OG was way off from Beersmith

[eryk4381]

For some reason this weekend when I brewed an all grain batch it came out way different that I had calculated. I was making a strong dry IPA and beersmith had told me that it would have an OG of 1.070 and Pre boil gravity or 1.070. I had mashed at 148 for an hour then brought it up to about 156 to fly sparge (I wanted it at 170 but never got it that high). I took my pre boil reading to get a sense of where I was at and came up with an OG of around 1.036!!! WTF!! I figure I would get more without even crushing the grains that's so bad.
I am not sure what I could have done wrong here. Any ideas?
I attached my brew sheet.

Also, here are my notes during the brew session:
Used Cascade hops instead of orginal Centennials at same schedule.
Used Willamette hops instead of orginal Amarillo at same schedule.

7.40 gallons Mash water needed
6.33 gallons Sparge water needed

Mashing @ 148 for 1 hour
Bring up to 156 for 10 mintues
Fly sparge @ 170

Used two different yeast; One for 4 gallons each. Both as starters.

did not end up getting the 170 on the fly spare; I got about 154 at best.
saved runoff from the rest of the mash to make a pale

Add corn sugar 10 min till flame out

 

[billl]

How are you measuring your gravity?

 

[matt-tastic]

I went small when switching to AG, and built a convertible mash tun (meaning i could take it apart and put it on a larger tun) at 2 gallons. My biggest issue was my Brewhouse efficiency. mine was at 70%, and I was still way lower than my targets. yours at 75% is probably too high as well.

Another thing, initially when i was trying to figure it out, I was taking gravity readings with hot wort, and not calculating for the temp changes. Once I calculated for temp differences (I use this calculator), I was closer, but still off. A combination of these may be partially to blame.

Again, these are from my experience (with 1 highly irregular setup), so none of this may apply to you.

 

[bknifefight]

If this wasnt your first AG batch and you previously had some consistency with your efficiency, I would look into how you took the gravity reading and it's calibration.

If this is your first batch doing AG, it's hard to narrow down where you could be running into an issue. How was your crush?

 

[eryk4381]

How are you measuring your gravity?

Using a Hydrometer and adjusting for Temp and hydrometer adjustments

 

[eryk4381]

If this wasnt your first AG batch and you previously had some consistency with your efficiency, I would look into how you took the gravity reading and it's calibration.

If this is your first batch doing AG, it's hard to narrow down where you could be running into an issue. How was your crush?

I have been doing all grain for awhile. Most of the time i see my efficiency a bit low but never this bad. Really insane.

 

[eryk4381]

Could it have been from the loss of sugars in the deapspace? It looks like I may have an issue with deadspace as it may be around 1-2gallons

My drawing is remedial at best but it show what I had setup basically and I think the way the mesh may have been stirred up into the mash and not laying at the bottom (plus i had and extra length of vinyl tubing in there) it did get all the good sugars at the bottom.

 

[forsaken541]

How was your grain? I recently had the same issues brewing a Porter. When adding grain to mash tun cooler I noticed it was ground pretty fine not just cracked. I think mine was from stuck sparge due to floury grain bed.

 

[SudsyPaul]

Your OG is WAY low... That sort of loss of efficiency seems strange.

Did you stir your wort before measuring? There can be stratification when you're sparging, and maybe you just measured the late runnings?

I batch sparge, but I don't take my reading until everything is in the kettle and has been stirred up super-well. Forgot to stir a few times and almost dropped a deuce when my readings were 20-30 points too low.

 

[eryk4381]

How was your grain? I recently had the same issues brewing a Porter. When adding grain to mash tun cooler I noticed it was ground pretty fine not just cracked. I think mine was from stuck sparge due to floury grain bed.

I was fine but no more than normal..

 

[eryk4381]

Your OG is WAY low... That sort of loss of efficiency seems strange.

Did you stir your wort before measuring? There can be stratification when you're sparging, and maybe you just measured the late runnings?

I batch sparge, but I don't take my reading until everything is in the kettle and has been stirred up super-well. Forgot to stir a few times and almost dropped a deuce when my readings were 20-30 points too low.

Ha, its possible as I almost dropped a deuce myself!!
I don't remember stirring it at all before taking any readings. I did split the sparge runnings into two tanks before combining them both into the kettle and took a reading form both of those and got 1.040 in both. But still at no time did I stir. You think that would do it?

 

[SudsyPaul]

It's definitely possible that all you measured was the top sparge water and not the more dense sweet wort which would have sat on the bottom. I don't know what your sparge setup looks like, but if your hose isn't sitting on the bottom and stirring things up as it flows, I'm gonna guess that you had stratification.

Another indicator of stratification is that the pot with your 60min mash is the same OG as your sparge running pot. Those should be 2 drastically different numbers. I get 1st runnings at 15 brix and 3rd runnings at like 8 brix. Again, I batch sparge, so I could be missing something with fly sparging

 

[matt-tastic]

Learn something new every day. while it makes perfectly good sense, the fact that the sugars would settle from first to second running would be WAY down on my list of things to check too.

NOTE: Stir before reading.

 

[Yooper]

Using a Hydrometer and adjusting for Temp and hydrometer adjustments

Remember that if you took the preboil SG at above about 100 degrees, that correcting for temperature is still inaccurate. In order to get a good reading, the sample must be cooled to under 90 degrees or so, THEN temperature corrected. That might be way the preboil gravity is so low.

Did you take a post-boil OG, after the wort cooled? I didn't see that info, and might have missed it.

 

[JeepDiver]

hard to read the image, but looks like it says you should have ~9 gals pre boil. With 7.4 gallons in the Mash, and 6.3 in the sparge, I would think you are way over that, unless you have a lot of dead space and are losing a lot of sugar there. Do you know how many gallons you had pre boil. Also as Yooper mentioned, what was your post boil readings and vol

 

[eryk4381]

Remember that if you took the preboil SG at above about 100 degrees, that correcting for temperature is still inaccurate. In order to get a good reading, the sample must be cooled to under 90 degrees or so, THEN temperature corrected. That might be way the preboil gravity is so low.

Did you take a post-boil OG, after the wort cooled? I didn't see that info, and might have missed it.

No. basically I took about 4-5 gallons in the first fermenter (about half what I needed. Started the second one and then pretty much immediately checked it so it was, I'm sure, way over 100 degrees. Which I'm guessing by your last post wont work?

 

[Yooper]

No. basically I took about 4-5 gallons in the first fermenter (about half what I needed. Started the second one and then pretty much immediately checked it so it was, I'm sure, way over 100 degrees. Which I'm guessing by your last post wont work?

Right. SG readings taken over 100 degrees are so inaccurate (even with tables and conversion software) as to be useless.

Also, volume must be taken into consideration. An OG reading is useless if you don't know the exact volume.

Next time, take a preboil SG reading (cool the sample first!) and check the volume. You can mark lines on your boil pot, or measure in a bottling bucket and then transfer to your kettle, etc. That's needed to see your mash/conversion efficiency.

Then when all done, take an OG reading of the total cooled wort, along with the volume. We can then figure your exact efficiency and help you figure how where the problem may lie.

 

[matt-tastic]

Right. SG readings taken over 100 degrees are so inaccurate (even with tables and conversion software) as to be useless.

Also, volume must be taken into consideration. An OG reading is useless if you don't know the exact volume.

Next time, take a preboil SG reading (cool the sample first!) and check the volume. You can mark lines on your boil pot, or measure in a bottling bucket and then transfer to your kettle, etc. That's needed to see your mash/conversion efficiency.

Then when all done, take an OG reading of the total cooled wort, along with the volume. We can then figure your exact efficiency and help you figure how where the problem may lie.

Yooper, Is there a good way to do this? i've looked, and didn't really see any advice on marking a kettle. I thought to use a scratch awl, as it would be permanent, but would make a place for stuff to live in the pot (then it gets boiled, so it may be a moot point). marker wouldn't be a permanent solution either...

I've just taken to marking my mash paddle & spoon, which seems to have worked well enough.

 

[JLP]

Matt, marking your spoon is the most common sense way about measuring your wort level. Everything else can turn out to be an infection hazard or a good guestimation.

 

[matt-tastic]

Matt, marking your spoon is the most common sense way about measuring your wort level. Everything else can turn out to be an infection hazard or a good guestimation.

I did something the common sense way!

 

[GrogNerd]

my 30qt pot is 15 inches tall. makes it simple; 2 quarts per inch.

got a stainless steel ruler, super easy to measure volumes (and keep sanitized)

and OP: you say "OG of 1.070 and Pre boil gravity or 1.070" that pre-boil measurement can't be right?

 

[unclevername]

my 30qt pot is 15 inches tall. makes it simple; 2 quarts per inch.

got a stainless steel ruler, super easy to measure volumes (and keep sanitized)

and OP: you say "OG of 1.070 and Pre boil gravity or 1.070" that pre-boil measurement can't be right?

I have the exact same setup and method for checking volume. Easy easy makes me happy happy.