Bizarre experience: mash turns to milk

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They do 2 crush levels Crushed and Fine Crushed so maybe accidentally ordered wrong crush maybe
I've seen the same milkiness in the early stage of my mashes but it clears quite quickly. As others have said, probably starch that eventually converts to sugar and dissolves in the wort. As I circulate my wort through a HERMS I don't have the problem of scorching during the mash. Do you circulate the wort during the mash?
No, but I've not experienced this problem in hundreds of brews, and the strike water was heated in a separate vessel. So, I heated above mash temp in HLT to account for tempereature differentiation of the grain, mashed into the mash tun and it was milky white. Checked temp of the mash and it was at 60c, so switched on the element in the mash tun and it scorched instantly and tripped the element.

The issue was flour - the wort itself wasn't milky when settled. When I drained the wort from the mash tun into a bucket, thw flour settled out. The top inch or two was Vienna lager-coloured wort, the rest had flour settled out in it. Must have been a huge amount of flour in the bag/exceptionally fine crush, as it got through a fine mesh and the false bottom in the tun.

So the flour must have settled out at the bottom of the tun, causing the element to scorch when I switched it on.
It is sounding like it is a crush issue with excess flour. Could be it has been crushed too fine or maybe it has settled in the sack or storage container and most of the flour has congregated so when selected you have got a bad brew
I don't think it's a bad brew. Just one of those things. We all get caught out from time to time however long we have brewed and however much we think we may know.

Sorry getting all philosophical. I will go and sit in the car 😁😁
As Mashbag says usually we all suffer especially when you get to the bottom of a sack as the flour does seem to drop during transit etc and a concentrated amount of flour compared to normal. If I spot it in mine a throw in a few handfuls of oat husks
Always think it’s worth recirculating a bit before firing an element up so you get the bulk of the flour back on the top of the mash bed.

In a similar way, I divide up the sack into 4kg tubs the day it arrives. Recipes are pre-weighed, grain is airtight & flour evenly distributed.

(bird fat ball tubs)
Anyone know what might have happened here? Brewing a vienna lager this morning, mashing in with 60c strike water, and the wort turns milky instantly. Then the element in the mash tun (under a false bottom) scorched instantly and tripped out. Recipe was mainly Vienna malt, small amount of pils, bit of carapils and carafa for colour. My usual method for brewing lagers, and has never happened before!
You haven't had Jesus round, by any chance? He's renowned for that sort of thing. Bit of a party trick, but, still, don't knock it. I couldn't do it!
If there's a excess of flour in the malt, always starts with higher strike water's temperature. 65 C should be enough. And wait until the mash looks like less milky before turn the element on. Otherwise it will scorch and it's really hard to clean it up, as you experienced it.
You mentioned having a false bottom, so the advice to stir isn't going to dislodge flour once it's settled.

I've had one Weizenbock batch that burnt, in a BZ gen4. Elements had overheat cut out during boil, but managed rest of boil at reduced power.
The Weizenbock was 55% wheat malt (TMM medium crush), and being huskless there's a lot of flour. Likely much more than in Vienna.

I'd premixed all grains, with barly husks (@ 10% of wheat).
Dough in was vigorous stir, using drill paddle, recirculation from start.
It was a stuck mash, that took masses of stirring throughout.

Found a 4 to 6mm burnt layer over most of the base, with just a few clear 'channels'. I guess All the stirring had dislodged the flour and broken up the filter bed, and slow recirculation let this flour settle out on base.
Tasted discusting to me, and very nearly went down the drain. But found a friend who liked the intense smokey flavour, and took it away.

After lots of reading, I've changed my method, and havn't had problems since. Including doing that same Weizenbock recipe.

Pre-mix all dry grains
Slowly add grains, with minimal stirring to just break up lumps without knocking out trapped air. This makes grain more buoyant, and so gives a less compacted bed (which can circulate / drain faster).
Never stir again.
DON'T put in malt pipe top plate (weight compresses grain bed).
After dough in, leave for 15-20 min grain bed rest for grain & flour to hydrate (with lid on).
Start recirculation through grain bed, initially at slow rate. After a while, increase rate, till wort level just starts rising, then back it off a little.
Normally do a mashout temp step, to reduce wort viscosity for faster drain.
After mash and sparge, use malt pipe top plate to squeeze grain.

On 2nd Weizenbock attempt, only slow recirculation (and drain) was possible. Before the boil, I temporarily drained the BZ, to check there wasn't a flour build up. But this time, there were just a few very thin patches.

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