My rather crude solution is a handful of "dipsticks" made from chopsticks that I used a permanent marker to mark volumes. The chopsticks are some type of plastic-ish material (the label says "high elephant tusk chopsticks" but they are clearly not elephant tusks). I use a formula to measure out volumes, mark a few with a pencil, verify the measurements with liquid, then mark with the permanent marker. I am sure you could use a variety of materials or items for something similar. I have dip sticks for my 10, two 5 and 3 gallon pots. I have to refresh the marks now and then.Nice. I really like the SS ruler idea. Did you put in a gallon of water and use that to figure out where the mm's measured up, or did you use the formula for volume of a cylinder?
In case others didn't notice, these look like small numbers but are important. On a 5 gallon batch of beer you could be talking 1/8 gallon at mash temp and 1/4 gallon around boil. Meaning this is how much your liquid expands and fools you when you measure it for gravity calculations, deciding if you've boiled enough off, and so on.Calculated from observed values. Roughly...
Room temp to strike/mash range: +2.7%
Room temp to boil: +4%
My hydrometer came with a correction table for temps. FWIW I've been really bad about making sure all my readings are at the same temps. But I've noticed a hot sample will go up several points as it cools off.Does the expansion of water actually 'dilute' or give false readings of gravity?
I'll expand on that so it isn't confusing. I do the points thing - I don't know if it has a proper name. Let's say I want a 1.050 wort going into my fermenter and I want 5 gallons of it. 50 x 5 = 250, I refer to that as points. So that's my end-of-day target.Meaning this is how much your liquid expands and fools you when you measure it for gravity calculations, deciding if you've boiled enough off, and so on.
Let's quantify the errors from not doing the thermal expansion corrections in your example:I'll expand on that so it isn't confusing. I do the points thing - I don't know if it has a proper name. Let's say I want a 1.050 wort going into my fermenter and I want 5 gallons of it. 50 x 5 = 250, I refer to that as points. So that's my end-of-day target.
After I mash, before I boil, I want to know if what is in my kettle is going to do what I need, or if I need to modify it at all. And let's say I want to have 6 gallons in my kettle after mashing, I know I'll want a gravity for it of 250 / 6 = 42 so 1.042.
If I have "6 gallons" at 1.042, I'm good to go. But there's a catch. This is at mash temps... I need to remember that my kettle should actually show around 6-1/8 gallons, at 1.042. If I actually only see 6 gallons, since it's hot, I know I'm actually a little under target for volume.
Similar for end of boil. Let's say I want 5 gallons, cooled, in my fermenter. If I have 5 gallons in my kettle after boiling, I actually went too far. At boiling temps, the water expansion means I should see about 5-1/4 gallons in the kettle (since, when it cools, it'll just be 5 gallons).
If that made any sense at all.... it is what I mean about thermal expansion of water being important when you measure how much water you have after your mash, and how it relates to how much water you think your grains absorbed.
Does it matter? LOL. Well I have 2 different brew methods so I like to know these things so I can actually replicate a recipe between them. And my job is Process Development Engineer and so it's sort of built in for me to want to know. Not everyone will care.
I'm really interested in hearing from someone who takes accurate pre-boil volume measurements and figures accurate loss-to-grain absorption calcs. So far as I can tell, it's not obvious at all that a squeeze gives significant lautering improvement over an extended (let it hang until ~15m before flameout) gravity-only drain.
*I am not saying squeezing does any harm, I just wonder if it really adds anything worth the effort.
ETA: Speaking towards Doug's point...
That .085 gal/lb is pretty accurate whether I'm brewing my typical ~1.043 batch or an occasional 1.095 for keeping. Give or take a few thousandths of a gallon per pound. Unless I'm trying something new, like that first dry stout with a bunch of flaked barley, my pre-boil volume is very close to my expectations.
Yep! If squeezing that bag for everything it owes gives you satisfaction, go for it! If watching a bag drip for an hour is your thing, then go for it. Half of brewing is just finding a process and equipment that fits your needs and style.I guess it really boils down to what the salvaged volume is worth to you.
That's a bold assumption considering the (small amount of) data collected thus far.So if we assume around .08 gal/lb original grain absorption x 10 lbs of grain for a 5 gallon batch, and further assume we can fairly easily squeeze 1/2 the wort back out
@96Illini, please report back with your carefully measured numbers from your next batch.Now we've got...
Gravity only, in a tun or colander:
Gravity only, free-hanging:
On a rack with a little press:
Squeeze the bejeebus:
Yea, maybe it's closer to a third? But I am definitely going to do a better job recording the number. And in actual practice, I hang the bag on a pulley above the kettle while I'm heating, put my gloves on, and only give it a couple good squeezes. My mind made me think I gained a fair amount, but we shall see.That's a bold assumption considering the (small amount of) data collected thus far.
Got a Dremel?
I picked up a pretty cheap SS ruler off Amazon for just this purpose. I measure to the nearest mm which in my kettle works out to the nearest 1.something ounce.
It takes time to bring the wort to a boil. I use that time to sparge and squeeze the wort out of the bag. Total time to brew is not affected.All it gives is a bit more sugar. It takes time and my time is limited. I prefer to spend 1.5$ more in grain and not use my effeciency as a proof for my manhood.
That's my method (except the sparge part). Hoist the bag over the kettle, fire up the gas. I have 10 or so minutes to kill, so I let it drip dry a while then give it a squeeze.It takes time to bring the wort to a boil. I use that time to sparge and squeeze the wort out of the bag. Total time to brew is not affected.
After fairly close measurement on my last 10 gallon brew, with 10lbs 4 oz of grain, I recovered a little over 1/3 of a gallon of wort. This is the total recovery from the brew bag AFTER the initial removal from the pot where the bag stops dripping steadily. So after the dripping is essentially complete, and the bag is squeezed hard, I probably saved about 3 net 12 oz beers. Is all that worth it? Only you can decide, but I'll probably keep squeezing the bag pretty hard.Yea, maybe it's closer to a third? But I am definitely going to do a better job recording the number. And in actual practice, I hang the bag on a pulley above the kettle while I'm heating, put my gloves on, and only give it a couple good squeezes. My mind made me think I gained a fair amount, but we shall see.
I used some hot boiled water to sparge a BIAB one time and ended up extracting unwanted tannins. What a mistake that was.Then I hit it with a gallon of boiled water in another kettle,
Mill your grains much finer which will raise your mash efficiency, then use less grain to hit your numbers. That should lower the amount of wort left in the bag, maybe all the way down to 3 pints without squeezing.I brew 10 gallon BIAB batches usually with 25 lbs of grain in the bag.
I can let the bag hang from a pulley for 30 minutes and still squeeze an additional 1/2 gallon out of it.
No way I'm leaving 4 pints in the bag.
There is no noticeable efficiency to be gained from using the hot water and it does come with the risk of extracting tannins if your sparge water is alkaline. It only adds a few minutes to bring the wort to a boil as the hot, wet grains will heat up the room temp or cooler water to a good amount. Save yourself the extra work of boiling the water.I drain until it is down to the occasional drip, then squeeze. I just wind the hoist rope down around the neck of the bag, squeezing it tighter and tighter, then cross it for another 20 wraps or so going under the bottom, over the top. I get easily another half gallon. Then I hit it with a gallon of boiled water in another kettle, drain and squeeze again, for another gallon of goodness to boil down. Never adds any bitterness that I can detect. for 5 gallons finished beer into the keg I mash 10lb pale 2 row, 1 lb 350 choc, a cannister of quick oats and a cannister of yellow grits at 150f one hour with a half hour cooldown cycle, for reference.