BIAB Brew, Step-by-step

[fishjam45 (Colin)]

Great guide, thanks for posting that.

[Will_D]

Re: Tannins

If you think about it squeezing spent grains is hardly likely to extract tannins!

Tannins are extracted by a fairly from a mash by a complex chemical/thermal exchange system that I don't understand or even know about!

[Garry]

Cheers Will. No need for chemical formulas, your word is enough

[LordEoin]

Yeah, i was googling it earlier and it seems to be a bit of a brewing myth.
Kind of a "i was told not to and my beer is good, so therefore it's good because i didnt" thing.
apparently your ph needs to be well off and temperatures over about 77C, and at that stage the results won't be much different between rinsing or squeezing anyway

[Sorcerers Apprentice]

Some of the big boys use mash filters which is basically a bag in a frame, and they squeeze the bejesus out of it :-)

https://m.youtube.com/watch?v=szQa9f6xBMI

[Sorcerers Apprentice]

Ps great article Garry, plus excellent idea to go up to the attic, very handy for services electric/water/waste

[Dunkel]

I'm doing some BIAB experiments at the moment. So, what would be the end difference between mashing say 5kg grain in 20l, no sparge, and diluting to 22l in the fermenter, and mashing 5kg grain in 30l, no sparge, and finishing with 22l in the fermenter? The first method seems more appealing, as you have less volume to raise to boil temperature (saving power and time), and also less volume to cool (saving water and time). I realise the hop utilization with the first method would be less, but to me this seems compensated by the choice of either adjusting to intended final volume, or adjusting to intended original gravity (if poor efficiency).

Any thoughts? 

[RichC]

Pat over on biabrewer.info has done a lot of these kind of tests with side by side brews. He refers to full volume BIAB as 'passive sparge' rather than 'no sparge' as the sparge water is used in the original volume and so is exposed to the grain. He maintains that active sparging does not improve efficiency. Personally I do full volume. I wouldn't dilute with unboiled water in the FV so I'd end up boiling the full volume anyway.

[baphomite51]

i usually aim for 23L batches with my 33l pot, so i rarely do a full volume mash ill use beersmith to calculate my mash volume and ill subtract how many litres i need so i dont have an overflow, then after my mash ill take a gravity reading and using the dilution calculator below ill calculate how many litres i need to add to reach my preboil gravity which is the most important thing. my mash effeciency is never effected my last brew i got over 80% from doing a 90 minute mash.

http://www.brewersfriend.com/dilution-and-boiloff-gravity-calculator/

[Garry]

Less than 4 weeks later