Noob BIAB question?

[dkilday2]

Hello! I am trying my second brew and first BIAB tomorrow. I have run everything on a calculator and need around 4.5 gallons of water. I only have a 5 gallon stockpot so I am afraid I will overflow if I do a full volume mash. My question is can I mash with say 3 gallons and top of with the rest of the water to what my preboil volume would be? Also If I dont do this could I reserve some of the water and do a dunk type sparge then add it in to the kettle? Any feedback is Appreciated. Thank You!

 

[NothingRhymesWithCurtiss]

Using a 5 gallon pot for a 5 gallon BIAB batch, you're most definitely going to overflow your kettle.

Seeing as how you're going to lose some wort due to boil off, you're going to need to top off, regardless of if you dunk sparge or not.

My opinion is that you should try and get your pre-boil volume to around 4.5 gallons (and keep an eye on the kettle to ward off boil-overs) to maximize hop utilization, and top off with water once you've cooled the wort to close to pitching temps.

Hopefully this helps.

 

[dkilday2]

Sorry my original post wasn't super clear. I'm actually only trying to get 2.75 gallons of finished beer. Figured that way with tub loss in the fermenter I will still have at least 2.5 gallons of finished beer. The calculator I ran said I will need around 4.8 gallons of water total and my question was is their harm in just mashing with around 3 gallons and then adding water to around 4.5 to take into consideration boil off and trubb loss? Will this dilute my original gravity of I don't use the extra water to soarhe first.

 

[Aristotelian]

I think you will be fine. I do 2.5 gallon batches in a 3 gallon pot. I mash with about 1.75 G, then sparge with another .5 G. Then I top off to 2.5 G, and then continue to top off to keep it at 2.5 G throughout the boil. Works for me.

 

[pricelessbrewing]

What calculator are you using?

My plan would be to choose your Mash thickness/sparge volume so that your Mash volume is no more than 4.5 gallons. Use the remaining water as a dunk sparge. Mash, pull bag, squeeze, dunk sparge, stir for five minutes, pull bag, and squeeze again.

 

[Chris_Primavera]

Without knowing more about your recipe it will be difficult to provide exact numbers.

For 2.75 gallons of "finished beer" (your volume into packaging) you will need about 3.1gallons or 12L in your fermentor.

A 1.055 OG would require a bit less than 7# of grain

Assuming a 60 minute boil, you would need approximately 5.2 gallons of water and your mash volume would be 6 gallons.

You could hold back one gallon from the mash and add it prior to boiling. Your efficiency will take a hit and you will have difficulty with boilovers.

If a bigger pot is not an option, you can split the batch into two pots or go for a slightly smaller batch.
Topping off after your wort has chilled is bad juju as you are not sterilizing the addition.

 

[dkilday2]

Thanks guys that is actually very helpful advice. I believe I will mash with a smaller volume and sparge. I reduced the recipe a bit as to get 2.75 gallons of beer into fermenter leaving me close to 2.5 with trubb loss. 4.45 lbs of grain and I wasnt sure what my book off rate was just having Brewed once so I went with 1.25 per hour and a grain absorption of 0.08. Kettle trub loss of 0.25. Using those numbers I come up with 4.6 gallons of water needed . The recipe I'm using is the half recipe of the centennial blonde so technically my recipe is for 2.75 gallons. I believe in his recipe he did it for 5.5 gallons to account for a half gallon of trub so he would still have 5 gallons of finished beer. This way I should have 2.5 gallons finished beer.

 

[TexasWine]

Might I suggest an attempt to reduce your boil off? If you're boiling off 1.25 gallons, that's over 25% of your starting volume, assuming it's 4 gallons. This will result in a significant concentration of the minerals that are in your water. Personally I try to keep my boil off at around 10% or less of my starting volume.

 

[pricelessbrewing]

Might I suggest an attempt to reduce your boil off? If you're boiling off 1.25 gallons, that's over 25% of your starting volume, assuming it's 4 gallons. This will result in a significant concentration of the minerals that are in your water. Personally I try to keep my boil off at around 10% or less of my starting volume.

My small batches boil off is .5 gallons. Sometimes I brew .75G. That's 40% of preboil volume. There's significant darkening during the boil as a result, but it works really well for high abv beers and bier de gardes as I get more caramelization/malliards/whateveryouwanttocallthem per hour than normally

 

[dkilday2]

Thanks for the feedback guys. To be honest I'm not sure what my boil off is. I've only done 1 brew and didn't take any notes which was pretty dumb on my part. It was an extract kit and I just topped off in the fermentor. I used 1.25 gallons per hr because that was the default value in the simple biab calculator. Would I just try a more gentle boil to reduce it in guessing?

 

[pricelessbrewing]

Thanks for the feedback guys. To be honest I'm not sure what my boil off is. I've only done 1 brew and didn't take any notes which was pretty dumb on my part. It was an extract kit and I just topped off in the fermentor. I used 1.25 gallons per hr because that was the default value in the simple biab calculator. Would I just try a more gentle boil to reduce it in guessing?

I recommend a few things:

1) my mash calculator. I really don't like "simple biab calculator" as it's very simple, and is inaccurate on a few calculations.

2)Aim for an intensity between 3-4 on this guide

3) The boil off rate will greatly depend on the width of your kettle, but also the output of your burner.

 

[Chris_Primavera]

Here is a good resource to answer your question

 

[Sadu]

Sparging is great for efficiency although it's an extra step which can complicate a first brew. In this case it means you can add the sparge water to the boil once there has been a bit of boil off and once the hot break is gone, helps you work within the limits of the pot.

I find that boilovers happen when the boil just starts, and when adding any hops. So if your pot is near capacity just add the hops in slowly, and standby with a spoon or spray bottle to attack the foam. Other than that I keep my pot topped right up and haven't had issues.

 

[balrog]

1) I reliably use and highly recommend Priceless Calcualtor
2) I regularly used to mash with volume (water + grist) <=4.5G in 5G pot then pour over or soak in "sparge" and boil <=3.8--4.2g.

You want to mash with at least 1qt/pound but use the calculator to find when you get to 4.5G max water+grain at mash temp. Trust me, trying to use every bit of the pot is a really good way to make a really good mess--stirring, moving, etc.