BAIB Partial Boil

[dalereed]

Hey all. I have a few BIAB brews under my belt over the last year and have come up with a couple of recipes that I'd like to MAKE MORE of. I've done some searching but, haven't found any comments on exactly what I'm looking for. I have 2 fermenters and would like to make 10 gallons worth of wort in my 10 gallon pot. I did a couple of extract brews with a friend that got me into this and think that I should be able to use the full grain bill for a 10 gal batch to end up with a 5 gal boil then, split it between the 2 fermenters.

Does that make sense? Basically, a partial boil 10 gal batch.

Thanks for your input.

Dale

 

[wildactbrewer]

I don't see why that wouldn't work. I do partial BIAB as well just on a 5 gallon scale.

The strike water volume gets a little trickier but after a few batches I think I've nailed it. The big thing you have to watch out for is hop utilization. There are people out there WAY smarter than me that can help with that

 

[MarshmallowBlue]

Another thing to look for is lowered efficiency with heavy grain bills.

 

[wilserbrewer]

With all grain. Your goal should be to top up with water as little as possible. So I would shoot for a 9 gallon boil, boiled down to 8 and topped off for a 10 gallon batch.

Trying to only collect and boil for 5 would be rather inefficient.

 

[dalereed]

Thanks!

 

[Psylocide]

Don't want to hijack this thread but it's here and I had a similar question:

If I wanted to do a 5 gal BIAB batch in my 7.5 gal kettle, could I up the grain bill and make a stronger OG wort, knowing I'm going to top off and dilute it a bit?

I don't see how this would be much different from doing a partial boil extract batch. But getting the numbers right could be tricky.

 

[bobbrews]

I would do a full wort boil with no top off water for the best quality. Do an 8 gallon boil and rack something like two 3.5 batches in two primaries. You can totally change up the dryhop to see what combos you enjoy better for essentially the same beer.

As long as you're not implementing a secondary, a bit of headspace in the primary fermenter is actually a good thing; easier to aerate and easier to handle. After primary fermentation, you will have a dense layer of C02 protecting the beer. It also allows more room for leaf dryhops, if doing.

 

[RM-MN]

Don't want to hijack this thread but it's here and I had a similar question:

If I wanted to do a 5 gal BIAB batch in my 7.5 gal kettle, could I up the grain bill and make a stronger OG wort, knowing I'm going to top off and dilute it a bit?

I don't see how this would be much different from doing a partial boil extract batch. But getting the numbers right could be tricky.

Instead of topping off, something I've tried the past couple batches is to make the amount of wort I can without running my pot over with the idea of sparging to volume. When the mash is done, I set the bag of grain in a colander that is sitting in a bowl and start heating the collected wort which is less than what I need for my batch. When the wort reaches boil and the hot break subsides, I sparge the grain in the bag and add that to the pot where I again get hot break but a much smaller amount so it doesn't boil over. I've used boiling water for the sparge so it doesn't stop the boil for long when I add that wort to the pot. Since hot break is when the pot is likely to boil over, I avoid that and can sparge to a greater volume. This keeps my efficiency up better than adding top off water.

 

[Psylocide]

Instead of topping off, something I've tried the past couple batches is to make the amount of wort I can without running my pot over with the idea of sparging to volume. When the mash is done, I set the bag of grain in a colander that is sitting in a bowl and start heating the collected wort which is less than what I need for my batch. When the wort reaches boil and the hot break subsides, I sparge the grain in the bag and add that to the pot where I again get hot break but a much smaller amount so it doesn't boil over. I've used boiling water for the sparge so it doesn't stop the boil for long when I add that wort to the pot. Since hot break is when the pot is likely to boil over, I avoid that and can sparge to a greater volume. This keeps my efficiency up better than adding top off water.

Ahhh... so sparge to boil volume while keeping the same grain bill? Do you find that you're hitting your numbers doing this?

I could easily do this if I'm understanding you correctly.

 

[RM-MN]

Since you are collecting the sugars by sparging it gets you the same efficiency or just a bit higher than if you were doing a full volume mash.

 

[Psylocide]

Since you are collecting the sugars by sparging it gets you the same efficiency or just a bit higher than if you were doing a full volume mash.

Sold.

I'm going for it, thanks.

 

[dalereed]

So, I see lots of mentions of not topping off - except for extract partial boils but, no real reason given besides quality, better results, etc. Is there some chemistry involved that makes a difference? By using the same water supply and pre-boiling it for sanitation, this non-chemist wouldn't think it would change things much. If the concentrated wort is where it supposed to be numbers-wise, there must be something else that changes it?

 

[bobbrews]

So, I see lots of mentions of not topping off - except for extract partial boils but, no real reason given besides quality, better results, etc. Is there some chemistry involved that makes a difference? By using the same water supply and pre-boiling it for sanitation, this non-chemist wouldn't think it would change things much. If the concentrated wort is where it supposed to be numbers-wise, there must be something else that changes it?

Hop utilization gets cut in half and a large part of your beer loses the benefits offered by the boil. Boiling isn't just for sanitizing.

Boiling wort is normally required for the following reasons:

1. Extracts, isomerizes and dissolves the hop α-acids.
2. Stops enzymatic activity.
3. Kills bacteria, fungi, and wild yeast.
4. Coagulates undesired proteins and polyphenols in the hot break.
5. Evaporates undesirable harsh hop oils, sulfur compounds, ketones, and esters.
6. Promotes the formation of melanoidins and caramelizes some of the wort sugars (although this is not desirable in all styles).
7. Evaporates water vapor, condensing the wort to the proper volume and gravity (this is not a primary reason, it's a side effect of the process).

 

[Magnus314]

If the concentrated wort is where it supposed to be numbers-wise, there must be something else that changes it?

i think you'd be fine IF the OG is where it needs to be pre-dilution and you adjust the hops.

But it will be very inefficient to get that wort if the OG is moderate or higher unless you use enough rinse water (higher volume or sparge) to get more out of the grains.

If you DO get your Pre-dilution OG you're doing fine. If not, sparge some and dilute less.

 

[dalereed]

Thanks Magnus. That sounds like the plan. I'll be doing one of these over the next month or so and will report back.