S-04 yeast attenuation (2024)

First thing is, are you aerating the wort well?

Secondly, yeast is a major player in brewing beer, you can really improve your beers by finding strains that suit you and the beers you make, and learning how to get the best from them. I think for ales it's worth getting into liquid yeasts, yeasts from breweries, yeasts cultured from bottle conditioned beers. And yes, learn about different yeasts, their attenuation, effects of temperature etc.

I've not had issues when I've used S-04 - in fact, it usually goes off like a train and starts ferrmenting like mad.

I see what you mean about some companies putting the same yeast in all their kits regardless of style (see HBC Extract Kits reviews - they all came with S-05). But actaully S-04 should be a good match for a Theakstons OP clone as it's supposed to be a British Ale style yeast.

Don't have my Safelabs data sheet here so I don'y know off hand what the expected attenuation is supposed to be for S-04.

timcunnell said:

Hi Redron
I know what you mean about kits coming with S-04. I have been ordering my AG kits from HBC (their custom mash kit option was really handy recently for making up a clone recipe). Actually, on the clone kit the recipe I was following said to use Wyeast Nottingham, but this is not an option with the HBC custom kits, so I asked them in the notes to send whatever they thought would be a good replacement, and they sent S-04!
It has been working fine for me though to be honest. I did use it recently on the porter that I did - which I mistakenly brewed a little short. I got higher than planned SG (1054 I think), and I wasn't able to ferment lower than 1014 - but that would match the expected attenuation I guess.
Just wondering, what about your mash temp? Any chance that could be a little high? I had to replace my original mash thermometer as it was reading around 10c cold!

Click to expand...

I've just tested my cheapo 5 quid digital thermometer with the probe in a pan of boiling water and it reads 93 deg, as it usually does when boiling the wort. That is way out of what it should be ! So it is quite possible I have been mashing at 7 deg too high with resulting unfermentable sugars....
Measuring temps in a bag of mash I have found to be a bit hit and miss as it can vary so much throughout 32 litres of sugary, grainy mush.
Thinking on, a thermometer is a really important bit of kit to a brewer so I guess I need to invest in a decent one.
Any pointers.... ?

Yes mate I came to a similar conclusion when I started AG brews I quickly realised that I was not helping myself by using a cheap/unreliable thermometer.

I actually bought a couple of these temperature controllers from eBay (like this http://www.ebay.co.uk/itm/Digital-S...h-Sensor-ZY-/281808824463?hash=item419d1d688f) because I was experimenting with possibly modifying my Peco boiler so it would maintain mash temperature automatically. But actually I've found that it is fine just being left with a duvet wrapped round it. But these are handy for just dangling the probe into a liquid and getting a temp reading. Plus you can calibrate them against something reliable.

For a simple quick and reliable read though I guess I'd go for something like this http://www.brewuk.co.uk/hanna-digital-thermometer.html - however, with this of course you can't really leave it in the mash the whole time, which is why I like the controller with the probe.

timcunnell said:

Having said that I've just read another thread on the General Discussion forum about thermometers. Someone on there recommended this IKEA thermometer - which actually looks really good to me! http://www.ikea.com/gb/en/catalog/products/20103016/

Click to expand...

'Twas me - I really like this thermometer. Magnet on back so it sticks to shiny things, and an alarm you can set to go off when desired temp is reached. Decent length on sensor cable too.

Garethhuwwilliams said:

Something that's missing from this discussion (he said confidently) is redron's OG. Getting down to 1016 isn't of itself an indicator of low attenuation. If your starting Gravity was up around 1058-1060 you'd only be getting to 1016 with decent (75%) attenuation. Im only expecting the stout I've got on at the moment to get to about 1014 from 1057 ish, using sa-04. I've not used it before mind, so just going on fermentis' predicted 75%

Click to expand...

Good point Gareth. Should have mentioned it.
The four brews I have done with the s-04 have been two partial mashes and two AG brews. The 'biggest' I have done is the recent Theakston OP with an Og of 1052 so not that 'big'...

Redron said:

I've just tested my cheapo 5 quid digital thermometer with the probe in a pan of boiling water and it reads 93 deg, as it usually does when boiling the wort. That is way out of what it should be ! So it is quite possible I have been mashing at 7 deg too high with resulting unfermentable sugars....
Measuring temps in a bag of mash I have found to be a bit hit and miss as it can vary so much throughout 32 litres of sugary, grainy mush.
Thinking on, a thermometer is a really important bit of kit to a brewer so I guess I need to invest in a decent one.
Any pointers.... ?

Click to expand...

Yep, get a thermapen, not cheap at �£36 but they are guaranteed to be acccurate within .4 degrees.

Once I've got the mash temp right I stick one of those cheapo digital thermometers in (well the probe), ignore the fact it is showing the wrong temperature and just use it to check the temp stays the same during the mash.

Redron said:

Good point Gareth. Should have mentioned it.
The four brews I have done with the s-04 have been two partial mashes and two AG brews. The 'biggest' I have done is the recent Theakston OP with an Og of 1052 so not that 'big'...

Click to expand...

Fair dos. Brewers friend makes that 68% which isn't great but also not terrible. Though I'd not be happy with it, as I don't like treacly sweet beers.

here's the safbrew yeast properties....

http://www.thehomebrewforum.co.uk/photo/safbrew-yeast-431.html

did this with s-04...

1.8kg brewmaker ipa
1kg brewing sugar
500g dark candi sugar
500g muntons dme - medium
30g juniper berries at 15 mins
100g citra - 20g at 15 mins 80g dry hopped 5 days before bottling

OG - 1.060
FG - 1.008

So my AA was 86% - it can handle big brews.

Redron said:

Having embarked on AG brewing and bought a few clone kits, I have noticed they all come with s-04 yeast.
All the brews I have done so far with this yeast has stuck at 1016 and refuse to go lower, including some partial mash brews.
The only time I used anything different was a s-05 yeast which did get down to 1012.
From what I understand 04 yeast has a low attenuation but I would have thought it would get lower than 1016 !
All the AG kits came from the same shop and were a good price at between 11 and 12 quid. I'm guessing they have just bunged the 04 in as a 'generic' ale yeast rather than any yeast specific to the individual beers which differ wildly in taste and abv, Theakstons OP being one which is quoted at 5.7% but at the moment is only giving me 4.9 at current readings after two weeks .....
Think I need to have a read up and learn stuff about yeast !

Click to expand...

For an alternative try Mangrove Jacks M44, all the beers I have brewed with it have went to 1010 and some of those were high gravity beers in the 1060s, an amazing strain of yeast.

clibit said:

I use a glass brewing thermometer that cost about three quid. It's very accurate. I believe digital thermometers are much less so, generally speaking.

Click to expand...

Yes I have a glass one also and find it very convenient, it sits up right in the mash if I want to measure sparge temp, much more practical than the digital ones i have.

Glass thermometers have an insertion depth where they'll give an accurate reading. It's written on the thermometer somewhere. Mine is 72mm (i think)

S-04 yeast data sheet...
http://www.fermentis.com/wp-content/uploads/2012/02/SFA_S04.pdf

HebridesRob said:

Glass thermometers have an insertion depth where they'll give an accurate reading. It's written on the thermometer somewhere. Mine is 72mm (i think)

Click to expand...

Didn't know that! Thanks. Mine has no depth indication, so maybe it's a total immersion thermometer...?! I got it from a home brew shop.