Batch Volume Question

[jeffdill]

So it was a little more straightforward for extract, since I would just top it off with water to get to where I want...

What volume do you normally formulate your recipes to? I've seen 5 gallons, 5.5 gallons, 6 gallons...I want to bottle as close to 5 gallons as I can. Do people formulate for higher volumes to offset loss due to hops or something?

Also, approximately how much water do you boil off during 1 hour with a turkey fryer? I just bought the "Bayou Classic SP10 High-Pressure Outdoor Gas Cooker"

Looking forward to building my mash tun tonight and my first all-grain batch this weekend!

 

[rockytoptim]

I usually target 5.5 gallons into the fermenter so after hydro readings and trub I get 5 gallons into the keg.

 

[Homercidal]

Well, for starters, what you want to know is pretty much the difference between extract and AG.

You can build a recipe by deciding how big your batch is going to be. Let's choose 5 gallons as an example.

From there you know you are going to need AT LEAST 5 gallons of water, right? BUt you will lose a certain amount in the grains, because they soak up the water like a sponge! So find out how much grain you will use and add the amount of water they will take up to the 5 gallons. Let's figure .2 gallons per pound of grain, so 8 lbs of grain will require 1.6 gallons of water extra.

So you're up to 6.6 gallons. Now find out how much water you will lose to boiling. Boil-off rate is different for different systems, BTUs, and Conditions that day. Let's assume a rate of 1.3 gallons per hour. So you add the 1.3 to the 6.6 and you get 7.9 gallons total so far.

You can also add in deadspace in the mash tun, which you don't know because you haven't built and tested your yet, but you can guess maybe .25 gallons (I think it's better to have more water than less, personally.)

And also there is how much loss in the bottom of the boil kettle to break material an hops, so figure .25 gallons for safety.

So you are now up to 8.5 roughly, which is maybe a little more than you will actually need, but I prefer to start with extra water and maybe end up with a bit more beer at the end. Some of these things you won't be able to judge until after you've brewed a batch or two, because they are dependent on your particular system.

You can try Beersmith and have it do calculations for you, but IMO it's at least as hard to get BS to do it right, especially before you know your equipment's particulars, as it is to do the math by hand.

 

[Salamander]

Will this formula work for a BIAB batch? I never get my strike water spot on.

 

[Homercidal]

BIAB is essentially the same as batch sparging. The only difference is you are removing the grains from the water, not removing the water from the grains.

Just keep in mind that there is a wide range of possible formulas as far as grain to water ratio and number of sparges. Just remember to add water to account for grain absorption, deadspace in the mash tun, boil-off in the BK, and deadspace in the BK, and then finally deadspace and hops absorption in the fermenter.

You can split the sparge into 2 by sparging twice and using half of the total sparge water in each pass. Or you can do a single sparge and use all of the sparge water in a single pass. I personally have switched to doing single sparge because it's faster and easier, and if there is an efficiency difference, it's not enough to offset the time savings IMO. I just add a bit more grain.

The amount of water and grain used will vary depending on your personal efficiency. Some people might post an 80% efficiency with their recipe. If you are only getting 70%, then you must adjust the recipe by adding a bit more grain.

You can figure your efficiency by taking careful measurement of your brewing water and grain. Plug it into an efficiency formula and determine how efficient you are at getting the sugar from the grain into the Boil Kettle. You need to measure precisely to get an accurate number. After you have your wort in the BK you can take a gravity reading and adjust it higher by adding extract, or lower by adding water.

I'll also state my personal opinion here by saying that you should not concern yourself with hitting a particular efficiency to start out with. After you've had a few batches under your belt you might feel obliged to tweak your crush, method, or equipment to improve your efficiency. It won't really affect your beer quality, it will just cost a small amount more in grain. Some brewers even try to keep their efficiency down a bit because they feel extracting too much of the sugar from the grain is also extracting more of the husk flavors.

If I were getting less than 70% I would definitely look into improving that. It's my personal opinion that 70% should not be hard for anyone to reach with a good crush and a decent sparge. And it's certainly not anywhere near the supposed point at which you get tannins or whathaveyou from the grain husk.

 

[jeffdill]

So should I be shooting for 5.5 gallons in the fermenter, and approx. 6.5-7 gallons to the kettle for the boil?

 

[Homercidal]

I would shoot for 5.5 in the fermenter if you can handle a small amount extra. The amount you put into the kettle will be determined by how long you boil, mostly, but also by the amount of hops you use and what type. Hops in the BK will absorb some wort just like grain (but to a small extent).

I think most people plan on losing about a gallon during a 60 minute boil, so if you plan on a 60 minute boil then 6.5-7 is a good number in my opinion.

In the end, what matters most in my opinion is the gravity. You should be shooting for what the recipe calls for. If you have a little less beer, or a little more beer, in the end, that's no big deal. If you take a gravity reading before boiling you can adjust the gravity or the volume with extract, extended boiling time, or water by using an online gravity calculator to project what the gravity and volume will be by the end of the boil.

If your gravity is low, you can either add extract to bring it up, or boil more water out by boiling for like 1/2 hour extra before adding the 60 minutes hops, or something like that. The actual time to extend the boil would be determined by how far off the gravity is.

It's really a numbers game. You will get a feel for it and will be able to get a very good idea of what you need to do as you brew a few batches. If you take good notes and measurements, that is.