Proper water to grain planning

[pingeyeg]

Not really sure how else to write the title, but explaining it will be easier. I just finished a brew day and ran my mash tun numbers through iBrewMaster, but based on what it told me for a 5 gallon batch (add 15 qt at 171 degrees), I still had 1/2 gallon left of extra water after the 60 minute boil totalling 5.5 gallons of wort. Is it normal to have a discrepancy like that, did I do something wrong? Will the beer taste noticeably watered down?

 

[Clonefan94]

Did you hit your gravity? That's really the only way to know weather it's going to be thin or not.

Double check your boil off rate as well when calculating water. It might not be as high as you thought.

How much wort did you start with pre-boil?

 

[pingeyeg]

Based on iBrewMaster, my OG was estimated at 1.058, but my actual gravity was 1.064. As for boil off rate, not sure how to calculate that. I will need to Google that. I started with 9 gallons into the mash tun and came out with 8 gallons for start of boil. So, I basically got a burn off of 2.5 gallons.

 

[stpug]

Perhaps there is some "waste" values built-in to iBrewMaster that needed to be adjusted for your system - I know that BeerSmith has these built-in to the default equipment profiles. I can see where there might be loss in your HLT, MLT, and BK: HLT can't get all out if using a spigot, MLT could have dead space at the bottom, and BK might leave behind hot/cold break and spent hops.

 

[acidrain]

Taking careful notes so you can adjust for next time is where you're at now. Every bodies system is different.
The boil off rate is the difference between wort collected after mash, and the ready to pitch wort after boil.
The grain absorption should remain a constant number relative to lbs of grain.
At least you went strong instead of weak.
Also, boil off rates will change with atmospheric conditions, so pay attention to that too.

 

[Clonefan94]

Based on iBrewMaster, my OG was estimated at 1.058, but my actual gravity was 1.064. As for boil off rate, not sure how to calculate that. I will need to Google that. I started with 9 gallons into the mash tun and came out with 8 gallons for start of boil. So, I basically got a burn off of 2.5 gallons.

Looks like you hit a higher gravity than expected, so I wouldn't worry about it tasting watery.

As far as the rest of it, you've got all the numbers there, you just need to put those into use next time you brew to hit 5 gallons. Basically, I would just knock 1/2 a gallon off of you sparge water next time, so you start with 8.5 gallons then you should boil down to the 5 you need.

Personally, if you are hitting your gravity, I wouldn't worry about the extra half gallon. I look at that as extra wiggle room. You'll lose some to racking, bottling/kegging etc. So, as long as your gravity is good, then I don't really see an issue with a little extra wort after the boil.