opened at any time since brew day, the samples were taken from the tap. And the temperature has been stable between 16 and 19 °C.

Is it normal that it's taking so long to finish fermenting?

Thank you!

I’ve just had the exact same on a very similar 23l batch. First time I’ve had visible activity beyond the first 7 days. But only been all grain for 15 mths so still early days.

 

[The Baron]

That's why it keeps being repeated on here that airlock activity is not to be trusted as a sign of fermentation, it can be a good indicator at times of how vigorous it can be but lies at both ends of the scale.
One how many of us have had fermentation with no or hardly any air lock activity and at the other end its still bubbling but fermentation has virtually ceased

 

[moto748]

Thank you! Got the feeling that it was too much. We'll go for 1.8 (29.6g) as it'll be bottled.

I think that's about right. If I understand right, your '1.8' is 1.8 g per bottle, yes? That's how I prefer to look at it. Assuming sixteen 500 ml bottles, I'd go 16 x 1.8 = 29 g of sugar.

I realise there are other variables, but I'm finding English bitters best in the range 1.8-2.0 g per bottle. and a little higher fr stuts, IPAs, etc.

 

[moto748]

Even a completely empty demi-john, fitted with a filled fermentation lock, can give some 'plinking', as the air in it expands and contracts with temperature!

 

[Sandimas]

I’ve just had the exact same on a very similar 23l batch. First time I’ve had visible activity beyond the first 7 days. But only been all grain for 15 mths so still early days.

It's all to do with the yeast you use, rather than being new to AG brewing. Some yeasts work fast, other work slow. I've had brews still fermenting after 28 days with some slow-burn yeasts, other finish much faster. The yeast the OP used S-04 is very reliable and is always finished by the 14 day mark, others (especially some of the MJ yeasts) can go on a lot longer.

 

[Northern_Brewer]

I think that's about right. If I understand right, your '1.8' is 1.8 g per bottle, yes?

I read it as 1.8 volumes of CO2.

 

[Jmio]

your '1.8' is 1.8 g per bottle, yes?

I read it as 1.8 volumes of CO2.

I was referring to 1.8 volumes of CO2.
I boil the sugar in about 250ml of water and mix it with the beer before bottling.