Does this setup seem doable?

[howamidriving]

After a couple years extract brewing with a few small partial mashes I'm looking into moving into all-grain BIAB. So here's what I'm thinking:

For most brews I'll shoot for 2.5-3 gallon batches. Mostly lower ABV stuff, so like OG around 1.05 or so. I'd like to get a 5 gallon brew kettle and brew on the stove top.

I plugged some numbers into brewersfriend and at 60% efficiency 7lbs of grain gets me to 1.052 for a 3 gallons. 1.25qt/lb mash gives 8.75qt mash. I'm think that leaves me some room to do a pour over sparge up to roughly boil volume.

I guess my questions are: Can I expect 60% efficiency out of this setup? With the volume added by the grain is this still going to fit in a 5 gallon pot? And does this idea seem ok in general?

Any input is greatly appreciated, thanks!

 

[physics911]

Are you asking if you can get 60% from BIAB, or if the 5 gallon kettle matters?

BIAB can easily get over 80% efficiency.
I haven't used a 5g pot, so I can't be sure it will fit for a full volume mash, but I'm relatively certain it will. I do 5g batches, with 12lbs of grain, in an 8g pot and have some room to spare.

To start with, I wouldn't really even worry about sparging. Just do a full volume mash and drain your bag when you lift it out.

 

[howamidriving]

I guess I was asking more if you can get 60% out of BIAB. Just to clarify, when you say full volume mash do you mean just filling the kettle up and not worrying about mash thickness at all

 

[physics911]

That's correct.
Use one of the many calculators available to determine how much water you need for your boil + grain absorbtion, and put that in the pot and heat to your strike temperature. However, if that is too much for your pot (e.g. the calculator tells you to use 4.5 gallons, which would surely spill over when you added the grain), just add as much water to the pot as you can, minus what you figure will be displaced when you add the grain. Then when the mash is done, you can bring the water level up to the full boil volume.

Make yourself a dipstick to measure how much water/wort is in your pot at a given time. You can do this with a long spoon, siphon rod, etc. Just put a gallon of water in the pot and mark the stick, then another gallon and mark, and so on.

 

[doug293cz]

Check out the calculator here: http://pricelessbrewing.github.io/BiabCalc/.

With a 7 lb grain bill, you can easily achieve 85% or better mash efficiency for a 3 gal batch, IF you get close to 100% conversion efficiency. To get near 100% conversion, you will most likely need a finer grain crush than provided by most HBS's. Crush is very often the limiting factor in mash efficiency (which is equal to conversion efficiency times lauter efficiency.)

There is no reason to limit your mash thickness to 1.25 qt/lb. That rule of thumb comes from fly sparge systems, and is inappropriate for batch sparge or no-sparge. Kai Troester has shown that thinner mashes (up to about 2.5 qt/lb at least) tend to provide better conversion efficiency, so you are better off mashing thinner.

Your kettle is too small to do a full volume mash (i.e. no-sparge) with 7 lb of grain, so you will need to do either a batch sparge in a separate vessel, or do a pour over sparge. If doing a batch (dunk) sparge, you want to adjust your first and second runnings volume to be about equal (run off ratio near 1) using the linked calculator. This will maximize your efficiency. If doing a pour over sparge, you want to use at least 1 gal of sparge water.

Brew on

 

[howamidriving]

Cool that's some great info! Thanks for the info guys

 

[dstockwell]

I plugged some numbers into brewersfriend and at 60% efficiency 7lbs of grain gets me to 1.052 for a 3 gallons. 1.25qt/lb mash gives 8.75qt mash. I'm think that leaves me some room to do a pour over sparge up to roughly boil volume.

I guess my questions are: Can I expect 60% efficiency out of this setup? With the volume added by the grain is this still going to fit in a 5 gallon pot? And does this idea seem ok in general?

Any input is greatly appreciated, thanks!

Brewersfriend works off Brew House efficiency which will always be lower than mash efficiency. Now depending on your crush you should do better than 60%. I do 3 - 3.25 batches starting with 5g of water. Using BF I use 65% efficiency, and usually fine with that based on my system.

 

[Aristotelian]

I do 2.5 G batches on stovetop, BIAB. I have not done anything special and I have gotten 63-65% every time. Never less than 60%.

 

[theseeker4]

I guess I was asking more if you can get 60% out of BIAB. Just to clarify, when you say full volume mash do you mean just filling the kettle up and not worrying about mash thickness at all

You can definitely get high efficiency out of BIAB. The maximize the sugars you get out of the grain, squeeze the grain bag as hard as you can until you can't get any more liquid out of it. If you are sparging, the best way to get the most sugars out is to squeeze as much as you can, then place the grain and bag in a second container containing your sparge water, and mixing the grain up until all the clumps are broken and the grain is freely flowing in the water. Then pull the bag, and squeeze it again, as hard as you can, to get all the sparge liquid out. Doing this, my most recent batch had an efficiency over 80%.

 

[NathPowe]

OP - it sounds like your question is geared a bit more toward efficiency, but in the event you are researching kettle size with regard to a potential purchase I'd recommend going bigger. For 3gal of finished beer using the BIAB method I would want a 10gal kettle. This gives you plenty of room for big beers and longer boils, and the flexibility to bust out 5-6gal batches if the mood strikes you.

Just my two cents. Cheers and enjoy the brew.

 

[RM-MN]

I guess I was asking more if you can get 60% out of BIAB. Just to clarify, when you say full volume mash do you mean just filling the kettle up and not worrying about mash thickness at all

I don't know if I can get 60% efficiency with BIAB. I've never got under 80%.

Mash thickness doesn't matter too much except if you make it too thick you can't stir very well. Thinner mashes will convert faster and with a little higher efficiency.

Without sparging and a 5 gallon pot you will be limited to about 2 1/2 gallons of beer. If you use a sparge step, you can raise this to about 3 gallons because your limiting factor is the amount of grains plus water that will fit into your 5 gallon pot.

If you expect to get 3 gallons of beer from using a 5 gallon pot you will have to be very careful with the boil so you don't boil off too much water or you will have to add water back before you dump it into the fermenter.

 

[howamidriving]

Thanks again everyone for all the input. If I have time tomorrow between bottling some stuff and work I'll stop into the hbs and price some stuff.

I don't know if I want to spend extra on a bigger kettle and I'm also a little concerned how long it will take me to bring that much water to a boil on my stove top

 

[Aristotelian]

Without sparging and a 5 gallon pot you will be limited to about 2 1/2 gallons of beer. If you use a sparge step, you can raise this to about 3 gallons because your limiting factor is the amount of grains plus water that will fit into your 5 gallon pot.

If you expect to get 3 gallons of beer from using a 5 gallon pot you will have to be very careful with the boil so you don't boil off too much water or you will have to add water back before you dump it into the fermenter.

You can always top off after you have removed your grains to cheat a little bit. My kettle is 4 gallons and I end up with 2.5 gallons easily. I think you could get 3.5 without too much trouble.