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I keep missing my starting gravity with the new version

rokgoblin

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WTF?!?!  I used to nail my starting gravity damn near every time with the old BeerSmith software version.  Now with the 2.0 version I am missing my OG by several points every time.  My most recent batch was supposed to be 1.066 and it came out 1.060.  Seriously what the hell is going on?  All batches brewed with 2.0 have come out several points below what I am expecting.

<edit> my pre-boil gravity was right on the money 1.054 but post boil is 6 points too low?  I have the correct amount of wort in my primary so what could be going on here.  I am really bummed out and might just have to switch back to the older version until I can get this sorted.
 
I used all my wort from the kettle and siphoned through a large stainless steel strainer into my primary bucket.  I took the gravity reading after my wort had been cooled using a hydrometer (1.060) and a brix refractometer (14.9).

I am stumped as to why the pre-boil was on target but post was 6 points short.  For what it's worth the OG is still within style guidelines, but it's not what a wanted or was expecting. 

The volume into fermenter was a bit lower than expected.  I got just barely over 5 gal...maybe 5.1 gal and was calculating for 5.25.  But shouldn't that mean my wort is more concentrated and would result in a higher OG?

I am also going to post in another forum and will post here if they reply with an answer.  I am just stumped as to what could be wrong when using the new version, or if it even has anything to do with the software calculations.  I imported all my info from the previous version when I installed and made some tweaks to
 
Play with the setting for boil off.  If you have any leftover printouts from the old version, compare them to the current and see if changing the boil off has the desired affect.  Also, look at the setting for your mash equipment.  Could be that something needs to be tweaked in there.
 
All grain....this is my 36th batch I have brewed, of which 33 have been AG batches. 

I collect my full boil volume from the MLT and use no top off water. 

The final runnings of my MLT were 8brix (1.030) and as stated in an earlier post the pre-boil gravity was 1.054 as calculated in BS.  I stirred the BK for about 30 or 40 seconds before I took my pre-boil OG measurement using the refractometer.
 
OK, that all sounds good, trying to double check stuff.  I'm still thinking a setting is tweaked.  Like maybe it thinks your brewhouse efficiency is higher than what it really is.  I actually had the same exact thing happen to me this weekend, oddly enough with the same numbers.  I didn't measure my mash efficiency though.  What revision of version 2 are you running?
 
While it is highly recommended to run the latest release (v2.0.65), I'm not really sue it would have any affect on this issue.  I don't recall anything in the release notes about this kind of thing being worked on.  I will play with my recipe a little and see if I have any other bright ideas.
 
Thanks for the support.  I am also looking at my Brewhouse efficiency, but the older version had me at 65% which I would almost nail my gravity every time.  Version 2.x has me at 65% also.  I will update to the latest build now, but I am not brewing again for at least a week or 2...maybe more  :(
 
Can you post all your volumes (pre-boil, post-boil, into fermenter)?

I agree with Glienhard....your volumes are messed up somewhere.  Could be the boiloff setting, could be process or measurement errors, too.  Have you changed any equipment recently (site glass, boil kettle, dip-stick, fermenter bucket, etc....anything that could affect the accuracy of your volume measurements). 

If you are using different graduations on each vessle (kettle vs. fermenter) have you calibrated them to be sure 1 gallon in each equals the same 1 gallon measurement? 

Are you temperature compensating your volumes?  Hot volume will be about 4% higher than cold volume ---which would make you think you had more preboil water (and sugar) than you really do.  Finishing at 5.1 gallons cold would result in a low OG reading in the fermenter (by about 4%).

You should be able to calculate gravity points at each step.  If you didn't leave anything behind, then the gravity points for each step should add up. 

 
Tom,

None of my equipment is new. 

I thought if my boil off was an issue my OG would be higher rather than lower, especially considering my pre-boil OG was exactly what I was expecting.

My volumes are close estimates based upon marks I dinged into my kettle.  I have yet to make a dipstick for this kettle, but I might go ahead and mark my mash paddle which I also use for stirring my kettle.

I have a 1 gallon rubbermaid container that I have measured and marked 16oz increments on.  I use that to make the final additions to my mash tun and kettle, but up to this point I have always assumed the 1 gallon bottled water jugs I use were indeed 1 gallon.  I use the marks on my BK to confirm my volumes are close to what I need. 

Sadly I recently found out my marks were a bit off on my 1 gallon container, but I have just (today) adjusted them using a reliable graduated container I got from the lab where I work.  I will check my BK in the near future to confirm my dinged marks are reasonably close.

I did not record my post boil volume on this batch, but I did estimate my pre-boil to be 6.7 gallons based on my marks, and fermenter volume to be about 5.1 gallons based on the marks on the fermenter bucket.  I have no way to know how much was lost to hop absorption, but I used 3ozs of pellet hops during the boil, so if you know how to calculate hops absorption that might help.

All of this aside, I'm not sure it's related to equipment because until I changed to the new software my gravity was almost always accurate within a point or 2.  If it ever was off, I was able to confirm that the boil off was lower than expected and I had too much wort after the boil resulting in a lower gravity.

I am not completely excluding the possibility that I am making some error somewhere, but I can't see where that might have happened so I am thinking it might be one of the many new added configuration settings in BeerSmith.

Thanks for the response and I hope I can figure this out.

G!
 
Hops absorption is around 5x dry weight.  So, 3 oz would absorb close 2 cups or so. 

I do the following arithmetic for every step in every batch:

(SG - 1)*1000 * corrected_volume = points

I do this for every running, from each batch sparge. 
Then I do this for the final wort into the boil kettle.

I add the points for each running, and compare with the final wort in the kettle.  They should match.

Then I do it for the final cooled wort while still in the boil kettle.

I compare this to the pre-boil points.  They should match.

Then I do the same thing after I transfer to the fermenter. 

The drop in points should be the same as the volume left in the kettle.

It seems like a lot of measuring...but, it allows me to detect an error right away.  Plus, with the data I can adjust my equipment profile if I learn something new about the equipment. 

If you have this data and post it here, we might be to tell where things are going wrong (either in beersmith or process).

Btw, I use one of these:  http://www.acemart.com/prod4472.html

 
Tom,

I unfortunately don't have all of those measurements available for this batch.  I will try to incorporate those into my next batch.

Here is what I do have:
pre-boil/kettle = 13.7 brix (1.054) - approx volume 6.7gal
post-boil/kettle = 14.9 brix (1.060) - estimated volume 5.2gal
fermenter OG = N/A - volume ~5.1gal

I am not certain on how you take gravity readings during a fly sparge.  Wouldn't you need to mix the wort to ensure you are not getting a diluted reading?  I did take a gravity reading of the final runnings using my refractometer after I collected my full boil volume and it was 8brix (1.030)

So if I fly sparge should I take pre-boil (kettle), post-boil cooled (kettle), and fermenter gravity readings.

Lucky for me I have an Ace Mart less than 5 miles away, perhaps I will go buy one of those pitchers if they have it on hand.
 
Okay, well I batch sparge.  Nevertheless....

The gravity of your initial runnings is critical in determining your conversion efficiency.  So, I would take a gravity reading after vorlauf of those initial runnings.  If you always mash with the same thickness say 1.5 gal/lb, then your initial runnings should ALWAYS have the same gravity.  Any variation is due to some error in the mash (mostly crush, but also pH, dough-balls, temperature control, etc). 

Plus, the numbers you have listed.

Looking at your data:

pre-boil = 362 pts
post-boil = 312 pts

50 pts is large.  That's over a pound of DME that "vanished" during the boil.  Nothing to do with beersmith here.  Just plain old measurement error.  Since both of these measurements are taken with the wort still in the kettle...no extract could have escaped.  Since you use a refractometer, that's pretty hard to mess up in a big way. 

Volume is easier to mess up without solid calibration.  You are looking at a 15% error...to account for the vanished sugars. If you aren't temperature compensating your hot measurments that's 4% error...leaving 11% in measurement.  That's ~1/2 gallon, which can be easy to lose.


 
I think a closer look at my volumes is in order on my next batch, but this still leaves me wondering why all of a sudden after 30+ all grain batches I am not hitting my numbers.  The only thing that has changed between now and previous successful batches is the software. 

I always mash with 1.25qts/lb, and my voume measurements were hardly concise.  I will pay closer attention to my volumes on the next batch and see where that leads.  I have always used the marks on my kettle as my guide to how much volume I have in the kettle and the markings on my bucket as to how much volume was transferred.  My gravity readings have rarely been this far off until now and nothing significant about my process has changed.

I rarely have any leftover wort in the kettle after I transfer to primary, unless I use my autosiphon and stop when I start to pickup trub, etc..  That is the only process difference between other batches and my last few.  I recently started pouring through a strainer to get all the wort and leave the trub and hops behind in the strainer.

I will start to count more closely the volumes and take additional measurements during the process.
 
Cool, good luck.  Use your new ace-mart pitcher to calibrate everything to the same standard. 

 
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