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In one of the earlier BIAB threads (sorry, so many of them I can't recall which one), someone had come up with a small gantry type arrangement to sit over their brewing vessel, so that the bag could be tied up to it to be held above the liquid. This could be made of wood or tubing of some sort, and be able to be somewhat disassembled for ease of storage. Although a pulley isn't essential as noted by many posters here, it is nice to have the ability to raise the bag above the vessel to let it drain while the wort is being heated up for mashout for example. Perhaps a gantry of some sort might be an alternative for those living in an apartment?

Off topic somewhat, I am becoming a fan of lots of stirring during BIAB mashing, as my gravity readings have been very low compared to expected readings. Thought it over a fair bit and have come to the conclusion that I might only be extracting sugars from the grain on the outside of the bag if I just use the dunking technique to agitate the mash. My next one will just be done with lots of stirring and no dunking to see how it compares. Having said that, I am still very impressed by the beers I have been making, and look forward to being able to improve them by not needing to have LDME on hand to boost the gravity of the wort.

cheers,

Crundle
 
Thirsty Boy, I actually had an idea and searched for images of cake racks, and came across this post you'd made on another forum!

http://www.thebrewingnetwork.com/forum/vie...&start=0/fa

You know the false bottom you've used, what if your bag was actually stitched to that, and then you had say 4 ropes also tied to the the rack at equal distances on the edge. Then if you had a bigger cake rack (that was bigger than the diameter of the kettle) you pulled the false bottom up into using the ropes, affectively squeezing the bag between two metal racks. May be a good option for people that can't use pullies and don't want to just pull the bag out, and the bottom cake rack could have legs on it so that the bag never touches the bottom of the pot.

Thoughts?
 
Hey mark, except for the top "grill", that is exactly my idea, but just letting gravity do the work.

ED: I figured 4 hoisting points and I thought 4 pieces of metal bent into hooks to hold the base at a specific distance from the top of the kettle.
 
Would you lift the bag up then hook the bottom grill onto some hooks that were attached to the side of the pot? Not a bad idea.

Again I'd like to have some data on efficiency differences between just draining, vs squeezing, etc. Cause if there's not much in it you may as well drain while you're waiting for the wort to boil.

Interesting though in that link it mentions hot side aeration when the bag is draining. It mentions leaving the bottom part of the bag in the wort while draining to minimise hot side aeration. Something else to think about I guess! How long is a piece of string again?
 
In one of the earlier BIAB threads (sorry, so many of them I can't recall which one), someone had come up with a small gantry type arrangement to sit over their brewing vessel, so that the bag could be tied up to it to be held above the liquid. This could be made of wood or tubing of some sort, and be able to be somewhat disassembled for ease of storage. Although a pulley isn't essential as noted by many posters here, it is nice to have the ability to raise the bag above the vessel to let it drain while the wort is being heated up for mashout for example. Perhaps a gantry of some sort might be an alternative for those living in an apartment?

Off topic somewhat, I am becoming a fan of lots of stirring during BIAB mashing, as my gravity readings have been very low compared to expected readings. Thought it over a fair bit and have come to the conclusion that I might only be extracting sugars from the grain on the outside of the bag if I just use the dunking technique to agitate the mash. My next one will just be done with lots of stirring and no dunking to see how it compares. Having said that, I am still very impressed by the beers I have been making, and look forward to being able to improve them by not needing to have LDME on hand to boost the gravity of the wort.

cheers,

Crundle

You almost certainly will get better efficiency with stirring rather than dunking - one of the things that has been emphasized on numerous occasions in BIAB discussions - is that the bag should in no way restrict the mash - you are NOT mashing in a bag, you are mashing in a pot. The bag should line the pot and not affect the mash, the way the grain settles or sits or circulates in any way at all. The mash part of BIAB should proceed as though the bag was not there at all. Hence the idea of the bag being bigger than the pot.

The bag only comes into play, after the mash is over and done with - maybe you use it to raise the grain off the bottom while you add heat to get to a sparge/mashout temp, maybe you dont even do that. The bag is for lautering - it should have nothing to do with mashing at all.

Mark - that sounds workable enough. It would probably work - I still cant see why you would actually want to do it that way - but if you want to... why not. It does sound like something that might have a good chance of getting tangled or something getting stuck and everything ending up lopsided, but a bit of care and it could be a goer. Maybe better with loops sewn into the bag - like those self squeezing teabags. Rack sits on the bottom (unattached to bag) then bag self squeezes as it is pulled out by the drawstring....

I wouldn't stitch the bag to the rack because that would interfere with squeezing for me - you would then be "forced" to squeeze only in the horizontal plane (either by your ropes and racks or by another way) because sideways squeezing would tear your bag off the bottom rack.

Tea is a good example here - think giant tea bag. There are tea balls, tea pots that are like coffee presses, standard tea pots, strainers, steepers etc etc - but what do most people actually do?? They drop in a teabag, jiggle it round for a while, pull it out and give it a squeeze between a couple of spoons

Squeezing the bag is going to make a difference thats fairly easily calculated. You squeeze - you lose about 0.5L of wort to grain absorption per kg of grist. You dont squeeze and that goes up to around 0.75 L/kg - So roughly 250ml of wort per kg difference. With 4kg of grain, thats a litre of wort that doesn't make it into your kettle, and thats from 3.5-4% of your extract. More than 4kg of grain... then it gets worse.

You can squeeze the bag perfectly well without a pulley - pull the bag up, hold it up for 10-15 seconds to drain - throw it in a bucket - Turn on your flame - take bucket and bag to nearest door - pull up the bag so its half out of the bucket and wrap the string around the door handle to hold it there - drain for a while - tip contents of bucket into kettle - put bucket back under bag, take two saucepan lids and squeeze bag between them - tip resulting liquid back into kettle - done

Some people get a big colander - pull the bag out - whack the colander over the pot - drop bag in. When it stops dripping, then push on it to squeeze. Your "upper" big rack would serve the same purpose. Just pull the bag and sit it on top of the rack for draining and squeezing.

HSA avoidance by leaving the bag in contact with the wort.... if you do have a pulley and can suspend the bag, then you can hang it to drain directly over the kettle. If you leave a tiny patch (say the size of a 50c piece) in contact with the surface of the liquid, then the wort draining from teh bag "flows" down rather than drips or splashes - you are only talking for the first minute or two, then you just hoist it up so it drains all the way out before squeezing (if you want). Not really an issue in my book, but its easy enough to do, so why not play it safe and avoid the splashing.

TB
 

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