Volume Entries BIAB

Hi,

Ok another Newbie question. I want to get BS2 to do all the calcs, but this means I have to put the right data in that BS2 is expecting.

I do BIAB, 19L batch in 46L pot. I've set up my profile as per attachment.

1) I would typically put 26L water in the pot and heat to Mash Infusion temp before lowering in the bag of grain. I would then heat to Mash out temp and then suspend the bag over the pot to drain, and give it a bit of a squeeze
2) I usually end up with about 24.5L to pre-boil at just below mash out temp
3) I would end up with 19L chilled wort in the fermentor, leaving 1L in the bottom of the pot
4) I would transfer 18L to bottling bucket leaving about 1L in the bottom of the fermentor
5) In the bottling bucket I would add priming sugar in a 0.5L syrup giving me 18.5L to bottle

So, my questions;
1) What numbers do I put in on the Vols tab? Any where else to fill in?
2) For the priming syrup - do I need to add this to the recipe? Or will BS2 incl the amount it calculates when calculating the ABV, etc?

Thanks in advance,
Cameron.

Looks like you have the values you described entered correctly.  The one last item you will need to adjust is your grain absorption.  You started with 26 liters and ended up with 24.5 collected from the mash, so this difference (1.5 liters) divided by the grain amount would give you the amount of water which was retained in the grain.

So, for instance if you mashed in 5 kg of grain, your grain absorption would be 1.5 liters 6 kg or 0.3 liters/kg.  To enter this into BeerSmith, you will need to convert this to fluid ounces per ounce of grain to enter it into BeerSmith.  To shorted the conversion for you, it would be your grain absorption in liters/kg x 1.0585 = fl ounces / ounce.

The path to record this figure (it is a universal setting, affecting all profiles) is 'options' > 'advanced' >> 'BIAB grain absorb', assuming that you are using a BIAB mash profile.

The numbers in the 'vols' tab are there for you to record your readings during brewing which are variations for your planned volumes in your equipment profile.  Unless you plan on changing your planned losses or top off water for a given recipe, just leave these as they appear.

You don't need to enter any priming sugar into BeerSmith for priming.  The program will calculate for you the amount of sugar needed based upon your intended carbonation level and 'bottling volume'.  BeerSmith, as with other software programs, does not include the priming sugar in the calculation of ABV, since the actual production of alcohol from carbonation is small.

Thanks!

And you just solved another problem for me! I had imported all my recipes, including two in progress - I couldn't work out why it was wanting me to add sparge water - I now know there is a little tick box in the mash profile. This didn't get ticked on the imported recipes.

So one last question - as I want to capture actuals, which should I fill in - for example I would expect to have to capture actual water from mash in order to calc mash efficiency, but is this rather calculated from measured pre-boil minus kettle top-up?

TIA.
Cameron

The data you want to capture is on the 'sessions' tab.  The 'meas pre-boil vol' will be the amount you collected from your mash after you add your top off water.  BeerSmith will subtract the amount of top off water to calculate the mash efficiency from this number.  If your top off water is different from how your equipment profile is set up, you can change it on the 'vols' tab to reflect you actual top off volume.  Your gravity reading from your wort collected from the mash should reflect the more concentrated sugars (i.e. higher gravity reading) than your pre-boil volume which would contain your top off water to the kettle.

Hi,

I'm capturing my first batch and it's not making sense to me. I attach the BSMX file for reference.

1) Mash Eff seems to be calculated from Meas Pre-Boil Gravity and Meas Pre-Boil Volume BEFORE Kettle Top-Up. Is this correct? Previous response says it should be after kettle top-up.
[I collected 6.8L of wort @ 1.051. If I add up max sugar points excluding DME which I added later to correct OG I get 146.6 pts max. My 6.8L is 1.8gal so max of 146.6/1.8=1.081, 70%=1.057, my 1.051=62.5%]

2) Brewhouse Efficiency and others seem to ignore post-boil additions. When my OG was low due to poor extraction I added 300g DME and ticked the "add after boil" box. It seems to be using OG into fermentor & meas batch size to calculate BH Eff. However, doing it this way, the DME seems to also get ignored in the ABV calc, attenuation, etc.

Apologies if I'm doing something odd.

Regards,
Cameron.

I've been trying to work through your results. 

You got 6.8 liters of wort at a gravity of 1.051 according to what you have listed.  BeerSmith assumes that this volume includes the 1.7 liters you used to top off the fermenter so it gives you a lower than you actually achieved mash efficiency.  Since the program predicts a gravity of 1.044 from the mash and you achieved 1.051 and it predicted 7.03 liters from the mash (8.73 - 1.7 top off), your actual efficiency was 70% * (51 * 6.8) / (44 * 7.03) = 78.5%.  You didn't enter the gravity of the wort after you topped off the boil kettle, which if you added 1.7 liters to the 6.8 would have given you 8.5 liters of pre-boil wort.  When I enter this into the pre-boil gravity, I get a calculated mash efficiency of 78.2% which is close enough.

To get a true value, you need to enter the pre-boil volume with the top off water.

Now on the other end, you don't list the pre-boil gravity, which should have been 1.040 if you had added the 1.7 liters listed on the volumes tab for boil kettle top-off. 

Is the OG reading you have listed as 1.073 the gravity before you added the DME?  If I take out the DME addition to get to the orginal recipe, it gives a target of 1.065.  Is this what you were aiming for? 

Yes, the brew house efficiency is defined by the gravity and volume into the fermenter versus the potential from the grain bill including post boil additions.

The problem with the post boil addition of DME, is that BeerSmith defaults to the brew house efficiency you have in your equipment profile, so when you add it later to compensate for your lower efficiency, the calculation lowers the sugars from the mash to compensate for the lower demand.  The couple of times that I have had to make post boil additions of DME, I list it in my notes for the recipe but do not add it to the recipe so that the calculation for efficiencies is not thrown off.  I later make a copy of the recipe, add the DME to it, and then recalculate the efficiencies to reflect my actual values.

By calculation, if your boil off was 3 liters, then your pre-boil gravity of 1.040 would have left you with a gravity reading of 1.056 post boil.  Your addition of .3 kg of DME then raised the gravity by 17 points, which calculates out to where you ended up.

In short, the program is working, but is slaved to the original efficiency that you gave it as a target.  Post brewing additions added to the recipe throw off the calculations you originally made.

Thanks Oginme. I appreciate your time and help. Hoping you can answer a couple more - I believe the software is working and I just need to understand;

1) Why if I change the Kettle Top-Up water on the Vols tab - doesn't the mash efficiency change. Is there a point at which the values get "frozen"?
2) I can follow your approach on the DME. I have done this before in Brewers Friend. For the interest of clarity, how does BeerSmith expect you to use the "Add after Boil" checkbox - or more correctly, capture actuals for gravity correction? Dilution I would use "Top Up Water" option and add to batch size.

And yes, you worked it out right, 6.8L@51, +1.7L Kettle = 8.5L, 2.4L boil off and cool = 6.1L@55. Then Gravity correction said to add 300g DME to get 1.073 target.

When you change the top off water, the mash efficiency does not change because you are still ending up with the same amount of sugars from the mash to make your final amount of sugar into the fermenter.    If you take your 0.5 liters of top off water [with expected gravity of 1.044 from the mash with 8.03 liters of wort collected] and zero it out, you will get an expected gravity of 1.042 with 8.75 liters of wort collected on your sessions page.  The mash efficiency does not change, the expected volume and related gravity do change.  Your mash efficiency is set by your input for brew house efficiency in your equipment profile.

I use the 'add after boil' checkbox all the time for sugar additions.  It calculates this properly within the program.  Once you start brewing and you need to bump up the amount of sugars (through dme or other sugar addition), adding this amount to the recipe only causes the program to recalculate the amount of sugar drawn from the mash.  Again, this is controlled by your overall brew house efficiency.  So if you take your recipe where you just zeroed out the top off water to check my numbers on gravity and volume from the mash and zero out the DME, you will see the expected post mash gravity rise to 1.051 to compensate for the loss of the sugars from the DME. 

The thing to remember is that the brew house efficiency and volume to the fermenter are the keys to the calculations from a given recipe of materials.  As simulation software, BeerSmith has N equations to solve and N+1 variables.  It requires the user to input the brew house efficiency and volume to fermentor to give it the N-1 variables to solve those N equations.

So changing anything within the recipe will change where the program calculates the sugars to come from and how the water balances out through the process using those user set variables.  It is just the way the program works.