Question about end of boil volumes

Post #1 made 6 months ago
My last brew Amarillo Pale Ale (2nd BiAB attempt). Had a specific gravity reading of 1.04 (low). Although I didn't record the volume in the end of boil I think my predicted evaporation rate was much less then predicted (that is....I ended up with more volume). For my next brew I'm going to record everything much better and I have already recalibrated my brewing pot WRT to volumes. In retrospect I wish I had recorded better :(

If I'm right about evaporation rate and it wasn't something else. How can I deal with this next time at the time of brewing?

Boil longer until desired volume achieved? Add sugar (DME)?

Thanks in advance.
Last edited by Ninkas1 on 06 Feb 2018, 21:37, edited 1 time in total.

Re: Question about end of boil volumes

Post #2 made 6 months ago
Hey Ninkas1
I see nobody else has weighed in here, so I'll give it a go. If I"m interpreting your post correctly you ended up with a larger VAW than called for and therefore a lower GAW, right?, I would guess that one of two things occurred: either you made an error in filling in your Biabacus or your boil wasn't vigorous enough. Generally I would suspect that your boil wasn't "vigorous" enough - a really ambiguous term for sure. Don't be reticent to crank up the heat and boil the heck out of your wort for the full 90 minutes (assuming you are watching it constantly so no boil overs occur - be safe!). You can easily adjust your GAW if you've boiled off too much. Others more knowledgeable than me will respond.

Please post your recipe so that others can review it and see if there are any input errors, then try it again! :thumbs:
Last edited by Streamer on 07 Feb 2018, 12:41, edited 2 times in total.
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Re: Question about end of boil volumes

Post #3 made 6 months ago
@Ninkas1 , as @streamer mentioned, don't hesitate to supply as much detail as you can including your BIABacus file. (Just had a glance at your prior posts and I think you did use the BIABacus).

If you post more detail, we can soon see if you are worrying about nothing or faster identify any major problem.

For example, you might be worried that your original gravity was 1.040 instead of say 1.045. The beer will be fine. However, if it was meant to be 1.060, then we need to make a solid plan before you brew next.

You mentioned recording better. This is a very good point especially when you are starting out. A good mantra is, "Never trust a single reading on a single brew." There are many ways we can error on a single brew or a single reading. Multiple gravity and volume measurements throughout a brew will let you know if you've made a one-off error (for example, incorrectly weighing out your malt.)

Without more info, at this point in time, we really can't tell if The BIABacus is under-estimating your evaporation rate. On the next brew, aim to take double-check every measurement. If you search for posts written by me on this site containing the term "double-check," I think you'll find some instructions on what measurements are important.

Last edited by Pat on 11 Feb 2018, 18:55, edited 1 time in total.
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