BIAB and Beersmith 2 question

[ToddStark]

Trying to do my first BIAB and first BeerSmith as well. I have a 10 gallon pot. I have put in this information into BeerSmith but when I look at the Mash tab it says "Mash Volume Needed 9.65g". My recipe calls for a little over 10lb of grain. I don't see how I can fit both into a pot. Won't 10lb of grain displace more than .4 gal of water?

I have tried selecting BIAB, Medium, Light, and Full body under the Mash Profile but that doesn't seem to change the requirements for 9.65g of mash water.


What am I missing here? How can I fit 10lb of grain into my 10 gallon pot and get efficient BIAB mash extraction?

 

[LLBeanJ]

Beersmith already factors the grain bill into the mash volume calculation, so total mash water + grain - expected losses will require 9.65 gallons of mash tun volume. With that said, it'll fit, but you will be pretty close to the top of the kettle.

What is your expected boil-off/hour and what is your grain absorption rate set to in BS? I have a 15G kettle and my boil-off is 1.25G/hour and I would expect a 10G kettle to be less than that. My BIAB grain absorption is set @ .46 fl oz/oz (instead of the default .586). If you're using the default, I'd lower it as I've found BS overestimates how much water you will need, especially if you plan on squeezing the bag. Also, make sure the BIAB box is checked in the mash profile so it uses the BIAB rate instead of the normal rate.

Under the Vols tab, do you have anything entered for Tun Deadspace or Trub Loss?

 

[ToddStark]

I didn't change the following but are...
What is your expected boil-off/hour--1.42
grain absorption rate--.76
Evaporation rate --17.6% per hour

Vols Tab--
Tun Deadspace =0
Trub loss = .90

 

[Smellyglove]

I didn't change the following but are...
What is your expected boil-off/hour--1.42
grain absorption rate--.76
Evaporation rate --17.6% per hour

Vols Tab--
Tun Deadspace =0
Trub loss = .90

17.6% evap pr hour?

You can do WAY less, use the lid for instance, partially cover the pot or almost completely cover it, and get it to a simmer +. No need to have a vigorous boil. I feel that anything over 10% is way to much. (but boil vigor and evap rate is not the same) This way you don't need as much strike/sparge water.

You need some more grains if going less evap though. But grains don't occupy as much space you'd think pr extract point.

and as LLbeanJ stated. BS takes this into account. But, I've understood that those numbers starts to be correct after the grains has hydrated and sunken to the bottom. Inital dough in will bring you over this target.

 

[LLBeanJ]

I agree with @Smellyglove the evap rate seems a bit excessive. Maybe lower your boiloff to 1.0 or maybe 1.1 and see how it goes unless you already know that is what your BK will boil off. Definitely lower the absorption rate... try .5 and see how that works. My Trub loss is zero, but I dump the whole nine yards into the fermenter. Leave it at .9 if you are planning on leaving that much behind in the BK at the end of the boil, but if you plan on dumping it all into the fermenter, drop it to zero. All of these things will lower your mash volume and the amount of water you will need.

 

[ToddStark]

Up till now I have only done extract brewing but have always used a partially covered pot during the boil. The evaporation per hour calculation came default from BeerSmith, I didn't input that and I wouldn't have been able to even provide a guess on what the evaporation would be if I hadn't seen the setting.

When i had done my initial investigation on doing grain brewing, I was under the impression that a 10 gal pot would be fine for a 5 gal BIAB batch. This is why as I figure out my first grain recipe I was a bit confused about putting in 9.65 gal of water and 10 lbs of grain into a single pot. I definitely need streamline this software to make it all fit. LLBeanj initial response did help out a bunch. I didn't realize the 9.65 number was a combination of the grain and water. Now after looking further I found the number I was looking for that shows I need to start with 8.3 gal of water. This will still be a tight fight so any other information that might be able to help me streamline this and give me more head space would be greatly appreciated.

 

[ToddStark]

All great information guys, thank you... Currently trying to find where I can change absorption rate to .5 and evaporation rate to 10% in the software to see how that helps. Brad seems to have hid those values well

 

[Smellyglove]

Up till now I have only done extract brewing but have always used a partially covered pot during the boil. The evaporation per hour calculation came default from BeerSmith, I didn't input that and I wouldn't have been able to even provide a guess on what the evaporation would be if I hadn't seen the setting.

When i had done my initial investigation on doing grain brewing, I was under the impression that a 10 gal pot would be fine for a 5 gal BIAB batch. This is why as I figure out my first grain recipe I was a bit confused about putting in 9.65 gal of water and 10 lbs of grain into a single pot. I definitely need streamline this software to make it all fit. LLBeanj initial response did help out a bunch. I didn't realize the 9.65 number was a combination of the grain and water. Now after looking further I found the number I was looking for that shows I need to start with 8.3 gal of water. This will still be a tight fight so any other information that might be able to help me streamline this and give me more head space would be greatly appreciated.

Under the "Vols" tab you can see all the different volumes in one place. Indeed, if BS tells you that "mash volume needed" = x, that x it is, with both water and grains. But keep in mind what I mentioned earlier. If you dump all the grains in at once, you will exceed this volume.

In the mash-tab you'll see which volumes of water to add when.

I'd suggest you pour a fresh kettle of water, start to boil, then dial in the boil intensity, then measure before and after volume (or weigh it). Remember that there's a 4%-ish volume difference between tap-water-temp and boil temp. Enter the boiloff into Beersmith. Boil for at least half an hour and multiply to get boiloff rate pr hr, Dissolved air in the water will give you a more vigorous boil at the start, so you can only do this once or twice with the same water to get ballpark numbers.

 

[Smellyglove]

Absoprtion rate is under Tools - Advanced. Make sure you use the box which is correct for your equipment setup. If you've checked he boks with "I'm doing BIAB" or whatever, then change the biab numbers. Keep in mind that if you check the box with BIAB there is no sparge option. It takes into account that you mash with full volume. So know what you're doing, so you dont change the wrong absorption numbers. To be safe, change both.

Evap is within you equipment profile.

 

[LLBeanJ]

You'll find the absorption rate setting under Options ---> Advanced. Boiloff rate is under the equipment profile.

 

[ToddStark]

Thank you both very much for spending part of your Sunday with me on this issue. I now have some very workable numbers to start with and you have given me some great advice on how to test my water evaporation rate ahead of brew day.

 

[kevin58]

It is highly recommended that you set up your own equipment profile and mash profiles in order to get Beersmith to work properly. Even Brad Smith who write the software says the profiles that come with the package are just suggested starting points.

Equipment Profile Tutorial #1:

Equipment Profile Tutorial #2:

BIAB Mash Profile Tutorial:

 

[Scuttle_it]

I had similar jitters about the high gravity batch I recently did. Beersmith said I'd have 1.4gal free space, and after adding the water, I didn't believe it. Added the grains, and lo and behold, the results were spot on!

 

[FunkyMunk]

I had an issue with this recently, after adding my grain, my volume came to the very top of my kettle and I found I couldn't get a good stir without sloshing liquid and some grain out of the kettle. In retrospect I should have withheld some of the water until after the mash, and just had a thicker mash. What happened was that my total water volume was higher than it should have been, because I failed to account for the fact that the total water volume given by BS is the heated volume, and I measured my water at room temp. Of course as soon as it came to strike temp I realized I suddenly had a higher volume due to expansion.

 

[Smellyglove]

I had an issue with this recently, after adding my grain, my volume came to the very top of my kettle and I found I couldn't get a good stir without sloshing liquid and some grain out of the kettle. In retrospect I should have withheld some of the water until after the mash, and just had a thicker mash. What happened was that my total water volume was higher than it should have been, because I failed to account for the fact that the total water volume given by BS is the heated volume, and I measured my water at room temp. Of course as soon as it came to strike temp I realized I suddenly had a higher volume due to expansion.

For mashing BS calculates water volume as "cold" afaik. It's only during the boil process it calculates in the +4% volume offset from cold temps..

So if you want to do it correctly you have to add about 3% less water if you dough in in the 65C + area.

 

[Oginme]

For mashing BS calculates water volume as "cold" afaik. It's only during the boil process it calculates in the +4% volume offset from cold temps..

So if you want to do it correctly you have to add about 3% less water if you dough in in the 65C + area.

Actually, if you follow the water balance on the 'vols' tab, you will see that the water volume is actual measured hot. The program starts with the volume in the fermenter, adds the loss to trub and chiller and THEN applies the volume for thermal expansion. From that point on, the program does not reduce the volume back to room temperature.

The easy test is to set the thermal expansion to 0% in the equipment profile within the recipe and see the initial infusion volume drop.

 

[Smellyglove]

I asked brad about this. He said that when measuring strike water the software gives you a "cold" number, and the only hot (+4%) number is boil. I might be confused, but that's what he told me afaik.

 

[Smellyglove]

"If my strike temperature is at 65c. Should i take my strike volume and deduct 2% from that volume since I'm filling with cold tap water?

Pre boil volume. at what temperature is this calculated? Is it at my mashout-temperature? If I measure my preboil-volume and it's on point with what BS gave me, do I have to take account for any expansion either way?

Post boil volume. Is this right after boil (+4% comparing to cold water?) Let's say I don't mash out, then my preboil volume will be at +2% thermal expansion, is it correct to measure the post boil volume at +4% thermal expansion? I guess that measuring post boil at +4% wil give me 2% more volume comparing to the preboil which is at 2% expansion?"

Answer:

Yes you do get a slight expansion of water at mash temps but to be quite honest I've never worried much about it. I generally
measure the water cold, heat it and use it. In BeerSmith itself only the cooling loss from boiling is built into the software, so if you
measure your boiling volumes hot you should get pretty close assuming the volumes in your equipment profile are correct.

This is from an email-correspondance a few year ago. I made the text in italics for emphasis.

 

[Oginme]

"If my strike temperature is at 65c. Should i take my strike volume and deduct 2% from that volume since I'm filling with cold tap water?

Pre boil volume. at what temperature is this calculated? Is it at my mashout-temperature? If I measure my preboil-volume and it's on point with what BS gave me, do I have to take account for any expansion either way?

Post boil volume. Is this right after boil (+4% comparing to cold water?) Let's say I don't mash out, then my preboil volume will be at +2% thermal expansion, is it correct to measure the post boil volume at +4% thermal expansion? I guess that measuring post boil at +4% wil give me 2% more volume comparing to the preboil which is at 2% expansion?"

Answer:

Yes you do get a slight expansion of water at mash temps but to be quite honest I've never worried much about it. I generally
measure the water cold, heat it and use it. In BeerSmith itself only the cooling loss from boiling is built into the software, so if you
measure your boiling volumes hot you should get pretty close assuming the volumes in your equipment profile are correct.

This is from an email-correspondance a few year ago. I made the text in italics for emphasis.

Right. So what he is saying is that he does not think that the difference between room temperature measurement and strike water temperature is enough to worry about. The volume of the thermal expansion ends up getting baked into the numbers when you balance the volumes out in the system. You will note that he does NOT say that the volume is measured cold, just that he does not think the amount of expansion makes enough of a difference in his process.

The software itself calculates the strike water volume at a fully expanded number, as if the water was at boiling. I've gone through the calculations many times and confirmed this. The issue that I have is that the volume is not corrected to temperature, but is either at cold (room) temperature or at fully expanded (boiling) and there is no scaling in between. Even a linear scale (though still off) would be closer than a simple digital on or off of the thermal expansion.

BTW, if you follow the maths through on the sugar balance, you can see where this throws another error into the system if you measure the pre-boil volume right at mash out temperature. The balance takes this volume (expanded) and calculates the gravity readings from the (cold) fermenter volume and gravity.

 

[ToddStark]

It is highly recommended that you set up your own equipment profile and mash profiles in order to get Beersmith to work properly. Even Brad Smith who write the software says the profiles that come with the package are just suggested starting points.

Equipment Profile Tutorial #1:

Equipment Profile Tutorial #2:

BIAB Mash Profile Tutorial:

Thanks Kevin. Yes, that was one of the first things I did was try and set up the software for my equipment. With all the help you guys have provided and a couple of batches under my belt using Beersmith, i am sure I will get things a bit more precise. I appreciate your input.