Gervin

[Meatymc]

Posted recently about using roasted wheat in a coffee vanilla stout and then using Nottingham as the only yeast I could get my hands on at short notice. Gravity stopped at 1020. Having been told Nottingham is Gervin (but twice the price) I pitched some extra yeast - Gervin - but this only got it down to 1018 after a total of 16 days. I discovered there was something amiss with my brew fridge so put this down as the reason for the high FG.

Next brew was a quick 3 gallon maris otter/northdown smash a week later to my standard recipe. As I bought more than I needed before thought I'd give Gervin a go in this one as well but, after 9 days, and despite attempts to rouse the yeast, this too has stopped at 1020.

By now, I would usually be down to at least 1010 - 1008/1010 being my regular FG although I have had a couple slightly higher but these were one-off high alcohol (7%-8%) brews.

Only similarity between the 2 brews is Nottingham/Gervin - is it known to stop early? Issue with the brew frideg resolved by the way so not a factor here.

[gr_baker]

What was your OG? Nottingham is normally a high attenuation yeast around 75-80% or more. If you're stuck on a lot less I'd wonder about your mash temperature.

[Robwalkeragain]

Quite the opposite, Nottingham tends to chew beers dry and leave them needing priming in the package. I would look at calibrating your thermometers in ice water first, might be missing mash temp, anything accidentally above 70 will cause things to get pretty unfermentable.

[Jim]

Might be worth checking your hydrometer as well while you're on.

[brewdog]

Hi
I had the same issue with gervin yeast. Spent 3weeks in the FV and still would not go below 1.028 so ended up with a sweet low alcohol wherry. I normally use SO4 which is great and quick and normally gets to my required FG

I used temp control and was disappointed.


Sent from my iPhone using Tapatalk

[Meatymc]

Thanks everyone.

Both hydrometer and thermometers checked out OK - as did the probe in the brew fridge.

OG was 1050 which is bang on for both recipes

I see mash temp' mentioned here - Jocky flagged that up on the other post I mentioned. Mash target was 68C on these last 2 brews (don't exactly know why as I'm usually 66C or 67C) and I wonder if I did let it go too high through being lax - familiarity breeds contempt as the saying goes. Don't think so but I can't be absolutely certain

Going to spend Saturday over-hauling my kit (and process) so think a thorough check on everything again and then a couple of end-to-end brews are in order - one with Gervin and the other S-05. Need to nail this as stocks are a bit low at the moment and running out of time with Xmas coming up!

[MTW]

I've mashed as high as 71, and I don't think anything as 'high' as 68 or even 70 would be enough to cause a 1.050 to stop at 1.020, unless your grist was particularly heavy on something that would raise the FG. It certainly has some effect though.

Where are you getting your Gervin from? If it's just off the shelf at room temperature in Wilkos... Only 3 gallons though, so not much for a decent yeast given good conditions.

Any chance your water calcium levels change around during the year, or your treatment changed? Just an idea.

[Meatymc]

Off the shelf at Boyes MTW - which might mean smoething to you but not anyone outside the Yorkshire/North East/Lincolnshire area. Rehydrated and plenty of 'activity' before pitching.

The stout was particularly heavy on something - roasted wheat I'd bought by mistake. I did make this clear on the other post but no-one seemed to think that was the issue.

Treatment may be a contributory factor on the 2nd brew - ran out of sulphate so only able to add 3.7g rather than the calculated 6g.

Saturday will be my 45th and 46th all-grain brews. So far I've binned only 1 through an infection, had a couple on the iffy side and a number I've not been happy with so all-in-all I'm not going to complain about a couple not reaching target given the linitations of my set-up.

I think a good clean-up, re-checking all my kit, making sure I've evrything I need in stock BEFORE I start and paying a bit more attention to each step of the process is the key here.

[MTW]

Good old Boyes's's's!

I'd ignored the roasted wheat, seeing that you had the same in the pale brew. Never used it, though I'd think it's just slightly lower for extract and needs to be in with plenty of other diastatic grains (which I assume it was).

Looks like Northallerton water is slightly higher in calcium than here (maybe ~70-80ppm?) so I don't think that will be it, by the time you put your bit of gypsum in.

Having some US-05 in the fridge at all times is a good plan, and saved me once.

Pass.

[Meatymc]

Boyes is a bit odd though. Go into the Darlington Store and they swear blind none of their stores sell homebrew ingredients. Having said that, it is Darlo!!

No wheat in this last brew - just Maris.

Scavenged Proper Job yeast is my usual 'go to' with S-05 as 2nd favourite. I usually have at least 3 samples in the fridge but had run out without realising - hence the Nottingham/Gervin. The last lot of PJ I did have didn't ferment at all - had to add a S-05 batch as well - all made up into 1.2L starters.

I did notice the dregs in the last set of 3 bottles of PJ I bought seemed a lot less than previously - wonder if they've changed something?

I chucked 5g of S-05 into the SMASH last night so will see if it's taken tomorrow.

[Kev888]

Gervin is a brand under which several yeast varieties are sold, so it doesn't necessarily mean Nottingham.
So can we double check it is the English ale yeast you are using?

[MTW]

Only time I've repitched at that sort of gravity, I got the us05 going in a small starter first, to get it used to the environment. (I don't to that at the start.) If anything, I'd put more in rather than less at this stage, but fingers crossed. That was a big beer, in which the wlp540 flaked out. A 1L active starter shaved off something like a further 8 or 9 points.

Ps Boyes is a bit of a step back in time (even in Scarborough!) but it's a very useful shop for lots of things. Where else has a homebrew dept above the habadashery and next to the DIY? Love it. I think they're still growing a little too.

[HTH1975]

Make sure you check best-before dates at Boyes - they’ve had the same out of date can of malt extract on the shelf in Northallerton for at least a year. I’ve not said anything as I’m interested to see how far out of date it will be before they remove it.

[orlando]

As this has happened with 2 different brews with the common denominator the yeast I suspect the age and storing conditions of it might be the common factor. I rarely use dried yeast for fermenting Beer but know that dried yeast to bake bread deteriorate very quickly once opened. I'm sure you didn't open yours and use it later but longer storage under ambient conditions could have had a similar effect.

[WalesAles]

Where else has a homebrew dept above the habadashery and next to the DIY?

MTW,
Wilkos in Bridgend.

WA