Squeezing the Bag

[ZmannR2]

So I've been brewing about 6 months now, I'm about 7 mini mash batches in and have always had excellent results and crystal clear beers (after cold crashing and kegging) and have always read to never squeeze the bag.

BIAB is my future, I'm building an electric set up and in my research I keep seeing the phrase "squeeze the bag". What gives?? I thought that was a no no!

Also, looking into my calculations of boil off rate and grain absorbtion. Are these good numbers?

.045 Gallons/Pounds of grain w/o squeezing
.031 Gallons/Pounds of grain with squeezing
1.25 gal/hr boil off time (11 gallon pot boiling roughly 7.5 gallons)

I'm in South Texas at Sea Level

Who has values above/below these numbers? Being my first BIAB, should I shoot for lower numbers and just top off the fermenter in the end and adjust on the next boil?

 

[20grit]

If you're using a coarse mesh bag, squeezing could introduce a lot more sediment into your wort. The finer mesh bags (like wilserbrewer's) should allow less stuff out during a squeeze.

In my squeezing, I haven't over-squeezed at any point. I just squeeze enough to get some liquid moving. Then relocate to another spot on the bag, squeeze again. Once it gets really slow, I might squeeze a bit harder, but I've not seen a lot of sediment come out at that point.

 

[GrogNerd]

think it's more a NO-NO when it's just specialty grains

 

[barnaclebob]

i squeeze as hard as i can and get about .25 qts/lb (or whatever unit of measurement brewtarget uses).

 

[doug293cz]

So I've been brewing about 6 months now, I'm about 7 mini mash batches in and have always had excellent results and crystal clear beers (after cold crashing and kegging) and have always read to never squeeze the bag.

BIAB is my future, I'm building an electric set up and in my research I keep seeing the phrase "squeeze the bag". What gives?? I thought that was a no no!

Also, looking into my calculations of boil off rate and grain absorbtion. Are these good numbers?

.045 Gallons/Pounds of grain w/o squeezing
.031 Gallons/Pounds of grain with squeezing
1.25 gal/hr boil off time (11 gallon pot boiling roughly 7.5 gallons)

I'm in South Texas at Sea Level

Who has values above/below these numbers? Being my first BIAB, should I shoot for lower numbers and just top off the fermenter in the end and adjust on the next boil?

Squeezing is fine. There are commercial breweries using hydraulic filter presses, which squeeze much harder than we can with our hands.

Your grain absorption estimates are way low. More realistic values are 0.09 - 0.10 gal/lb w/o squeezing, and 0.06 - 0.08 gal/lb with squeezing. The lowest credible number I've seen for hand squeezing is about 0.055 gal/lb.

1.25 gal/hr boil off is well within the reasonable range. You should do a test boil with water on your system to get an initial estimate, and then fine tune when you boil actual wort.

Brew on

 

[GHBWNY]

Squeeze away. I used to believe it would cause extra astringents/tannins in the wort. Pfft. Old wive's tale. It will increase sediment, all of which is going to settle out anyway. But getting all the delicious wort out of the grain is a must (npi).

 

[ScrewyBrewer]

Squeeze away. I used to believe it would cause extra astringents/tannins in the wort. Pfft. Old wive's tale. It will increase sediment, all of which is going to settle out anyway. But getting all the delicious wort out of the grain is a must (npi).

Agreed, right up there with hotside aeration and not double crushing your grains, which I always do. My advice is just squeeze all of the wort you can out of the grain and then top off the kettle to hit your pre-boil volume.

It's way easier to just calculate your boil off per hour and the amount of wort lost to kettle trub and lines.

1.25 gallon boil off per hour
0.50 gallon kettle trub loss
0.25 gallon lines and pump loss
------------
2.00 gallons total wort loss
5.25 gallons into the fermentor
------------
7.25 gallons pre-boil volume

Of course the more often you brew the better idea you'll have as to wort loss and the more accurate you'll get to filling your fermentor.

 

[Ungoliant]

Squeeze that bag like it's late on protection money, and you're choking the payments out.

 

[PADave]

Of course the more often you brew the better idea you'll have as to wort loss and the more accurate you'll get to filling your fermentor.

The first BIAB or two I used some numbers and got close. Just keep good notes and you'll soon be able to calculate your water volumes accurately. And squeeze away.

 

[myelo]

Squeeze that bag like it's late on protection money, and you're choking the payments out.

Hanging upside down for a while over a vat of hot liquid is also pretty effective at convincing it to pay up. That is, if you have a pulley you can just hoist up the bag and let it drip into the kettle for 10 minutes or so. Sometimes I tell it I know where it's momma lives to speed up the process.

 

[casualbrewer]

I do full volume boil with no sparge biab. However I get my lhbs to double crush my grain and I squeeze the bejeezus out of the back. Just got 84% brewhouse on my last batch...

 

[petrolSpice]

I spend a few minutes squeezing and get roughly 0.06-0.08 lb/gal absorption.

 

[ZmannR2]

Thanks so much y'all

 

[kh54s10]

The fear with squeezing was the theory that you would extract tannins and add astringency. That has been petty much debunked. It takes temperature and a certain pH level that you are very unlikely to meet doing a homebrew.

Squeeze it.

 

[Murphys_Law]

I took a class last year (its how I got into home brewing) and the instructor put the fear of God in me re squeezing! Hell, I was afraid to look at the bag for too long because I thought it might hurt my beer!

I now squeeze that sucker like it stole money from me!

 

[Rye-guy]

I'm guilty of squeezing the bag on occasions. Only after I sparge though.

 

[doug293cz]

I'm guilty of squeezing the bag on occasions. Only after I sparge though.

It's better if you squeeze before sparge. You get more of the good stuff out that way.

Brew on

 

[wobdee]

I squeeze but I don't sparge. I probably wouldn't do it if I sparged. After a sparge your PH may be out of whack and give you tannins?

 

[doug293cz]

I squeeze but I don't sparge. I probably wouldn't do it if I sparged. After a sparge your PH may be out of whack and give you tannins?

Depends on your water's alkalinity and how much you sparge. Just acidify your sparge water to pH 5.8 or a little lower, and there is no way you can sparge your way to tannins. You also get more sugar (higher efficiency) by squeezing before the sparge than squeezing after.

Brew on

 

[Willy_Liverdye]

I'm a bagless extract brewer. I dump my specialty grains in 150-155deg water stir occasionally, pour it through a SS strainer into my boil pot, and strain again from pot to bucket for cooling

 

[austin713]

I'm a bagless extract brewer. I dump my specialty grains in 150-155deg water stir occasionally, pour it through a SS strainer into my boil pot, and strain again from pot to bucket for cooling

why not just steep in a muslin bag and discard when youre done?? that seems like alot oof work.

 

[potseeslc]

Here is a link to the calculator I use feel free to copy it. I squeeze really hard and it hits my numbers pretty well. https://docs.google.com/spreadsheets/d/15GRihejTkN0rgrXlFxpBugsVlUSdrZPXQWZmFrnZEhw/edit?usp=drive_web

 

[Bigarcherynut]

I also did a lot of reading about squeezing. I ended up making this squeeze board setup and it saved my hands and arms. I squeeze like a mad man.

 

[applescrap]

Squeezing is fine. There are commercial breweries using hydraulic filter presses, which squeeze much harder than we can with our hands.

Your grain absorption estimates are way low. More realistic values are 0.09 - 0.10 gal/lb w/o squeezing, and 0.06 - 0.08 gal/lb with squeezing. The lowest credible number I've seen for hand squeezing is about 0.055 gal/lb.

1.25 gal/hr boil off is well within the reasonable range. You should do a test boil with water on your system to get an initial estimate, and then fine tune when you boil actual wort.

Brew on

I love to talk about squeezing my sack. It can be hard when the bag is big. I need to set up the pulley. Doug you gave me these numbers a while ago and they didn't make sense to me and they are starting to, thanks. I think I'm closer to .05. I pull the bag, and put in an 8 quart strainer. You know the kind you get with a pot when you get married. I put that over a five gallon food safe Home Depot bucket and use a small pot lid that fits just inside it. Then as others have said I get to it like it owes me money. Over time I realized those last two pints of wort probably aren't worth it, but they are also super dark.