Hi all,
We've been experiencing some turbidity mysteries during lautering. Somewhere during the process, turbidity seems to increase greatly and I don't understand why.
The problem is mostly when we brew our low gravity beers (around 11P) and most apparent when brewing our beer that has a malt bill made up of 30% corn flakes. In our 40hL brewing system, we always see a big drop in clarity after about 20hL of wort has been pumped to the brew kettle and it usually results in having to mix up the grain bed, start vorlauf again, which takes about 45 minutes before a proper clarity is reached again.
We have a lauter tun and software designed for batch sparging (don't ask me why). The corn flake beer wort is mashed in in a 1:3 ratio with 19,5 hL water (so we use 650kg of malt/corn). First sparge is after 11hL of lautering. By that time there's still a bit of wort on top of the bed. Lautering keeps going after each sparge (5 sparges in total, each half the volume of the one before. I'm not sure about the theory behind this, please enlighten me if you do know), we usually don't do or need to mix and recirculate, the idea behind it that we don't mix the wort as much as 'replace' it from the top down with lesser strength wort. We rake about 5cm above the false bottom at a very slow speed during the process.
It seems to have something to do with the thickness of the bed, since our higher gravity beers (usually between 15 and 18P), don't exhibit these problems to this extent (in all fairness, there usually does seems to be a smaller drop in clarity around the 30hL mark).
Some extra or maybe redundant info: the corn flake wort get's a 90 minutes step mash, including 20 minute beta-glucanase rest at 45 degrees Celsius. Lauter tun diameter is 3m. The top of the filterbed of the corn flake wort looks quite solid and cake-y.
One theory so far: finer particles that settles on top of the filter bed migrate down at some point and find their way through the false bottom. But why?
Pardon my metric. And thanks in advance.
We've been experiencing some turbidity mysteries during lautering. Somewhere during the process, turbidity seems to increase greatly and I don't understand why.
The problem is mostly when we brew our low gravity beers (around 11P) and most apparent when brewing our beer that has a malt bill made up of 30% corn flakes. In our 40hL brewing system, we always see a big drop in clarity after about 20hL of wort has been pumped to the brew kettle and it usually results in having to mix up the grain bed, start vorlauf again, which takes about 45 minutes before a proper clarity is reached again.
We have a lauter tun and software designed for batch sparging (don't ask me why). The corn flake beer wort is mashed in in a 1:3 ratio with 19,5 hL water (so we use 650kg of malt/corn). First sparge is after 11hL of lautering. By that time there's still a bit of wort on top of the bed. Lautering keeps going after each sparge (5 sparges in total, each half the volume of the one before. I'm not sure about the theory behind this, please enlighten me if you do know), we usually don't do or need to mix and recirculate, the idea behind it that we don't mix the wort as much as 'replace' it from the top down with lesser strength wort. We rake about 5cm above the false bottom at a very slow speed during the process.
It seems to have something to do with the thickness of the bed, since our higher gravity beers (usually between 15 and 18P), don't exhibit these problems to this extent (in all fairness, there usually does seems to be a smaller drop in clarity around the 30hL mark).
Some extra or maybe redundant info: the corn flake wort get's a 90 minutes step mash, including 20 minute beta-glucanase rest at 45 degrees Celsius. Lauter tun diameter is 3m. The top of the filterbed of the corn flake wort looks quite solid and cake-y.
One theory so far: finer particles that settles on top of the filter bed migrate down at some point and find their way through the false bottom. But why?
Pardon my metric. And thanks in advance.
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