Modified BIAB

I am slowing making the move to all grain after several year of extract and partial mash brewing and I have been doing a modified version of Brew in a Bag. I don't have a mash tun built just yet so in the interim I am using an unmodified cooler to mash in and using two 5 gallon paint strainer bags. I did a Hef this past weekend and wished my gravity was a little higher.

Here's what I did...

5 lbs Wheat malt
4 lbs Pilsner malt
1 oz Hallertau (60 min)

Mash at 153 for an hour with 12 quarts of water.
Sparged with additional 12 quarts of water at 170 for 15 minutes
Boil = 60 min

OG I got was 1.040. At the very low end of the range.
I did double crush the grains because I read that it helps increase the efficiency of BIAB.

What can I do to increase my gravity?

I am in a very similar situation. Mashing in an un-modified cooler with a large bag. Terrible efficiency.

I'll be interested to hear what the cheapest & easiest ways are for us to increase efficiency.

I'm in a somewhat similar situation.

Assuming my calculations are correct, my first BiaB (Mash in a Bag) topped out at just over 88%... and they have been spiraling downhill since then..

if you are holding temps, then check your crush. i just mash in the BK. if you can reduce headspace you can hold your temps for an hour or more. then make up the rest with your sparge water.

88% aint bad.

Yup... 88% is darn good, which is why I'm a bit put off that my last batched have been in the 60's...

Brewing again tomorrow... gonna REALLY take my time on them and hope for another improvement.

I find when I double crush I get lots of dough balls. if you dont break them up you'll lose a good chunk of efficiency.

how are you sparging?

are you stirring enough when you dough in?

i made my last mash too thick .. i know that cost me some points .. i have been doing much beter with thinner mashes ..

Fathand said:

I am slowing making the move to all grain after several year of extract and partial mash brewing and I have been doing a modified version of Brew in a Bag. I don't have a mash tun built just yet so in the interim I am using an unmodified cooler to mash in and using two 5 gallon paint strainer bags. I did a Hef this past weekend and wished my gravity was a little higher.

Here's what I did...

5 lbs Wheat malt
4 lbs Pilsner malt
1 oz Hallertau (60 min)

Mash at 153 for an hour with 12 quarts of water.
Sparged with additional 12 quarts of water at 170 for 15 minutes
Boil = 60 min

OG I got was 1.040. At the very low end of the range.
I did double crush the grains because I read that it helps increase the efficiency of BIAB.

What can I do to increase my gravity?

Click to expand...

It's been asked but I'll second it. How did you sparge?

The way I'd do it is heat that sparge water up in your boil kettle to about 185F, pull the bag out of the MLT (let it drip drain first), then dunk it into the boil kettle/stir and let it drip before discarding.

Thinner mash, stirring really well, crush, squeezing the bag, raising the temp for mash out...

All of the above will help with your BIAB mashes.

"Thinner mash, stirring really well, crush, squeezing the bag, raising the temp for mash out... "

Did all those but perhaps didn't stir it well enough when we sparged. What we did was add the 12 quarts of water at 180 degrees and then moved the bags around until we got close to 170 then closed the cooler and let it go.

Perhaps next time I'll remove the bags of grain and dunk them as suggested. Really agitate them.

If my calculations are correct the efficiency was like 60%. That sucks.

For higher gravity, you might just consider up-ing the amount of grain you are using in the recipe.

What wyzazz said also works. You can increase the crush on your grain and that will help quite a bit. Of course doing a good sparge and boiling off any excess volume helps also.

Quick fix? Spike it up with a little extract

so you split the grains into two bags, tie them up and drop into the cooler? is that for sparge or sach rest?

are they fully submerged? do you actually stir the grain at dough-in?

so you split the grains into two bags, tie them up and drop into the cooler? is that for sparge or sach rest?

are they fully submerged? do you actually stir the grain at dough-in?

Click to expand...

Yup 2 bags tied loosely. They are fully submerged and we stir the crap out of it at dough in.

We really didn't stir it that much for the sparge so I guess the next time we will try and remove the grain bags and dunk them/stir them. Perhaps a thinner mash will help too.

I just want to be able to use an all grain recipe and not have to modify it with extra grain or extract even. But I understand that everyone's system is different and that it is going to take some time for me and my brewing buddies to dial ours in.

I just did two batches using a set-up just like yours. I have the 15gal Xtreme cooler unmodified and two 24"x24" bags. One recipe was OG 1.052 and the other 1.072, and I was able to hit both (overshot the first by 6 pts). I was able to get 70-75% effic. on both recipes, and I think the most important components were this: 1.) use tons of water. I boiled down to 5gallons for each, but started with a boil volume of ~8-9gals each (took an extra hour and half of boiling in two diff pots to do this). It takes a lot longer, and you run the risk of some carmelization (supposedly), but the extra water in your sparge and mash can really help. 2.) for the one where I overshot the OG by a few pts I did a mashout in my brew kettle, which im guessing helped to boost the extraction. 3.) during batch sparge stir the hell out if it and leave it for 5-10mins. 4.) if your arms get tired from holding the bags while they drain, just dump the bag into a bucket with a spigot and allow it to settle out liquid in there, then drain from bucket into the brew pot (no point wasting tasty sugars).

BIAB effic requires work, but it makes AG on the stove possible =)

do you know exactly how much wort you had pre-boil (what was the pre-boil gravity) what was the exact post boil volume and gravity? what temp did you take the gravity reading at? what temp is your hydrometer calibrated at? how fine was your crush?

the reason I ask about volumes is.. at 5.50 gallons your recipe would give 1.044 at 70% efficiency.. at 5 gallons it gives 1.048.. if you ended up with 5.75 gallons... that gets you around 1.042.. not saying it's the exact cause of your low reading but it's a possible factor contributing to it.

Mystic echoed what I was going to post, plus based on my experience 4 lbs of crushed grain is about the most you want to put in a 5 gallon paint strainer bag. If the bag is too tight you will get dough balls that you don't even see and lose a ton of efficiency. And try the dunk sparging and really push the the bag around a lot with a spoon to loosen up the grains at mash in, mash out, draining and dunk sparging. This will increase your efficiency a lot.

Dang I never even thought about trying this out. I would probably have to do a split boil because i have a 3 gallon and 4 gallon boil kettle. Not to high jack the thread but if you do a spilt boil what would you do with the hops? only put them in 1 kettle or split between the two?

split the hops evenly... at least that's what I would do.

I often collect more wort volume than my brew kettle can handle. So instead of calculating hop utilization etc. I often just boil the volume down to what my 30qt pot can handle, and then start the 60-90min boil with hop additions.