Sort of Stuck Mash and Burnt Brewmonk!

Decided to cobble together a Pilsner brew that had 5kg of Pilsner malt with addition of flaked rice and Caramalt (300g each) as an experiment. I use a Brewmonk and normally mash in with 18L - the Brewmonk has 4L below the malt bin. This brew I mashed in with bit more - 19L but the mash seemed to get stuck with the recirculation going so slow it was almost stopped as the wort didn't seem to be draining.

I decided to give it a stir which helped a bit but it was still very slow. It got a lot better towards the end of the mash. Should I have used more mash water - I did read that rice was a bugger for causing a sticky mash. Was stirring the grain the right thing to get it going?

After the boil the bottom of the Brewmonk was badly burnt where the heater element is - any tips on the best way to clean that off. Was the stuck mash the cause as I have not had that happen before. Is there a way to stop the burning happening - don't fancy that sort of clear up every brew!

Thanks

David Woods said:

Decided to cobble together a Pilsner brew that had 5kg of Pilsner malt with addition of flaked rice and Caramalt (300g each) as an experiment. I use a Brewmonk and normally mash in with 18L - the Brewmonk has 4L below the malt bin. This brew I mashed in with bit more - 19L but the mash seemed to get stuck with the recirculation going so slow it was almost stopped as the wort didn't seem to be draining.

I decided to give it a stir which helped a bit but it was still very slow. It got a lot better towards the end of the mash. Should I have used more mash water - I did read that rice was a bugger for causing a sticky mash. Was stirring the grain the right thing to get it going?

After the boil the bottom of the Brewmonk was badly burnt where the heater element is - any tips on the best way to clean that off. Was the stuck mash the cause as I have not had that happen before. Is there a way to stop the burning happening - don't fancy that sort of clear up every brew!

Thanks

Click to expand...

Lemon juice always worked for me with the burnt on stuff but can't help with the stuck mash, sorry.

Cheers Tom

David Woods said:

Decided to cobble together a Pilsner brew that had 5kg of Pilsner malt with addition of flaked rice and Caramalt (300g each) as an experiment. I use a Brewmonk and normally mash in with 18L - the Brewmonk has 4L below the malt bin. This brew I mashed in with bit more - 19L but the mash seemed to get stuck with the recirculation going so slow it was almost stopped as the wort didn't seem to be draining.

I decided to give it a stir which helped a bit but it was still very slow. It got a lot better towards the end of the mash. Should I have used more mash water - I did read that rice was a bugger for causing a sticky mash. Was stirring the grain the right thing to get it going?

After the boil the bottom of the Brewmonk was badly burnt where the heater element is - any tips on the best way to clean that off. Was the stuck mash the cause as I have not had that happen before. Is there a way to stop the burning happening - don't fancy that sort of clear up every brew!

Thanks

Click to expand...

Rice hulls are a useful addition if you use sticky stuff like wheat malt, rye malt or oats.
You probably need ~ 2.7L water per kilo of grain, plus the dead space volume for mash water.

As Tom says, some sort of weak acid will help remove burnt gunk on the bottom. White Vinegar is my go to - it is in the kitchen mainly as a window cleaner, but is useful also for cleaning the last bits of gunk off the base plate an A-I-O system.

Full volume mash might help.

A good soak & Stainless scrubbies should do it. Bar keepers friend which I think its acidic too.

You could try a beta-glucan rest, 30 minutes at 40C, before the mash. I do a b-c rest whenever I use oats in a recipe as it tends to stick. Might work with flaked rice

Ferment in the kettle and let the yeast do the work.

+1 on the rice hulls. Makes a big difference to the mash permeability and also seems to increase mash efficiency. About 5% of the total grain bill works for me.

I'm afraid the only answer to the burnt bottom is lots of elbow grease. I use the nylon pads rather than stainless. Less scratches. Rice hulls should prevent this happening in the future.

Thanks for the replies and help.

Cheers

Sounds like you had a lot of flour in the grist, when an adjunct is added I stir until I feel resistance to the paddle has stopped that is when the starch has converted. Plus one for MashBags suggestion of full volume and soupdragon for the use of citrus to clean the base.
For that grist I would go between 30 and 32 litres of water.

its not the rice its the recirc.

i stopped using rice hulls and it hasnt seemed to make a difference. i would still prolly add rice if using an extra gummy grist like say oats or something.

you are circulating too fast and draining the bottom before the wort drains through the bed. this results in dry scorching.

i solved this by adding a sight glass to the run off spigot. this way you can see when the level below the tun is getting too low and you can slow down the pump. you want just enough recirc to cover the grain but not too much more or you risk scorching.


as for the scorch.

cut a lemon in half and use that as a scrub squeezuing while scrubbing. my vevor whcih is the same as the monk still has mirror like finish after a year of brewing using the lemon technique.

and plus one to what foxy said

i only stir for the first 30 mins or so after that the malt has mostly converted and you dont want to upset the filter bed once its nice and established. stirring late in the game will cloud up everything and reduce the function of the filter bed

Larse said:

I'm afraid the only answer to the burnt bottom is lots of elbow grease. I use the nylon pads rather than stainless. Less scratches. Rice hulls should prevent this happening in the future.

Click to expand...

Stainless scrubbies on stainless doesn't scratch.

David Woods said:

Decided to cobble together a Pilsner brew that had 5kg of Pilsner malt with addition of flaked rice and Caramalt (300g each) as an experiment. I use a Brewmonk and normally mash in with 18L - the Brewmonk has 4L below the malt bin. This brew I mashed in with bit more - 19L but the mash seemed to get stuck with the recirculation going so slow it was almost stopped as the wort didn't seem to be draining.

I decided to give it a stir which helped a bit but it was still very slow. It got a lot better towards the end of the mash. Should I have used more mash water - I did read that rice was a bugger for causing a sticky mash. Was stirring the grain the right thing to get it going?

After the boil the bottom of the Brewmonk was badly burnt where the heater element is - any tips on the best way to clean that off. Was the stuck mash the cause as I have not had that happen before. Is there a way to stop the burning happening - don't fancy that sort of clear up every brew!

Thanks

Click to expand...

The best way to remove burnt bottoms in all in one systems is to mix citric acid crystals at a rate of 70g to 500ml water. Boil the water and dissolve the crystals. 500ml of water is just enough to cover the bottom in my system, you only need enough just to cover it. Leave for 12 hours then use a wooden spatula, as not to scratch the metal, and scrape it off easily. Clean any residue with either barkeepers friend powder or pink stuff paste. Flour in the grain is the main culprit for stuck mash and burnt bottoms, so too are adjuncts like oat and wheat, wheat is the worst. I buy 25Kg sacks of crushed base malt, I always sieve out some of the flour, not all of it, and never have any issues with recirculation or stuck mashes.

For light cleaning, I use 'Bar Keepers Friend' (powered seems better value than liquid). It's acidic, that's meant to rejuvinate the stainless steel surface, and reduce pitting.
For a heavy burnt layer, try with boiling water, and a stiff (wooden) scraper.
Possibly with 1 Tbsp caustic soda powder if its really bad. ONLY ever, add caustic to water (not water to caustic, as that's a violent exothermic reaction).

I used to get same problem, whenever stirred a lot, even when using 10% oat hulls.
But no longer. Since switching to a regime to keep the grain bed working as the main filter, and avoiding a 'compressed grain bed'.

Stir only at dough in, just enough to break up any dough balls (which will usually float), without knocking trapped air off grains. The increased buoyancy, leads to a more open grain bed.
Leave 15-20min (G. Wheeler's advice) , for the grain to hydrate, before starting recirculation. Then recirc, at best rate that doesn’t make wort level, above grain bed, increase by more than around 2cm . Any more and the weight can compress the grain bed.

With say, a 60% wheat recipe, I'd persist with just slow recirc, if that's the best possible. A slower mash, is still much quicker than a stuck mash.

Whenever the grain bed is stirred, it frees any (previously) trapped flour and small particles. These are then likely, to mostly settle on the (heater) base below.

peterpiper said:

For light cleaning, I use 'Bar Keepers Friend' (powered seems better value than liquid). It's acidic, that's meant to rejuvinate the stainless steel surface, and reduce pitting.
For a heavy burnt layer, try with boiling water, and a stiff (wooden) scraper.
Possibly with 1 Tbsp caustic soda powder if its really bad. ONLY ever, add caustic to water (not water to caustic, as that's a violent exothermic reaction).

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Absolutely. My go to two.
And made a bit easier still with a stainless steel scrubby.

You cannot scratch something with something that is not harder. Inversely logical ss scrubbies you know what you have. Scouring pads could have anything on them, unknown hardness, unknown ability to scratch.

"Trust me on the sunscreen ". Atrrib: Bas