Need a new sparging technique

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David_Trucks

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I do BIAB and my gravities are always a bit low. Did a DIPA tonight that came in at 1.071 instead of 1.077. Not a big deal, but I still feel like I'm wasting and doing something wrong.

Currently, I remove the bag, hold it above the kettle for a bit, then move it to a bucket. Then pour a half gallon of water or so over the bag (while in the bucket), wait a bit, lift the bag, let it drip and then pour the contents of the bucket into the kettle. I do this about 3-4 more times.

But I know I'm still wasting a lot of precious wort because it doesn't run clear when I'm done with my process, I just run out of time/ space/ patience and move on. What do others do? How can I be more efficient

EDIT: since I'm sure people will ask, there was only 8 oz. of unfermentables in the recipe (Crystal) and I mashed at 154.
 
I would place the grain bag in the bucket, add your water and STIR THE CRAP OUT OF IT. Just like your dough in, you want to exposure the grains to the maximize amount of surface area of water and let the gravity come to a second stable gravity.

Do you have any gravity readings and volume notes from your first runnings and second runnings? Also recipe and pre boil gravity and volume if you have it.

@Doug293cz thought you might be interested.
 
Skip the sparge entirely if your pot allows it.

I don't sparge at all and formulate recipes at ~80% brewhouse efficiency for ~10lb grain bills.

There is a lot to be said for full-volume no sparge mashing and a squeeze of the bag. I don't muck about. Squeeze like you mean it. 2-3 minutes of effort for repeatability and consistency.

0.045 gallons/pound of wort lost to absorption.

Added bonus, grain bag doesn't drip much if at all. Neatness is very important to other members of my household.
 
I would place the grain bag in the bucket, add your water and STIR THE CRAP OUT OF IT. Just like your dough in, you want to exposure the grains to the maximize amount of surface area of water and let the gravity come to a second stable gravity.

Do you have any gravity readings and volume notes from your first runnings and second runnings? Also recipe and pre boil gravity and volume if you have it.

@Doug293cz thought you might be interested.


Good idea, but I would need a bigger bucket to stir it all. I forgot, I do squeeze the crap out of the bag as part of my process too. I do not do any pre boil readings. Strike water is 5 gallons, sparge with about 2.5 gallons, end up with 5 gallons. Recipe is 10 lbs pale malt, 2 lbs honey malt, 8 oz C80, 8 oz flaked barley.
 
Good idea, but I would need a bigger bucket to stir it all. I forgot, I do squeeze the crap out of the bag as part of my process too. I do not do any pre boil readings. Strike water is 5 gallons, sparge with about 2.5 gallons, end up with 5 gallons. Recipe is 10 lbs pale malt, 2 lbs honey malt, 8 oz C80, 8 oz flaked barley.

Without pre-boil readings of volume (corrected for temperature) and gravity at the correct temperature you're working blind.

If targeting improved efficiency is something you care about (not all brewers do), you need to accurately know

pre-boil volume and gravity. This data can highlight a myriad of areas for improvement.

See the thread in my sig below for more info on efficiency. May be useful?
 
There's not enough information to determine where your efficiency might be lacking, although one simulation I did had your max possible OG at 1.073. To get a predicted 1.077 OG, I had to set the grain absorption in the model to 0.045 gal/lb (Gavin's number) which requires very aggressive squeezing. How did you determine your target OG (what parameters did you feed your calculator)? My simulations assumed 100% starch to sugar conversion efficiency, so you must be close to that (or your OG would be even lower.)

One thing you could do to improve efficiency is squeeze aggressively before sparging, and after each sparge step. The less sugar left in the grain after each step, the higher your efficiency will be.

With a pseudo fly sparge like yours, the only way to be able to figure out where in your process the efficiency losses are is to have a first runnings SG measurement to go with the grain bill and strike water volume. That information can be used to calculate your conversion efficiency directly. If conversion efficiency is low (less than 95%) than an incomplete mash is part of your problem, and finer crush and/or longer mash can help with that. If your conversion is good, then the issue has to be with lautering. Here is where better squeezing or more effective sparging can help.

Brew on :mug:
 
There's not enough information to determine where your efficiency might be lacking, although one simulation I did had your max possible OG at 1.073. To get a predicted 1.077 OG, I had to set the grain absorption in the model to 0.045 gal/lb (Gavin's number) which requires very aggressive squeezing. How did you determine your target OG (what parameters did you feed your calculator)? My simulations assumed 100% starch to sugar conversion efficiency, so you must be close to that (or your OG would be even lower.)



One thing you could do to improve efficiency is squeeze aggressively before sparging, and after each sparge step. The less sugar left in the grain after each step, the higher your efficiency will be.



With a pseudo fly sparge like yours, the only way to be able to figure out where in your process the efficiency losses are is to have a first runnings SG measurement to go with the grain bill and strike water volume. That information can be used to calculate your conversion efficiency directly. If conversion efficiency is low (less than 95%) than an incomplete mash is part of your problem, and finer crush and/or longer mash can help with that. If your conversion is good, then the issue has to be with lautering. Here is where better squeezing or more effective sparging can help.



Brew on :mug:


I got the 1.077 from beersmith. I gotta be honest though- I'm still learning the program and brewing for that matter, so I will take a look at the program more and see what I can figure. All this talk about absorption and such is above my head at this point.

I mashed for about 40 minutes, as I've read on here that 30 is plenty with a fine crush (and I'm confident that my crush is fine enough for this). Perhaps I will do a full 60 minute mash next time.
 
Getting a final batch size of 5 gallons with an OG of 1.077 with 13 lbs of grain using minimal losses puts your estimated brewhouse efficiency at ~80%. While this brewhouse eff is not at all unheard of, in fact it's a level worth striving for, it's also pretty optimistic when you haven't quite dialed in your process and aren't keeping notes on various stages of your process to determine any areas with shortcomings.

Now, coming up with 1.071 OG with the same parameters equates to an estimated brewhouse eff of 74%, which is very acceptable. If you can consistently hit 74% then I would roll with that and adjust my grainbill to account for it. In the case of your above beer, by simply adding about 1 pound of grain (~$1-2) you will reach your desired OG of 1.077.

Opinion of course without enough precise volume/gravity measurements to work with.
 
As for your sparging technique (0.5 gallon rinse multiple times), it seems like it would be slow and waste effort/time. If you want to do a simple rinse sparge in a bucket then I would just put the entire 2.5 gallons through at once, squeeze the bag, collect those runnings, and move on with the boil (i.e. I would not bother with 1/2 gallon rinse/collect/pour, repeat 4 more times, process). Just rinse the grain as best you can in one fail swoop and move on with life :D. It's possible it could affect your brewhouse efficiency negatively but I would not expect more than a couple percent (0-3%) difference, but may be worth the time/effort savings to be worth it. It's also possible it won't affect your BHEff at all.
 
I got the 1.077 from beersmith. I gotta be honest though- I'm still learning the program and brewing for that matter, so I will take a look at the program more and see what I can figure. All this talk about absorption and such is above my head at this point.

I mashed for about 40 minutes, as I've read on here that 30 is plenty with a fine crush (and I'm confident that my crush is fine enough for this). Perhaps I will do a full 60 minute mash next time.

I'm not a BIAB'er but mash efficiency is something we all think about and deal with. Even if your not concerned with having high efficiency, you still need to know where you are in your set-up/process in order to be able to produce somewhat predicable & controllable gravity numbers.

In BeerSmith, I assume you created and saved your equipment profile to match your set-up as closely as possible? If not that's the first step. Then I would suggest that you adjust your Brewhouse Efficiency until the Target Gravity in Beersmith matches the actual gravity you ended up with after this latest brew. Use that as your baseline.

Now that Beersmith has your profile with your set-up & your process, at least you'll be in the ballpark on your gravity numbers with your current set-up.

Then you can try some of the techniques mentioned by others in this thread and if they produce improved efficiency, you can adjust your Brewhouse efficiency according to the results you achieve.

:mug:
 
Getting a final batch size of 5 gallons with an OG of 1.077 with 13 lbs of grain using minimal losses puts your estimated brewhouse efficiency at ~80%. While this brewhouse eff is not at all unheard of, in fact it's a level worth striving for, it's also pretty optimistic when you haven't quite dialed in your process and aren't keeping notes on various stages of your process to determine any areas with shortcomings.

Now, coming up with 1.071 OG with the same parameters equates to an estimated brewhouse eff of 74%, which is very acceptable. If you can consistently hit 74% then I would roll with that and adjust my grainbill to account for it. In the case of your above beer, by simply adding about 1 pound of grain (~$1-2) you will reach your desired OG of 1.077.

Opinion of course without enough precise volume/gravity measurements to work with.


Thanks for the advice and reassurance. Sounds like my efficiency isn't so bad, just trying to get the most out of what I have. I'll try that sparging technique next too. Thanks again!
 
I'm not a BIAB'er but mash efficiency is something we all think about and deal with. Even if your not concerned with having high efficiency, you still need to know where you are in your set-up/process in order to be able to produce somewhat predicable & controllable gravity numbers.



In BeerSmith, I assume you created and saved your equipment profile to match your set-up as closely as possible? If not that's the first step. Then I would suggest that you adjust your Brewhouse Efficiency until the Target Gravity in Beersmith matches the actual gravity you ended up with after this latest brew. Use that as your baseline.



Now that Beersmith has your profile with your set-up & your process, at least you'll be in the ballpark on your gravity numbers with your current set-up.



Then you can try some of the techniques mentioned by others in this thread and if they produce improved efficiency, you can adjust your Brewhouse efficiency according to the results you achieve.



:mug:


I did set up my equipment profile in beersmith, but that was awhile back and my process has changed a bit, so I will revisit this area and try to figure it ourt. Thanks!
 
I got the 1.077 from beersmith. I gotta be honest though- I'm still learning the program and brewing for that matter, so I will take a look at the program more and see what I can figure. All this talk about absorption and such is above my head at this point.

I mashed for about 40 minutes, as I've read on here that 30 is plenty with a fine crush (and I'm confident that my crush is fine enough for this). Perhaps I will do a full 60 minute mash next time.

Absorption isn't very complicated. Just think about a big sponge in a bucket of water (where the sponge is about 1/2 the size of the bucket.) If you pull the sponge out of the bucket, it will drain a lot of the excess water out of it. If you squeeze it a little, some more water comes out. If you squeeze it harder, even more water comes out. The grain bag (or grain bed in a mash tun) is like a sponge, only instead of water it has absorbed wort. The more grain you have, the bigger the sponge, so the more wort it can hold. In a typical MLT, the grain will hold about 0.12 gal/lb, so 10 lbs of grain would hold 1.2 gal of wort. A moderately drained BIAB bag will hold about 0.10 gal/lb, or 1.0 gal of wort, so we have gained 0.2 gal of extra wort and the sugar it contains. Getting more sugar out of the same amount of grain means higher efficiency. With moderate squeezing, you can get the BIAB absorption down to 0.08 gal/lb, or 0.8 gal for 10 lb of grain. That's 0.4 gal more than the traditional MLT. With really aggressive squeezing (like Gavin) you can get the absorption down to 0.045 gal/lb.

To see the effects of grain absorption on efficiency and OG, I did a full volume BIAB simulation using 10 lbs of grain, assumed 100% conversion efficiency, and 1 hour boil @ 1 gal/hr boil-off rate to yield 5.5 gal post boil. The results are shown below.

Efficiency vs Grain Absorption.png

Brew on :mug:
 
There is no harm in mashing longer - especially as you are getting a feel for your own process and your own system. Some biab folks mash 90 minutes which tends to replicate a 3 vessel system with 60 minute mash and 30 minutes of sparging.
 
On the squeezing it's not that tricky to get the absorption down. Again the main reason is not to eke a point or too of efficiency but to target consistency. If I'm squeezing to this level each time there is almost no chance of over-squeezing from brew to brew. I know exactly where I'll be each time.

My process (2-3 minutes of work)

  • Don some latex gloves to minimize mess.
  • Lift the bag sequentially and let most of it drain as you go. makes lifting easier than all in one. (I have no facility for a hoist or pulley)
  • Set it on colander over pot.
  • And then twist it. (Just like you do when taking the garbage out. Twist the bags to reduced the volume some)
  • I just keep squeezing till I'm at the target preboil volume.

    Squeezed bag ~0.045 gallons/pound of grain (9lb grain-bill)
    Squeezed Bag.jpg
  • Collander and grains are placed on a plate to cool and then into the flower beds later on.

    Discarding Grains.jpg
  • Toss gloves, onto the heating/skimming/boil etc..
 
Wow, thanks to everyone who replied. A graph even! I'll be looking to implement many of these tips and tools on the next batch.
 
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