My fermentation started rather late and is going on rather slowly

[meaulnes2]

Hi,
Three days ago, I pitched an IPA (20 liters at 1.058 SG) with a pack of US-05. Nothing happened during 27 hours, then the fermentation started (rather late based on what I am used to). Since the fermentation goes on at a steady slow speed (about 2 SG points / day according to my Float device). A few minutes ago I swirled the fermenter to prevent the yeast from laying at the bottom. I need to wait some time to see the result and if fermentation speed increases a bit.
Could the way I pitched explain what is happening ? In fact, I removed the yeast pack from the fridge 3 hours before pitching. The ambient temperature was about 25 °C (77 °F). I re hydrated the yeast in sterile water while aerating my wort (30 min. with an aquarium air pump). At the time of pitching the wort was at about 13 °C (55 °F).
I think the initial delay of 27 hours could be explained by the stress inflicted to the yeast (passing from 77 °F to 55 °F) but I cannot find an explanation to the slow speed afterwards. At the moment the wort temperature is about 19.5 °C (67 °F).
What should I best do now ?

 

[Erik the Anglophile]

I have started pitching 2 packs of dry yeast for my 20L batches and then giving the bucket a good shake before fixing the airlock, despite they say you don't need to areate with dry, I have found it gives me a quicker start and a more vigorous ferment...
After 3 hours the yeast should be close to room temp, I don't think that's the issue.
Could be old yeast, wort composition or anything really, since it has gone off now I'd RDWHAHB and try 2 packs next time.

 

[meaulnes2]

Thank you. The pack should be good until 07 2023. I don't think it is old. I am used to use one pack generally and have no problem. Do you really think underpitching could lead to such a delay and slow speed? Since I have swirled the fermenter the activity (bubbling) seems to be faster (36 bubbles per minute instead of 18 previously). The temperature increased a little bit. I will wait and see.

 

[Erik the Anglophile]

I can only speak from personal experience, but I have since starting to pitch 2packs for 20L (in FV) in the 40-50 range seen a significantly shorter lag time and more vigorous ferments, along with a much "clearer" tasting beer even straight from the fermenter.
For my smaller 15L batches of normal OG i pitch 1 pack.

Remember that commercial breweries are pitching closer to the equivalent of 1 dry pack/1 fresh whitelabs/wyyeast pack per gallon, so what many of us would consider "too much" are probably closer to just about right for giving the wort/yeast optimal fermentation conditions. The one dry per 5 gallons dogma is probably enough to get a decent ferment, but far from optimal and I personally will not risk it anymore in terms of possible unwanted flavours etc coming from a sub par ferment.

 

[Miraculix]

I can only speak from personal experience, but I have since starting to pitch 2packs for 20L (in FV) in the 40-50 range seen a significantly shorter lag time and more vigorous ferments, along with a much "clearer" tasting beer even straight from the fermenter.
For my smaller 15L batches of normal OG i pitch 1 pack.

Remember that commercial breweries are pitching closer to the equivalent of 1 dry pack/1 fresh whitelabs/wyyeast pack per gallon, so what many of us would consider "too much" are probably closer to just about right for giving the wort/yeast optimal fermentation conditions. The one dry per 5 gallons dogma is probably enough to get a decent ferment, but far from optimal and I personally will not risk it anymore in terms of possible unwanted flavours etc coming from a sub par ferment.

I 2nd that. The more yeast I pitch, the better the beer. I have not personally witnessed too much yeast. I also go with 2 packs dry for a standard batch size.

 

[meaulnes2]

Hi guys! I followed your advice and re pitched one pack.

 

[BrewnWKopperKat]

I followed your advice and re pitched one pack.

Noted.

The one dry per 5 gallons dogma

Let's set aside "derogatory labeling" for a moment to allow for a "future readers" observation. (Thank you).

At the time of pitching the wort was at about 13 °C (55 °F).

I've pitched and fermented US-05 a number of times at 55F. It's a slow starter. Never needed to pitch additional yeast to finish fermentation. And, personally, I don't get those undesired flavors that occasionally reported when fermenting this strain at those temperatures.

More generally, US-05 can be slow to start and slow to finish when compared to other strains. p 28 of the current Fermentis Tips & Tricks has a couple of charts that point this out. The text associated with the chart also indicates that individual results can vary.

---

With regard to pitch rates. Like so many other things with dry yeast I find the guidelines from the dry yeast providers to be a good starting point.

It's a starting point.

Feel feel to experiment. And report back.

Just save the derogatory language for somewhere else.

 

[BrewnWKopperKat]

 

[BrewnWKopperKat]

 

[BrewnWKopperKat]

Note that the above charts are at 68F.

Over the years, I've pitched US-05 as low as 55F and as high as 68F. Very different 'start-up' profiles.

YMMV.

 

[hotbeer]

For 20 liters, I'd probably have pitched more.

Could the way I pitched explain what is happening ?

Maybe. I've only pitched US-05 one way. Directly into 68°F wort with no aeration. As is one of SafAles's recommendations. And all six or so of the batches I've done this year were pretty much normal. Though visually they gave different impressions.

Hydrating is perfectly okay. But since you performed the process, that is something you have to look at to ensure you did everything correctly. So more added complication to both brew day and for figuring this out.

What should I best do now ?

Be patient. It'll be beer. Just might take a little longer. You could add some more yeast, but I wouldn't since it's been 3 days or more.

I'd keep the FV at 69°F. Especially if in a hurry.

Also, the temps on the sachet for US-05 aren't the current recommended temp range. The website and current literature say...

Ideally at 18-26°C (64.4-78.8°F)

But it'll still ferment at lower temps. Just slower.

 

[meaulnes2]

Note that the above charts are at 68F.

Over the years, I've pitched US-05 as low as 55F and as high as 68F. Very different 'start-up' profiles.

YMMV.

Thank you for you very relevant information. I can see on the curves above that the US-05 has an adaptation time rather long 24 hours (at 68F) and that the attenuation speed is rather low. This leads me to believe that at 55°F it is even longer.
On the pack it is said that you can pitch from 20 to 30 liters not speaking of the gravity. I think it is for a 1.040 gravity but I am not sure. One can think that 20 liters at 1.060 is the limit, and I am in.

On the curve above, the point where I pitched the new pack (what I probably had no need to do) is 1st June at 12:30. Temperature is stable now at 68°F.
Thank you again for your explanations, they will be very useful to me next time.

Thank you also to hotbeer for complementary information.

 

[meaulnes2]

Just save the derogatory language for somewhere else.

BTW have I used derogatory language? if so, I apologize because I didn't intend to do so. English is not my native language and sometimes I can use an inappropriate expression.

 

[BrewnWKopperKat]

BTW have I used derogatory language? if so, I apologize because I didn't intend to do so. English is not my native language and sometimes I can use an inappropriate expression.

It was not you.

---

eta: it should be possible to talk about different pitch rates without needing to label one pitch rate as "dogma".

 

[Erik the Anglophile]

Well the one pack is good for 5gallons/~20L saying is, as many other common knowledge things in this hobby, pretty dogmatic.
Then if acknowledging that is derogatory I do not know, IMO it is not.
Just think about HSA, that it could have any affect in homebrewers products was until not too long ago regarded as bullS, a truthful concept so obvious it did not even need an explanation, ie a dogma.
No intent to insult anyone, but in order to have a clear, meaningful discussion everything should be transparent and people able to call things what they are.

 

[BrewnWKopperKat]

Lallemand pitch rate calculator.

No dogma. Just a recommendation.

 

[Erik the Anglophile]

The dogma has come from the homebrewing community itself, not yeast manufacturers.
It does not matter, nevermind, I think we are talking past eachother atm.

 

[BrewnWKopperKat]

dogma is loosely "a point of view put forth as authoritative without adequate grounds."

There was a time when, with dry yeast, the pitch rate for each strain was pretty much the same and it was a one package for 5 gal of 'standard' strength beer. This pitch rate was based on info from yeast labs / brands.

Over the last couple of years, there are a couple of strains with very different pitch rates. Yeast labs / brands provided the appropriate guidance.

Over the last couple of years, there have been a number of posters (myself included) who noticed and commented on the difference pitch rate.

People will continue to unintentionally pitch at the wrong rate and come for forums for help. A quick pointer to yeast lab / brand product information is all it takes to brew better beer next time.

 

[meaulnes2]

It seems that my fermentation is close to the end. As a feedback hereafter is the fermentation curve from my Float device. Please be aware that the device is not that accurate. Generally initial gravity is rather exact but final gravity is somewhat bigger than actual. 1.023 is in reality about 1.011 .

As you can see it is close to the reference submitted by BrewnWKopper Kat.
I will let the dry hopping finish and then cold crash.