TETB’s Brewdays

[The-Engineer-That-Brews]

GH Oatmeal Stout​

Had a mate over yesterday to see how a brew is done. Great to see it from a newcomers eyes: the sweetness of the wort, like some kind of conjuring trick; the blast of aroma when the hops go in etc... I spared him the clean-up. Actually really helpful to have someone else's observations on the process and I'm now thinking of a few tweaks around using the pumps more rather than hoisting the kettle up and feeding under gravity.

I've not done stout before and definitely not mashed up at 67º. What with that and the 250g of rolled oats (I hope that the 'porage oats' from the kitchen cupboard was the right thing to use?) I was a bit concerned about the risk of a stuck mash. So I fed the water in from below and made it fairly wet (3.0 L/kg) but even so the sump was running a bit dry at the start. I throttled the pump and it was flowing fine after the first ten mins or so though.

I wasn't too sure about water treatment. I've read often enough that my local very hard water is well suited to stout. In the end I decided it was best not to change too many things at once and stuck with my normal regime: 50% RO, SMB, 50 mg/l CaCl, 4ml lactic in the mash and 10ml CRS in the sparge.

Grain bill (kg): 4.15 MO, 0.2 crystal 180, 0.16 choc, 0.07 roasted barley (EBC 1600 - yikes).. and a quarter of a box of what can only be described as breakfast cereal.
Hops: 34g challenger at 70, 16g challenger + 16g Goldings at flameout.

Got 26.5L into the kettle at 1.043 and took 20L into the FV at 1.049 (refrac), leaving about 3L of trub in there.
I've recently started chilling in the kettle by pumping through the counterflow, and now I can see the cold break I've become more cagey about taking it across into the FV. The jury is still out for me as to whether it makes much of a difference.

Pitched it about 5pm with S-04 which is a bit of an experiment. I love using liquid yeasts but they do cost an arm and a leg and I don't think this brew is going to be particularly short on character. Fermentation clearly underway this morning: gotta love S-04

 

[Agentgonzo]

I hope that the 'porage oats' from the kitchen cupboard was the right thing to use?

I've wondered about this when taking recipes from the internet. Normally when they ask for 4% rolled oats, I just leave them out.

I have used supermarket cornflakes in place of flaked corn (which is the essentially the same thing, except breakfast cereal has added sugar (which won't make any noticeable difference) and salt (which might, but it the qualities involved I don't think it will). I've also used shredded wheat/shreddies instead of torrified wheat for the same reason.

Take a look at the ingredients list on the back of the pack of porridge to see what's added (and the nutritional information section to get sugar/salt quantities). My guess is it's probably 100% oats, so the same thing as you'd get from the homebrew shop, just cheaper.

I know that some cereal grains may require a higher temperature (cereal mash) to gelatinise the starch, but as I understand it (I may be wrong) that's not required for wheat/oats but is for corn (but in the case of cornflakes this has been done for you by the baking process)

 

[Agentgonzo]

I've recently started chilling in the kettle by pumping through the counterflow, and now I can see the cold break I've become more cagey about taking it across into the FV.

I have a CFC to, so all my cold break ends up in the fermenter. I have had persistent chill haze that I've tried lots of things but can't get rid of. The jury's apparently out as to whether cold break in the fermentator affects taste/clarity, so I'd appreciate it if you let us know whether filtering out the cold break has any effect

 

[The-Engineer-That-Brews]

​

I have a CFC to, so all my cold break ends up in the fermenter. I have had persistent chill haze that I've tried lots of things but can't get rid of. The jury's apparently out as to whether cold break in the fermentator affects taste/clarity, so I'd appreciate it if you let us know whether filtering out the cold break has any effect

Funnily enough I've just been reading this interesting article referenced by @Sadfield in a different thread.
The 3rd experiment in particular compares the results from 'clear wort' taken from the top, versus 'stirred wort' containing all the sediment - both before and after using an immersion chiller to precipitate the cold break. He's not looking at final beer clarity as such, but he does find the clear wort comes out about 7% higher in IBUs.

My own experience is that the CFC sometimes precipitates a lot more cold break than an immersion chiller... This was the stuff left in the bottom of the kettle the other day:

Concerning the chill haze, I've read that might be due to other factors. I seem to get less of a problem with it since I started using this stuff - it's not cheap but it goes a long way (0.5ml per 20L batch)

 

[Agentgonzo]

I'm trying to eliminate all other sources in process/ingredients before adding other clarifying agents, both for simplicity and understanding the biochemistry involved. The haze doesn't actually bother me (and didn't affect the taste). But if I can't cure the haze with other methods, I'll try some of that magic jujujuice - if only as a new toy to play with

 

[The-Engineer-That-Brews]

Take a look at the ingredients list on the back of the pack of porridge to see what's added (and the nutritional information section to get sugar/salt quantities).

It says "100% Scott's rolled oats withoot anythin' added"
An interesting additive in many breakfast cereals is iron - I believe it's actually required by regulation. Consequently it's amusing to demonstrate that cornflakes are actually magnetic!

https://www.eng-atoms.msm.cam.ac.uk/VideoFolder/MagneticCornflakes

 

[Agentgonzo]

It says "100% Scott's rolled oats withoot anythin' added"
An interesting additive in many breakfast cereals is iron - I believe it's actually required by regulation. Consequently it's amusing to demonstrate that cornflakes are actually magnetic!

WTF? .

SCIENCE:. I just tried it and can confirm that a neodymium magnet does not lift a grain of Kellogg's crunchy nut off the kitchen table.

 

[moto748]

I brew oatmeal stout quite often. I've used porridge oats, and also a mixture of porridge oats and naked oats. Both have worked fine, and I have never had any issues with clarity. All that usually happens is BHE drops a little; for me, typically, from around 70% to around 65%.

I would prefer US05 or M42 to S-04, though.

 

[Agentgonzo]

WTF? .

SCIENCE:. I just tried it and can confirm that a neodymium magnet does not lift a grain of Kellogg's crunchy nut off the kitchen table.

Ok, so there's not enough iron to defeat gravity (and maybe the nuts in mine made it worse - I didn't have plain cornflakes at hand).

But this shows the effects nicely.

 

[The-Engineer-That-Brews]

I brew oatmeal stout quite often. I've used porridge oats, and also a mixture of porridge oats and naked oats. Both have worked fine, and I have never had any issues with clarity. All that usually happens is BHE drops a little; for me, typically, from around 70% to around 65%.

I would prefer US05 or M42 to S-04, though.

Useful info, thanks
Just out of interest, why not S-04? nvm - I've just remembered the discussion at S-04 yeast - funky aftertaste...?

I used to use S-04 in my early AG bitters (before I had FV temp control even) and I recall the flavour seeming very clean, if anything slightly lacking in character.
Perhaps I'm fortunately that I'm insensitive to the aftertaste some people get; or maybe the foul taste of my beer just masks it

 

[Buffers brewery]

Hi TETB. Good to see you back in the saddle

What with that and the 250g of rolled oats (I hope that the 'porage oats' from the kitchen cupboard was the right thing to use?) I was a bit concerned about the risk of a stuck mash.

I’ve brewed a couple of NEIPAs and used porridge oats instead of flaked oats. I did experience slow circulation which I blamed on the oats. So my last NEIPA brew I did a beta-glucan rest and I think it helped. The wort circulated more like normal so I will be repeating it for recipes with significant amounts of oats.

 

[The-Engineer-That-Brews]

Hi TETB. Good to see you back in the saddle


I’ve brewed a couple of NEIPAs and used porridge oats instead of flaked oats. I did experience slow circulation which I blamed on the oats. So my last NEIPA brew I did a beta-glucan rest and I think it helped. The wort circulated more like normal so I will be repeating it for recipes with significant amounts of oats.

Hi @buffers :-)
Yes I have tended to do a beta-glucan rest too but recently I've realised my brews are coming out a little dry, so I thought I'd aim for a single infusion on this one :-)

 

[RoomWithABrew]

Try the beta glucan with the oats and a little bit of malt, dough in rest as usual

 

[The-Engineer-That-Brews]

Try the beta glucan with the oats and a little bit of malt, dough in rest as usual

Genius! why didn’t I think of that?

 

[Buffers brewery]

Hi @buffers :-)
Yes I have tended to do a beta-glucan rest too but recently I've realised my brews are coming out a little dry, so I thought I'd aim for a single infusion on this one :-)

I'm probably wrong but I'd say that a beta-glucan rest shouldn't affect how dry your brew turns out. I'd suspect you're mashing a little bit too cool. Up your mash temperature by a degree or two, that might help

 

[The-Engineer-That-Brews]

I'm probably wrong but I'd say that a beta-glucan rest shouldn't affect how dry your brew turns out. I'd suspect you're mashing a little bit too cool. Up your mash temperature by a degree or two, that might help

Yep - it’s just that with a 3kW heater and a relatively slow recirculation rate my setup can only raise the mash temp at about 2°c per minute; so if I start at Beta-G temps then by the time I’ve got up to alpha amylase temps it feels like I’ve spent quite a long time in the beta amylase region…

I haven’t really done the sums, but it will be interesting to see how a single infusion compares. Fortunately on this occasion with a mash thickness of 3.0 litres per kg the flow rate was fine through the pump

 

[Buffers brewery]

Yep - it’s just that with a 3kW heater and a relatively slow recirculation rate my setup can only raise the mash temp at about 2°c per minute; so if I start at Beta-G temps then by the time I’ve got up to alpha amylase temps it feels like I’ve spent quite a long time in the beta amylase region…

I haven’t really done the sums, but it will be interesting to see how a single infusion compares. Fortunately on this occasion with a mash thickness of 3.0 litres per kg the flow rate was fine through the pump

Yes, I have similar problem/challenge with my set up so I did the B-G rest (equal weight of base malt and oats) in my fermentation bucket for 30 minutes while I got the rest of the grain and strike water ready for the mash in my mash tun. By the time I’d mashed in the remaining malt it was time to add the malt/oats. Didn’t take too long to recover temperature up to mash temperature.

 

[RoomWithABrew]

I actually use B glucanase enzyme as it's easy to get here and not too pricey. 10ml for a 25 litre batch. I add it and the oats / sticky stuff ie rye as the water is coming up to temp and hold for a while.

It did not work though the day I milled my Rye to the exact size to block every single hole in the bottom of my malt pipe. That was a painful slow mash and sparge day for sure. Lesson learnt crush my rye a lot finer. Malted oats are another option but more expensive as they have a husk ( the oat hulls ) on them. You get less extraction by weight though with these than you do with porridge oats.

 

[The-Engineer-That-Brews]

Malted oats are another option but more expensive as they have a husk ( the oat hulls ) on them. You get less extraction by weight though with these than you do with porridge oats.

Hi RwaB! You are well ahead of me in terms of your use of grains: I’ve not yet considered milling them myself. Also I’m not entirely sure what the rolled oats are intended to add to this recipe I’ve just brewed… I’m just following the GH recipe *grin*.

 

[LeeH]

WTF? .

SCIENCE:. I just tried it and can confirm that a neodymium magnet does not lift a grain of Kellogg's crunchy nut off the kitchen table.

I have worked in the factory and seen the bags of iron particles they add.