Stepped mash using Crown urn BIAB - ashtray flavour

[hobospy]

Not brewed in a while (guessing about a year) but had my first attempt at the Bullheads Kolsch recipe. The recipe calls for a three step mash, mash in at 52, then raise to 64, raise again to 71 and then mash out. I'm using a Crown urn so I followed the advice in the thread on mashing in slightly thicker at 52 and then raising to 64 using boiling water which seemed to work OK. I then started to raise the temp from 64 to 71 ten minutes early to allow the urn time to ramp up (again mentioned in the thread). After the ten minutes were done I ramped up to boiling temp and removed the bag just after the temperature reached 78C. The first point at which I thought something may be up was how long it took to boil (I put this down to my recirc) but also how light the boil was, I've only seen this once before when I attempted a rye beer. Anyway, to cut a longer story shorter, I completed the brew, chilled and transferred it at which point I noticed a small amount of grist flour burnt to the bottom of the urn, my first taste from the fermenter (SG was about 1020) wasn't too bad, just tasted sweet as expected, maybe a bit thick too, the second one just taken on the weekend was still a bit full, nice flavour, great colour but definitely with a slight ashtray flavour to it. After reading a few guides on what off flavours were I think this is down to the scorched grist.
[TLR] Attempted to brew kolsch recipe in Crown urn using stepped mash from 52 - 64 (boiling water addition) and 64 - 71 (electric element) and seem to have picked up an ashtray flavour which I am putting down to the scorched grist stuck to the bottom of the urn.

So four questions:
1. How do people with Crown urns manage stepped mashes?
2. Am I right in assuming that it is down to the burn grist, have searched on here too and think it is the best match.
3. From what I have read I am going to have to live with the flavour, does it dissipate at all
4. First time getting my grain milled at the local HBS and concerned it may have been milled a bit fine resulting in a lot of flour

System configuration:
40l Crown urn with concealed element
SS false bottom (wonder if this restricted the wort movement directly above the element which is why it burnt)
CraftBeerPi temp controller (temp measured on exit of urn using DS18B20)
Recirculated wort throughout brew to try to clear it up (understand people are able to do this by lifting the bag very slowly)

Thanks for any advice.

 

[malt junkie]

the best way to do this, is what Qldkev did. From your description you have a recirc system already in play, what kev did was to direct part of this flow under the FB directly at the element, specifically to avoid the scorching issue.
Try searching recirculating biab if what I've said is unclear.

 

[hobospy]

Thanks, I was wondering if I should do that, my only concern was whether this will result in more trub making it through to my fermenter (probably not an issue). I've also raised the FB with SS bolts for the next attempt, I will reattempt the kolsch to see if I can get a cleaner flavour.

 

[Rocker1986]

I tried a couple of step mashes in my urn a couple of years ago, and never again since. I tried one without the false bottom and one with.

I didn't get an ashtray flavor but the low temp rests did result in a lot of shit build up on the element cover, which caused it to cut in and out trying to heat it as well as boil it.

In my case I started at 40 degrees and didn't use boiling water to increase temps in the first couple of ramp ups, so a bit different.

I've since just used hochkurz mashes starting at 63 with great results and no issues heating and boiling.

 

[hobospy]

Thanks for that Rocker, do you stir whilst raising the temps? My temperature adjustments with the urns element would be relatively similar as I used boiling water to get from 52 to 64. I was hoping that the recirc would draw wort away from the element area to stop anything sitting on it and burning and remove the need for me to disturb the mash. Do you mill your own grain? Concerned this may have been too fine resulting in a lot more flour, read a few BIAB posts around and I'm starting to think that I might just ask for a standard mill next time to try and reduce the amount of flour.

 

[Rocker1986]

I do stir while raising the temp but not continuously. I just give it a few intermittent stirs while it rises.

I mill my own grain yes, quite coarse with little flour. I've found this to work better than a finer crush for both efficiency and wort draining from the bag.

I also have a stainless wire brush on a long handle that I use to clean off the element before I begin bringing it to the boil. It may not be necessary but I don't get any cut outs. There is muck on the element afterwards but it's not really blackened or anything.

 

[hobospy]

Thanks for that, I'll try stirring on ramp up next time to see if that resolves the problem and then maybe look at QLD Kev's base wort return too.

 

[stm]

As I have said before: for the vast majority of beer styles and for beginner to intermediate brewers, a step mash will have virtually no detectable effect on the finished beer at the home brew scale. (Therefore, you are complicating and lengthening your brew day for no reason.)

 

[manticle]

Depends entirely on the steps.

Quite a few have a distinct and noticeable effect and you don't need to be a beer genius or Commercial Brewery to notice.

However step for a determined reason and effect or just go single infusion as modern 2 row malts are generally well suited to SI.

Protein rests tend to burn on urn elements.

 

[Ducatiboy stu]

I mill my own grain yes, quite coarse with little flour. I've found this to work better than a finer crush for both efficiency and wort draining from the bag.

Thats interesting and very important. With a false bottom and recirculating sparge I found 25-30% flour worked well ( I also grain wetting/conditioning helps to keep whole husks in the mash )

 

[Bribie G]

Before I had a mill, I used to get my grain from Craftbrewer in 5kg lots - for the discount - and on a couple of occasions Anthony was kind enough to do a finer crush to test out the BIAB crush theory thingo.
Didn't notice much of a difference in efficiency.

 

[Black Devil Dog]

I do stir while raising the temp but not continuously. I just give it a few intermittent stirs while it rises.

I mill my own grain yes, quite coarse with little flour. I've found this to work better than a finer crush for both efficiency and wort draining from the bag.

I also have a stainless wire brush on a long handle that I use to clean off the element before I begin bringing it to the boil. It may not be necessary but I don't get any cut outs. There is muck on the element afterwards but it's not really blackened or anything.

I used to do a similar thing, but instead cable tied a s/s scourer to a cut down broom handle.
Worked a farking treat.
Often did stepped mashes in my urn.

 

[Rocker1986]

I used to do a similar thing, but instead cable tied a s/s scourer to a cut down broom handle.
Worked a farking treat.
Often did stepped mashes in my urn.

I thought about something like that too but ultimately decided on the brush. It works great, but yeah the only stepped mashing I do now is the hochkurz mashes, although I do a short rest at 72 for all beers now. I read somewhere that it helps with head retention, and I have noticed improvement in that and lacing down the glass. Could be coincidence too I guess.

 

[hobospy]

Thanks for all the replies. The main reason for me stepping the mash was because the recipe asked for it and my first time brewing this recipe so thought I should try and keep it as close to what was asked for as possible. May have to also look at the SS scourer/brush approach.