First All-Grain - Undershot OG by A TON!

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the75

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Ok, so I tried to do a Sculpin clone from a recipe I grabbed from HBA. I'm just breaking in a HERMS system & this is my first all-grain attempt. I way undershot my gravity, ending at 1.043 when my target was 1.067.
I held my mash at 148-150 for 1 hour. There are a couple little things that I wasn't sure of. I didn't know how much sparge water I should have used, but I used my refractometer to periodically check what gravity levels were coming out at. I stopped sparging when I started to get a gravity of 1.015.
Another thing I wasn't sure of was how to check to be sure that I had fully converted. I knew of the Iodine test, but didn't have any iodine. Is it possible that I undershot because I hadn't fully converted yet? is there a way I can test for conversion with my refractometer instead of using Iodine? Another thing I thought might have been a culprit was the fact that I left about 1 & 1/2 gallons in my brewkettle. Maybe I used too much water for sparging. I filled my Mashtun until the water reached the false bottom, then I added 1.5 quarts per lbs grain. Now that I've undershot by so many points, what can I expect? Just a more watered down beer? I'm considering another brewday tomorrow...
Here is the recipe:
Grain
% Amount Name Origin Potential SRM
80 11.00 lbs Pale Malt (2 Row) 1.8L America 1.036 2
7.3 1.00 lbs Cara-Pils Dextrine Malt America 1.033 2
3.6 0.50 lbs CaraVienne Malt Belgium 1.034 24
9.1 1.25 lbs Crystal Malt 10L America 1.035 10

Hops
Amount Name Form Alpha IBU Boil Time
1.00 oz Amarillo Gold Pellet 9.4 45.6 Mash Hop
0.50 oz Warrior Pellet 16.3 35.9 60min
0.25 oz Magnum Pellet 14.4 15.9 60min
0.25 oz Hallertau Northern Brewer Pellet 7.1 7.8 60min
0.25 oz Tomahawk Pellet 16.4 18.1 60min
0.25 oz Crystal Pellet 3.6 2 60min
0.25 oz Centennial Pellet 9.9 5.6 30min
0.25 oz Simcoe Pellet 13.6 7.6 30min
1.00 oz Amarillo Gold Pellet 9.4 0 0min
1.00 oz Simcoe Pellet 13.6 0 0min
2.00 oz Amarillo Gold Pellet 9.4 0 Dry Hop

Extras
1.00 units Whirlfloc Tablets 15min boil

Yeast
White Labs WLP001 California Ale
 
Did you account for any dead space that might be in your MLT? A lot of your sugars might be below your outport if you did not account for the dead space in your new rig. Happened to me on my first couple of batches not to that extreme but I lost a few points. Also it could be your crush. You LHBS might just do a sh1tty crush which could also take another few points off.

These are just a few of the things I came across in my very limited experience that attributed to lower OG.

I'm sure some of the more experienced brewers can shed some more light on your situation. 148-150 temps would definitely not hurt you in your attempt for higher OG those low temps would actually help you in that respect converting more sugar than protein or anything else.

Good luck with the brew tomorrow.

Cheers

Dave
 
I put ur grain bill in to beersmith and looks like u got 43% efficiency instead of 68 u planed on. Conversion usually is completed in 30-45min so dont worry about this right now, I think your problem is grain crash (i never left mine for 2 weeks but i dont think its a big problem) or leaving behind wort in mash tun and BK. As Dave said check your dead space ibn mash tun and BK, maybe you are leavin lots of sugars in those vessels.
 
Said you accounted for deadspace. Sorry didnt catch that part. That eliminates one of the possible causes.

I would ask your lhbs if they are crushing your grains to maybe run them thru the crusher twice if possible. Also take a preboil gravity of the wort in your boil kettle after adding your sparge water. This will be lower than your OG but can be a decent reflection on how mich sugar actually went into your first runnings and sparge water.

Did you end up with more volume than you expected going into fermenter? If your numbers were for a 5 gallon batch and you had 6 after your boil the gravity will be much lower. Also maybe try a thicker water to grain ratio that might be able to help your numbers a little bit.

Lastly if you see after boiling for 60m inutes your gravity is still short of what you are looking for you can always boil for longer. You will end up with less final product but you will be able to hit the gravity you want eventually.

Just throwing a couple other things out there for you to consider if you havent yet.

Hope some of this rambling helps.

Dave
 
If you ended up with 1.5 gallons of more wort than you intended then it sounds to me like you used too much water. Cut the water down by a gallon and your OG should go up.
 
were you fly or batch sparging and at what temp? Did you Verify your Thermometer accuracy? That's a relatively low mash temp and if your thermomter wasn't calibrated you may not have converted as much as you thought.
 
All great suggestions! I really appreciate all the input. When some of you say "account for deadspace under my false bottom", are you referring to not counting the water volume under the false bottom towards my water to grain ratio? If so, yes, I accounted for dead space. I am fly sparging. I didn't calibrate my thermometer accuracy, just trusting the ones that came on my HLT & MT. My digital thermometer took a crap on me, so maybe it's time for a new one. I was using a digital Pyrex for a while, but I think water got into it & ruined it, any suggestions on a good one? I may install a pickup tube in my MT if you all think that will help with any sugars left behind. My outport is sitting about 1 & 1/2 inches above the bottom (it's a 15 gallon kettle), so leaving behind a bunch of sugars seems like a good possibility. It also sounds like I used too much water, but for some reason, I felt that as long as I was taking periodic gravity readings, I'd be able to just cut off the sparge when my gravity started to get too low. I measured my MT water, but not my sparge water for the reason I just stated. I knew I could boil longer, but was weary about my hop schedule being out of wack. Thanks a lot for all these suggestions guys, it's back to the drawing board.
 
Oh yeah, my grains were milled and sat around for 2 weeks... Dunno if that makes a dif,,,

Oops, didn't mean to hit "like" on this. Getting the grains milled a couple weeks ahead of time is fine, I do it almost every time.

I agree with the others: check the crush, and take more gravity readings. Once you have your boiloff rate dialed in, you can calculate the OG from a preboil SG reading, and then decide if you need to boil off more, add DME, etc.
 
My preboil gravity was 1.033. Is there an online calculator to use to get OG? I thought about adding some DME, but didnt like a moron...
 
was this a fly sparge? If so how long did the drain down to 1.010 take?

What kinda water are you using?
 
My preboil gravity was 1.033. Is there an online calculator to use to get OG? I thought about adding some DME, but didnt like a moron...

You don't need an online calculator, but you do need to know your boiloff. And brewing software like Beersmith makes everything much easier.

I'll give you an example with my system, I have a low boiloff rate because I brew indoors on a kitchen stove. I lose 0.5 gallons per hour, then when I cool the wort there's a standard 4% contraction (since cool water is denser than boiling water).

If I start my boil with 6.5 gallons, after a one hour boil I'll have 6 gallons. Then I have to subtract 4 percent of that, so I'll "lose" an additional 0.04 * 6 = 0.24 gallons. So at the end of the day, I'll have about 5.75 gallons of wort.

You just need to multiply the preboil SG by the preboil volume to get total gravity points, then divide by the postboil gravity to get your anticipated OG.

Ex. if my preboil is 1.050, I can say I have 50 * 6.5 gallons = 325 total gravity points. 325 / 5.75 gallons = 57, so my OG will be 1.057.

Try the free trial of Beersmith.
 
Did you add top up water to the fermenter to compensate for the 1.5 gallons left in the boil kettle and then take your OG measurement?

You can sparge down to like 1.010 instead of 1.015.

There is a efficiency calculator here:
http://www.brewersfriend.com/brewhouse-efficiency/

You can just type in your grains, gallons, and your OG and then see how much DME changes the number. There is a simple math formula for calculating how much dme is used to raise x amount of points in x amount of gallons, but I forget.
 
...I'm just breaking in a HERMS system & this is my first all-grain attempt...

There's your problem. But... you already built the system so let's troubleshoot. First, it sounds like you do have a lot of deadspace in your tun. You should thread a street elbow into the drain port of your tun so that it acts as a crude diptube. Deadspace is how much liquid doesn't drainout if you allow a vessel to fully drain. A simple elbow will probably reduce deadspace by a gallon.

Second... 1.5qt/lb is a good ratio INCLUDING the water under your false bottom. You may be mashing just a little too thin.

Third. If you did mash at 148F, you need to rest for a little more than 60 minutes. It may help to ramp your HLT to 180F at the 60 min mark and then let the mash coast up in temp for another 15 minutes. Yes, you can check for conversion with a refractometer by taking your grain weight x 36 and divide by total gallons of water in the mash to get what the full conversion gravity of the mash should be at 100% conversion.

You should fly sparge until you hit your required preboil volume OR when runnings get to 1.008, whichever comes first. Your required preboil volume is your final batch size plus whatever you think your boil off is going to be. For me that's 7 gallons preboil to arrive at 5.5 gallons at the end of the boil (60min). Leaving any wort in the boil kettle intentionally will destroy your efficiency.

Are you maintaining at least an inch of sparge water above the top of your grain bed the whole time you sparge?
 
Ok, so I'm getting there! I fashioned a pickup tube & was able to get much more concentrated wort during sparge. I didn't rest for anymore than 60 minutes, but I'll give that a try next time. I sparged using water at about 165ish, not sure if that was high enough. I got my preboil gravity up to 1.055, but with about 20 minutes left in my boil, I could tell I wasn't going to reach my target, so I added 1 pound of DME. My target was 1.067 & I ended at 1.069. I thought I had enough water over my grains, but during my recirculation, I could see a few grains swirling around, so maybe I need more. After my boil, I ended up with almost 5 gallons & no wort left in the kettle. I used a 1700ml starter, so that brought me close to 5 & 1/4 gallons & most likely took the gravity down a touch (I didn't measure after I pitched). I'm happy to bring up my efficiency so quickly, but I still have a ways to go. While it seemed to be a combination of things from my first attempt, I think a big part of it was that my sparge arm wasn't evenly distributing water over my MT. I was able to keep a closer eye on it this time because I cut a window in my MT lid so that I can watch it closer. I still have a few more equipment tweaks to do, but again, I'm getting there. Thank you everyone for the advice. Bobby, why the dislike for HERMS? I can tell it's going to take some work at getting it dialed in, but the concept is what I liked. Just wondering. Again, thanks everyone for all the help. Now I've got 10 gallons of beer in my fermentors & I have FINALLY done ALL-GRAIN! Woohoo!
 

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