Author Topic: Wrong volumes when adding sugar or extract  (Read 1507 times)

Offline Zelig

  • BeerSmith Apprentice Brewer
  • **
  • Posts: 4
  • BeerSmith 2 Rocks!
Wrong volumes when adding sugar or extract
« on: March 01, 2017, 03:11:44 AM »
Hi!
I'm an all grain BIAB brewer, working on a not-so-big pot on my kitchen stove, and sometimes, when I'm brewing an high OG beer, I use to add some malt extract or sugar to the wort, because there's no space for more grains...
I discovered that in this case, BeerSmith 2 makes a mistake when calculating volumes, because they doesn't change at all if I add DME, LME or sugar or nothing! I suppose that adding "something" to the wort, that will dissolve into it, will cause an increase in volume, right?
In fact I've found that in those cases I always end up with a higher batch volume and - of course - a lower OG than expected...
Am I doing something wrong or is it a bug?
Thanks
Corrado
« Last Edit: March 01, 2017, 03:13:20 AM by Zelig »

Online Oginme

  • BeerSmith Grandmaster Brewer
  • *****
  • Posts: 1903
  • Goats, guitars, and a home brew; Life is good!
    • Longvu LaManchas
Re: Wrong volumes when adding sugar or extract
« Reply #1 on: March 01, 2017, 05:35:45 AM »
You are correct that the addition will cause some increase in volume and that BeerSmith does not calculate it into the volume equation.  Unless you are adding a large amount of LME, this change should not be too great and unless you are pre-diluting your DME or LME, this change in volume will not result in a low gravity reading.  You are adding either a high sugar content solid (in the case of DME)or a very sugar dense liquid (in the case of LME) to a solution with a much lower concentration of sugar.  This will always result in an increase in gravity.

Since you have been getting low gravity readings, I would suggest looking at your efficiency from your BIAB mash.  I find it not unusual to have much lower mash/lauter efficiency when making higher gravity recipes, as the water which remains with the grain also contains a higher amount of sugars.  My typical mash efficiency runs around 86% for most normal gravity recipes, but will drop down as the gravity increases to around 78% for very high gravity recipes (above 1.090).
Recycle your grains, feed them to a goat!

Offline Zelig

  • BeerSmith Apprentice Brewer
  • **
  • Posts: 4
  • BeerSmith 2 Rocks!
Re: Wrong volumes when adding sugar or extract
« Reply #2 on: March 01, 2017, 06:29:20 AM »
Thanks Oginme,
you're right about efficiency, my last batch was expected 1.100 OG considering 5% less efficency than usual. Probably I had to consider 10% less... :-)
BUT, considering the 0,8 liters more volume I had at the end of boil (on a 15 liters batch), the OG error would be much lower! Since usually my evaporation rate is calculated perfectly by BS, I suppose that that should be the volume of the DME (1kg) and sugar (0,3 kg) I've added. I've found a chemical formula that gives me exactly that value if it was all sugar!
I really think that the software should consider that into calculations...
« Last Edit: March 01, 2017, 06:36:07 AM by Zelig »

Offline BeerSmith

  • Brewer, Author, Patriot
  • BeerSmith Administrator
  • BeerSmith Grandmaster Brewer
  • *****
  • Posts: 5183
  • BeerSmith - take the guesswork out of brewing!
    • BeerSmith
Re: Wrong volumes when adding sugar or extract
« Reply #3 on: March 02, 2017, 10:53:02 AM »
The next version of BeerSmith will show LME and DME volumes (actually volumes for all fermentables) and should handle this better.

Brad
Get my new book and podcast from the BeerSmith Blog

Offline Zelig

  • BeerSmith Apprentice Brewer
  • **
  • Posts: 4
  • BeerSmith 2 Rocks!
Re: Wrong volumes when adding sugar or extract
« Reply #4 on: March 02, 2017, 02:18:42 PM »
Thank you very much, Brad. That's good news!

Offline Zelig

  • BeerSmith Apprentice Brewer
  • **
  • Posts: 4
  • BeerSmith 2 Rocks!
Re: Wrong volumes when adding sugar or extract
« Reply #5 on: September 10, 2018, 02:17:35 PM »
Ok, so I have upgraded to BeerSmith 3 and... the bug is still there.  :(

Offline GigaFemto

  • BeerSmith Grandmaster Brewer
  • *****
  • Posts: 253
  • Muonic Matter Rocks!
Re: Wrong volumes when adding sugar or extract
« Reply #6 on: September 10, 2018, 05:14:22 PM »
Yes, this is a big disappointment. The Design tab lists the volume of extract, but the volume calculations don't use it! If the volume is relatively small it isn't a big deal, and if the volume is large enough to matter you can compensate manually by adding less water. There is another bug lurking in here that I hoped would be fixed in version 3 but isn't. If you have an All-Grain recipe with non-zero trub loss, the contribution from extract (LME, DME or sugar) will be over-estimated. The extract is considered to be transferred from kettle to fermenter with 100% efficiency, while the sugars from the grains will be transferred with a lower efficiency due to the trub loss: transfer efficiency = batch size/(batch size + trub loss).

--GF

 

modification