US-05 Yeast

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markp

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Last weekend (Sat 9th May) I brewed a pale ale - Propper Jobbie (see brewdays).

I used US-05 yeast for the first time.
I aerated well and pitched dry. Fermentation started quickly.....there were small bubbles visible after 3 hours or so and within 12 hours I had a nice 1.5 inch krausen on top of the wort.
We are now on day 8 of fermentation and I still have quite a lot of airlock activity - every 20 seconds or so. The 1.5 inch of krausen is also still there.

I normally use SO-4 or Nottingham, and am used to 3 days of vigourous fermentation which settles down quickly and then I rack in to a secondary on day 7 or 8.

Anyone else experience a slow ferment like this with US-05?
I found a few bits and pieces of reading on US-05, mainly to do with clarity issues after fermentation......but nothing about slow ferments.

I should take a gravity reading I suppose......but at half a pint per measure for my trial jar I am reluctant to take many. Time to learn how to use that refractometer I guess :lol:
 
This isn't so much a slow ferment more like US05 chewing up any possible sugar it can find . . .it is a bit of a demon as far as attenuation is concerned . . . and no the yeast head does not subside back into the brew. . . .Those that use US05 generally stop it in it's tracks by Crash Cooling down to under 5C once the gravity is where you want it.

So yes take a gravity reading and find out where your beer really is through the fermentation.
 
I use us-05 a lot and i find if you leave it two weeks in the fv the yeast will subside back into the brew, it might take a little longer than other yeasts but it's worth it :thumb:
 
Thank you Aleman and A T.

I had not heard or read about US-05 being a bit of an attenuation demon.
I will check the gravity tonight and see where we are.

ATB :D
 
Reading 6.5 brix, so SG 1025 - 1026 if my understanding is correct.

Some way to go yet then.......still getting airlock activity every 20-25 seconds.

ATB
 
are you using a refractometer to read the SG? Have you used a conversion table as they don't work so well with alcohol in the mix.

I only use them for OG then use my trial jar and hydromter best to taste the samples ;)
 
Ahhh yes prolix, thanks for that reminder......I had used the unfermented wort formula.

I'll be back after dinner :D
 
markp said:
Reading 6.5 brix, so SG 1025 - 1026 if my understanding is correct
Your understanding is not correct :nono: :nono: :nono: :nono:

You can only do a 4* Brix conversion for unfermented wort once the yeast start making alcohol you need a much more complex formula . . . most of us prefer to let brewing software do it for us. . . . There is an online calculator here
 
I'm sorry Mark, that was just the first online calculator I found. Using it, entering 1.058 in the first box middle line, and is 6.25 in the second box, it calculates the current gravity, as 1.004.

I agree with you though, in order to get an accurate terminal gravity, you really need to use hydrometer. For this purpose I bought myself a narrow range hydrometer from Hamstead homebrew.
 
Cheers again Aleman.

It does throw up more questions though (sorry :oops: ).
I can see now your earlier statment about attenuation is correct :rofl: .....how will this affect the taste of the finnished beer? I usually use SO-4 or Nottingham.
I imagine it is going to be extremely dry and very hoppy at 45 or so IBU.

Also, should I just let this run its course so to say, or stop it as you describe above?
My BeerSmith recipe says FG should be 1005.......so I'm not a million miles away (at this point anyway :lol: )

Thanks again :)
 
I think you are probably right It should be really dry and nicely bitter . . . Just the way I like them :).

I wouldn't want to let it go much past this point . . . but Is it likely to :hmm: Difficult to say depends on a lot of things really. . . For me after 8 Days I would automatically crash cool to start dropping the yeast out rather than any other purpose
 
I use s-05 a lot and, as stated above, it almost always loses its krausen after a couple weeks. Sometimes it's still fairly cloudy, though. Just the nature of the strain, I think. I've heard people say that the dry variety is an even higher attenuater than the liquid version of this strain (white labs 001). Can't confirm that from my experience as I've never bothered to use the 001. Why spend the extra money when s-05 is awesome.
 
I use US-O5 all the time, left for ten days the yeast head will sink - i`ve skimmed it before but had a cloudy brew, leave it to drop and your brew will be clear in two days from bottling! This is my yeast of choice i love pale hoppy brews and it delivers on hop profile every time - my proper job finished at 1002 and was 7% this yeast goes for it so use less grain and more hops :cool: My last brew is ready for bottling and is a darker ale using this yeast so will see how it turns out :thumb:
 
US 05 is my yeast of choice for certain brews, but it's a hell of a relationship :twisted:
I always have to crash cool to get the fg I want and the yeast head to drop, having said that I wouldn't leave a beer on the yeast cake for more than 10 days (own preference). Even after 2 weeks at 0-5 deg there is still more yeast in solution than every other yeast I've ever used :roll:
Having said that it's a great yeast for pales, IPA's and dry stouts, and I wouldn't be without it :cool:
 
Have used S-05 and it's predecessor US-56 for years. Attenuation wise, depending upon the fermentability of the wort it will achieve around the 75 - 80AA%.

Your wort OG of 56 now reading 07 = an Apparent Attenuation of 87% which is very high for this yeast strain, one could assume your wort was highly fermentable and also that fermentation has most likely ceased. Like all yeast strains, fermentation time using S-05 depends upon variables such as the amount of available sugar in the wort (OG), the fermentability of these sugars and both fermentation temperature and temperature stability. Best to monitor gravity as an indicator of terminal gravity.

S-05 is a good clean yeast for use in hop driven ales. Remember when balancing bitterness/sweetness in your beers to design in yeast attenuation. For beers with high IBU's design in a higher FG to balance the bitterness. This can be done by adjusting OG, mash temp, and/or percentages of dextrinous malts (crystals) in the grain bill or adjuncts in the kettle. Use the Bitterness/Sweetness Balance Formula when designing your beers rather than the BU:GU ratio, this takes the OG, FG and IBU's into consideration, however some experience is required as the brewer needs to be able to produce a wort with predictable fermentability before being able to apply the AA% for his yeast strain of choice. For instance a recipe of mine for an IPA using S-05 predictably achieves an AA% of 78% so I can adjust the FG up or down to vary the Balance Value. Or I can play with mash temp or crystal malt amounts to vary the fermentability/attenuation.

Conducted some experiments about 2007 and found oxygenation of wort to 15ppm prior to pitching actually extended lag time when using dried yeast. Best to just rehydrate and pitch. Todays S-05 does tend to stay afloat leaving a slimy yeast krausen on the beer. My normal fermentation regime is to allow 7 days more after reaching terminal gravity then drop the temp to 1-2 degrees for 3 days before kegging. Dropping temp to stop fermentation leaves some unfermented sugar in the beer which will continue fermenting should the temperature rise sufficiently during storage. A problem if bottle conditioning (bottle priming).

Cheers,

Screwy
 
Thanks for your responses guys, some interesting stuff there.

I decided to rack the brew in to a secondary last night and this allowed me to take a sample out for a hydrometer reading.
I was shocked and confused to find it reading 1014 :wha:

I have decided to leave the beer in the secondary for another 5-7 days and then take another gravity reading. Hopefully I can get a few more points out of it and then get it in the 'fridge.
The beer is still very cloudy, so there should be enough yeast in there to continue fermentation. Smells very good, tastes hoppy :lol:

I did mash a little higher than normal at 68 deg as I wanted to try and keep some body in the beer.

So, we'll see how we go over the next few days.
I'm a bit confused over the refractometer reading I got......first time of using but I am pretty certain I calibrated it right.

Thanks again for your input folks.
 
markp said:
Thanks for your responses guys, some interesting stuff there.

I decided to rack the brew in to a secondary last night and this allowed me to take a sample out for a hydrometer reading.
I was shocked and confused to find it reading 1014 :wha:

I have decided to leave the beer in the secondary for another 5-7 days and then take another gravity reading. Hopefully I can get a few more points out of it and then get it in the 'fridge.
The beer is still very cloudy, so there should be enough yeast in there to continue fermentation. Smells very good, tastes hoppy :lol:

I did mash a little higher than normal at 68 deg as I wanted to try and keep some body in the beer.

So, we'll see how we go over the next few days.
I'm a bit confused over the refractometer reading I got......first time of using but I am pretty certain I calibrated it right.

Thanks again for your input folks.


markp, haven't seen your recipe so not sure of the % of dextrinous malts (crystal etc) but seeing as your mash temp was 68 deg, then we can assume a lower AA% than average. So 1.056 - 1.014 / 1.056 = .75 so your fermentation using S-05 has achieved an Apparent Attenuation of 75% about spot on for conditions. Hope you can get a little more over time, but I'd say its finished, now give it some time to clean up after itself and you should have a tasty drop :thumb:

Screwy
 
I've had some US-05 fermenting a batch of a scottish 80/- recipe for three weeks now. I've checked it periodically and it's been going along at more or less 16 degrees for the entire fermentation. I started out at 1064 (higher than I was expecting after I'd over boiled) but the yeast has chowed through this well - even at the lower temperatures

At 7 days it'd fallen to 1026
at 14 days it'd gone to 1012
This morning it's at 1009 and some very slight signs of fermentation still.

The original recipe called for one month at 15/16 degrees so I'll rack it into secondary this weekend and move it to a cool dark place for it's last week before bottling. It's starting to warm up at last so I don't want it going over the top and being too dry. Already tasting quite clean, some good mouthfeel, alcohol and bitterness more apparent than I was expecting but it'll need time in the bottle to calm that down and get some fizz to finish it.
 
Screwy, thank you for your last post.....that makes a lot of sense now.
I am still a relative newcommer to AG brewing and had not even considered the attenuation aspect in the way that you have put it.

I had it in my mind that no matter what the OG, the yeast would ferment out to somewhere between 1004-1008, maybe with a higher mash temp 1010.
Looking at Alemans Effin Imperial Stout and the OG and FG he attains with that brew made the 'penny drop'. :lol:

Following on slightly from this.....by looking at how different yeasts attenuate and the OG of the wort, I guess you can work out pretty much where your FG will be and therefore when to rack off etc etc.

Thanks for your input too bellebouche.
 
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