BIAB/MIAB bag not draining

[dave_h]

I am currently mashing in a bag (swiss voile) in a coolbox. I have a plastic sheet with holes in that the bag sits on keep the bag off the bottom of the cooler to help it drain.

My problem is that sometimes the bag refuses to drain, even when i lift the bag it wont drain.

Last time i had to remove all the grains, wash the bag and use rice hulls but even then it was very slow.

It does not however seem consistent, sometimes it drains very easily even with high wheat concentrations.

Im opening the tap slowly.

My grain is set to 0.6mm.

Does anyone else have this issue? Im thinking of adding a pulley system or a better way of keeping the bag off the bottom.

 

[mtb]

Is there any reason you're milling so fine? 0.6mm is pretty narrow in some cases.

 

[dave_h]

I have had pretty lousy efficiency so I have set the mill to grind quite fine. A fair few people suggest 0.6mm was ok for biab.

There does not seem to be too much flour but i suppose this could be it. Its just not consistent. I can always open it upto 0.9mm and see if that makes a different. And double mill.

 

[captain crumpet]

With biab my efficency always improves with a finer milling.

Your procedure is a double filter. You are draining past a grain bed and a filter bag. I could only picture a struggle. Improving efficiency with biab includes lifting and squeezing. I have never had issues reaching post mash volumes and can always get a little more volume than targeted if i needed or wanted.

I think you need to pick between one way or the other.

 

[Lionman]

I struggled with this on one of this weekend brews. I find its worse when I use wheat malt in the grist. The brew that stuck was 40% wheat 60% Vienna. The brew I did the day before that was 90% pils and 10% Munich, it lautered and sparged like a champ.

It was a colossal pain in the backside, I ended up needed to double sparge to get to 66% mash efficiency and it tooks hours to boil off the excess.

 

[Beamer]

I use an esky and a custom built bag available online from the states. ( pm me for website not sure it right to post it) effiency went from 66 to 73 and i mill at .6 aswell

 

[bcp]

I use a colander in the bottom of my urn to keep the bag off the element. When I pull the bag out, I drop the colander in my big bucket, and put the bag on top. Meanwhile I can heat it up to the boil while the bag drains in the bucket. I add it later in the boil.

I have a second bucket that I sometimes put on top of the bag in the bucket and press down to squeeze more out of the bag.

 

[Nizmoose]

You could give it a 10min rest at 45c ish at mash in if you think the breakdown of any glucans might help wort separation assuming it's not just a simple physical mill setting issue

 

[Bribie G]

Did you get your voile from Spotlight? Apart from once when I used flour as an adjunct I've never had a stuck mash. Maybe voils ain't voils.