biab

Make grain beers with the absolute minimum of equipment. Discuss here.
sam51
Tippler
Posts: 11
Joined: Sat Dec 01, 2018 4:42 pm

biab

Post by sam51 » Tue Apr 02, 2019 10:07 pm

hi all need a bit of advice, i made a b i a b a week ago,
started at 1060 its is now 1030, i think i made a mistake
at rehydrating the yeast, i had 11grams of yeast, nottingham, but mixed it with 250mm of water, instead of 100mm, dont think it will go down any more,
so do i put more yeast in and get a yeast nutrient , or do i leave it ,
bit annoyed i made a simple mistake.
thanks sam.

User avatar
Jim
Site Admin
Posts: 10250
Joined: Sun Aug 22, 2004 1:00 pm
Location: Washington, UK

Re: biab

Post by Jim » Wed Apr 03, 2019 7:52 am

Nottingham is usually pretty good and though you might have damaged a few cells it should still be OK.

Fermentation time depends on the temperature and also your OG was fairly high, so give it a chance - it can take a couple of weeks depending on the conditions.

I would check the gravity again in a couple of days and see if it's still going down before adding anything.
NURSE!! He's out of bed again!

JBK on Facebook
JBK on Twitter

User avatar
Kev888
So far gone I'm on the way back again!
Posts: 7701
Joined: Fri Mar 19, 2010 6:22 pm
Location: Derbyshire, UK

Re: biab

Post by Kev888 » Wed Apr 03, 2019 9:18 am

Unless the rehydration water was too hot, the yeast shouldn't have suffered too badly from the extra amount. As Jim says, the fermentation might be just taking a while, and still be working away. Or there might be other things behind it (such as with the mash).

What kind of temperature is it fermenting at, and what is the volume of wort?
Kev

User avatar
helmetHeid
Tippler
Posts: 28
Joined: Sat Nov 10, 2018 12:16 pm

Re: biab

Post by helmetHeid » Thu Apr 04, 2019 1:31 pm

Would agree with Jim that it might just take a bit more time.

Another option is that maybe your mash temperature was a little high. This would mean you ended up making a wort that's less fermentable and would end up with a high final gravity. Just one possible option.

steviebobs83
Piss Artist
Posts: 172
Joined: Tue Mar 06, 2018 10:19 am

Re: biab

Post by steviebobs83 » Thu Apr 04, 2019 9:13 pm

What are you using to take gravity readings? If it's a refractometer, you'll need to correct for alcohol present.

Have you tasted a sample?

sam51
Tippler
Posts: 11
Joined: Sat Dec 01, 2018 4:42 pm

Re: biab

Post by sam51 » Sat Apr 06, 2019 12:03 pm

so the beer is still 1030, started at 1060,
have now transferred to secondary , smells ok,
i used 5 kg of marries otter, is that the reason i had a high starting sg.
but by using 5 kg, do i get a better efficiency ,
i think achohol will be around 5% is this right.
may use 4 kg next time?
thanks.

sam51
Tippler
Posts: 11
Joined: Sat Dec 01, 2018 4:42 pm

Re: biab

Post by sam51 » Sat Apr 06, 2019 12:06 pm

I'm using a wilko hydrometer, reading taken at around 24 degrees start
and around 22 finish.in the primary ,

steviebobs83
Piss Artist
Posts: 172
Joined: Tue Mar 06, 2018 10:19 am

Re: biab

Post by steviebobs83 » Sat Apr 06, 2019 12:34 pm

I've never used Nottingham myself but 22-24°c sounds a touch on the high side for a good ferment. That may have contributed to the under-attenuation.

User avatar
helmetHeid
Tippler
Posts: 28
Joined: Sat Nov 10, 2018 12:16 pm

Re: biab

Post by helmetHeid » Sat Apr 06, 2019 12:41 pm

Any idea what temperature you mashed at?

And was the temp good and stable throughout the mash (and is your thermometer working ok?)

User avatar
Kev888
So far gone I'm on the way back again!
Posts: 7701
Joined: Fri Mar 19, 2010 6:22 pm
Location: Derbyshire, UK

Re: biab

Post by Kev888 » Sat Apr 06, 2019 1:14 pm

The fermentation temperature is a tad higher than normal but nothing that should have troubled the yeast much. That level of attenuation is very little for nottingham, and it is normally very reliable, so to have stuck there suggests something has gone fairly wrong, unfortunately.

That is assuming the hydrometer readings are correct, of course - tasting can help with a crude check; it should still be quite sweet at 1.030. Also test the hydrometer in water; it should be about 1.000

The mash might also be a culprit. If it were somewhat too warm, then the type of sugars produced would be harder for the yeast to use so the gravity will stay higher. Or if it was much too warm then the enzymes would have been be denatured and they wouldn't have converted the starch to sugars properly, so again the yeast will struggle to use it.

1.060 isn't massively high, well within what Nottingham should handle. But it is reaching the point where the yeast have more to cope with; quite often manufacturers recommend two packs to be used at around that kind of gravity. So if the yeast were affected by something else too, such as being rehydrated too warm, or excessively long/hot storage, then they could well have been under strength.

You might pitch an extra pack or two just to see if it revives things. It won't make up for a dodgy mash but might help if the yeast were the cause in some way. Gervin ale yeast (called English ale yeast at Wilkos) is a budget alternative to official nottingham, which might make the uncertainty of success less expensive.
Kev

sam51
Tippler
Posts: 11
Joined: Sat Dec 01, 2018 4:42 pm

Re: biab

Post by sam51 » Sun Apr 07, 2019 9:35 am

i am pretty sure the mash temp was 72 to 74c , ill et you know what it taste like.
many thanks.

steviebobs83
Piss Artist
Posts: 172
Joined: Tue Mar 06, 2018 10:19 am

Re: biab

Post by steviebobs83 » Sun Apr 07, 2019 9:42 am

sam51 wrote:i am pretty sure the mash temp was 72 to 74c , ill et you know what it taste like.
many thanks.
Yeah that's rather high. Somewhere in the mid 60's will make a more fermentable wort.

User avatar
helmetHeid
Tippler
Posts: 28
Joined: Sat Nov 10, 2018 12:16 pm

Re: biab

Post by helmetHeid » Sun Apr 07, 2019 9:49 am

Here's a chart showing the different mash temps. You're a bit high for the different enzymes to do their work[IMG]//uploads.tapatalk-cdn.com/201904 ... e0b12c.jpg[/IMG]

User avatar
helmetHeid
Tippler
Posts: 28
Joined: Sat Nov 10, 2018 12:16 pm

Re: biab

Post by helmetHeid » Sun Apr 07, 2019 9:57 am

Normally you'd have a mash temp that can hit both the beta and alpha amalase enzymes. So yeah, somewhere in the mid 60s would be ideal

User avatar
Kev888
So far gone I'm on the way back again!
Posts: 7701
Joined: Fri Mar 19, 2010 6:22 pm
Location: Derbyshire, UK

Re: biab

Post by Kev888 » Sun Apr 07, 2019 11:10 am

That might well be getting down to the cause; 72c is fairly high even if purposely trying to limit attenuation, but 74c is becoming too much really. Especially if variation in the mash could have made some parts warmer than was appreciated at the time, and/or if it started higher and took a while to bring down to that temperature.

In a similar way to the hydrometer, it is probably also worth checking your thermometer - e.g. in iced water and boiling water (if it can take the latter safely). Some of them can be out by a couple of degrees quite easily.
Kev

Post Reply