First time BIAB - 4 gal pot... Lost

[Javaslinger]

Ok, this is BOTH my first All Grain attempt and BIAB. I'm choosing BIAB as it's a bit easier and I think I can still do it even with my puny pot...

Ok, beginner so be gentle. I'd like to do an Chocolate Milk Stout via BIAB and I have a 4gal brewpot. I'm imagining I could pull off maybe a 2gal batch?

I really struggle with scaling recipes and now with BIAB it's just that much more confusing. Can someone walk me through this?

Thanks!

 

[tmendick]

This is a good start Priceless Calculator
Is this your first All Grain?

 

[Javaslinger]

It is indeed my first all grain....

 

[LLBeanJ]

First thing to do is find yourself a recipe. Do you have one? If so, please post it, even if you haven't scaled it down for 2 gallons yet.

 

[Javaslinger]

The options are bewildering... mostly I'm curious about how to scale it so that it will fit in my pot. I'm not even sure that a 2gal batch will work in 4 gal pot during the BIAB bit...

But for the purposes of the exercise... How about this one?

https://www.brewtoad.com/recipes/doug-rhoades-milk-stout-modified

Now I'd be happy for a suggestion for another recipes if you know of one.

 

[JohnSand]

You can easily brew 2 gallons in a four gallon pot. You can brew 4 or even 5.
If you have been doing partial boils with extract, you can do the same with grain, topping off after the boil. I brewed with a five gallon pot for a long time, making 5 gallon BIAB batches. Mash in your pot of course, it can go in a warm oven to hold temperature. When you pull the grain bag, put it in another pot and dunk sparge. Leave a gallon of headspace, watch carefully as you come to a boil. Turn down the heat to keep from boiling over, stirring and spraying it with cool water help too. After the hot break you can add more wort, leaving only a half gallon of space. As the wort boils down, add more wort. Top off in the pot and the fermenter as necessary.
Looking at your recipe, it's a big beer. But a two gallon batch of it will only have about 6# of grain, which you can fit in your pot with enough water to mash. After that just drain the bag and top off, even if you boil down to less than two gallons.

 

[LLBeanJ]

Scaling is pretty straightforward. The ingredients have a linear relationship when it comes to batch size, so if you want to brew a half recipe, you just cut all the ingredients in half. The recipe you linked is a 5 gallon recipe and you want to brew it as a 2 gal batch, so you would multiply all the ingredients by 2/5 or .4. Once you have your ingredient amounts determined, you can use a calculator like BeerSmith or the Priceless Calculator linked above in tmendick's post to determine water volumes and available mash tun volume to see if all the grains and water will fit in your kettle. As John stated above, even if they don't fit for a full-volume mash, you can use a sparge to work around it, however a 2 gal brew of the recipe you linked should fit your BK without requiring a sparge.

 

[NSMikeD]

Scaling is pretty straightforward. The ingredients have a linear relationship when it comes to batch size, so if you want to brew a half recipe, you just cut all the ingredients in half. The recipe you linked is a 5 gallon recipe and you want to brew it as a 2 gal batch, so you would multiply all the ingredients by 2/5 or .4. Once you have your ingredient amounts determined, you can use a calculator like BeerSmith or the Priceless Calculator linked above in tmendick's post to determine water volumes and available mash tun volume to see if all the grains and water will fit in your kettle. As John stated above, even if they don't fit for a full-volume mash, you can use a sparge to work around it, however a 2 gal brew of the recipe you linked should fit your BK without requiring a sparge.

^ This

This it what I do. I originally used BIABacus (free excel) and then switched over to BreerSmith

Filling a pot to the rim is not going to make for a fun brew day. Holding back water is very easy. The software will do the calculation for you and you'll find topping of the kettle for the boil is a lot more rewarding than spilling beer from a pot filled to the rim, or only getting 1.5 gallons of beer because you have two inches of trub at the bottom of your primary.

Tip:
I have a dowel and a tape measure I use to measure the water depth so I can calculate volume quickly. I use a spread sheet with my pot dimensions radius and height and use V=∏•r^2•h

Another Tip:
With small batches, I find trub loss to be very annoying - so I target my water volumes to leave as much trub in the boil kettle as possible (about a half gallon). I use aquarium mesh bags for my hop additions and Irish moss. After cooling, I let the wort rest for 20 minutes so everything settles before transferring to the primary.

 

[C-Rider]

When I started BIAB back in 2011 I was doing 2 gallon batches in a 4 gallon pot. So yes you can but you have to watch out for boil overs when you first reach 212*.
That said I've since moved up to a 5 gallon pot and am still doing 2 gallon batches. Each gives me approx 16 bottles. This video was made at the end of 2011 and I've made some changes in the past 6 years but basicly this is what I do. On thing nice about 2 gallon batches is can have a lot of different beers in your pipeline. 5 gallons gives you what 52 bottles of the same thing?