Missing OG by 20+ Points - Help!!

[Mahanoy]

I've brewed three or four batches of a Rye IPA that borders on being a double IPA and each time I've brewed it I've missed my OG by 20 points or more. This is the only beer I've ever had trouble with in terms of hitting my OG (my system's efficiency is generally in the range of 65-70%). It's frustrating because it's a lot of grain and I'm not getting the bang for my buck. I don't know what the issue is with this beer in particular, but something is going on that's causing problems and I really want to figure out what that is so I can fix it! Here's the malt bill and my mash and sparge schedule:

10# 2-row
4# Rye malt
1# Crystal 40
0.5# Crystal 80
0.25# Carapils
0.25# Special B
0.25# Rice Hulls

Mash - 6 gallons @ 164 (target 152) - 60 minutes (stir every 15 minutes)
Batch Sparge - 4 gallons - 45 minutes to collect wort
1.5 qt/gal
14% grain absorption rate
10% boil off/hour
(All of this per MoreBeer's Sparge Calculator: Sparge Water Calculator | MoreBeer)

I lose 1/2 gallon in the mash tun and another gallon to trub left behind in the boil kettle.

I ended up with 7.75 gallons pre-boil and 6 gallons into the carboy.

When I brewed this beer the other day my software (BeerSmith) put the OG at 1.071. When I checked the gravity before I pitched the yeast it was 1.050. Missing gravity by 20 points is a lot!!

I have no idea where I'm losing this many points. Like I said, I don't have this problem in any other beer on this system - this is the only one that comes in so much lower than it should. I'm at a loss and I would really like to figure out how to hit my OG target for this beer.

 

[VikeMan]

When I brewed this beer the other day my software (BeerSmith) put the OG at 1.071. When I checked the gravity before I pitched the yeast it was 1.050. Missing gravity by 20 points is a lot!!

What was your assumed Mash Efficiency (not brewhouse efficiency) used by Beersmith? Was it based on other beers you've made that had smaller grain bills?

What was your actual post-boil kettle volume, and what was Beersmith's post-boil kettle volume?

 

[bracconiere]

someone else will have to say i'm stupid....but maybe the mucus (whatever) from the rye malt, and stiring is locking up the enzymes....


i never stir my mash?

 

[IslandLizard]

Did your mash get plugged up due to the rye?

Did you use a cooler mash tun and no recirc?

 

[jschein]

I do a similar recipe, how long does it take to get to your target mash temperature? Your recipe shows a 12 degree heat loss from mash in to target mash temperature. I heat my water to 156 and it gets me to 152. You may also want to add a pound of rice hulls with that high percentage of rye. I also use a lot or rye 30% is my sweet spot but have done 40 percent with a 90 minute mash

 

[jschein]

someone else will have to say i'm stupid....but maybe the mucus (whatever) from the rye malt, and stiring is locking up the enzymes....


i never stir my mash?

Funny you say that, the more rye I use the more it looks like brains flouting around

 

[IslandLizard]

Your recipe shows a 12 degree heat loss from mash in to target mash temperature.

Not the OP but "strike temp" means very little, all depends on the system and method.

For example, I underlet the mash. My 5 gallons of strike water is 178F (!) to arrive at the intended 154F mash temp a few minutes later. Using a rectangular cooler mash tun.

 

[jschein]

Not the OP but "strike temp" means very little, all depends on the system and method.

For example, I underlet the mash. My 5 gallons of strike water is 178F (!) to arrive at the intended 154F mash temp a few minutes later. Using a rectangular cooler mash tun.

Actually that is what I was getting at maybe it takes 15-20 minutes to reach the target temperature, or the OP has a faulty temp probe.
Other issue could be channeling hence more rice hulls

 

[IslandLizard]

[...] stiring is locking up the enzymes....

That's doesn't happen. It actually helps releasing them through faster and more thorough hydration.
A gooey mash should be stirred as if it owes you money, and then some. Stirring the mash reduces viscosity, making it more fluid.

I brewed a 50% Rye (malt) beer that took over an hour to lauter 3-4 gallons from, looked like wet cement. Much stirring and adding more hot water helped eventually. The 2 batch sparges were slow too, but got better with time. I forgot to implement a beta-glucanase rest.

 

[Mahanoy]

I always hit my mash temp in this system (10 gallon igloo cooler with a false bottom), and I've never had a stuck sparge with rice hulls (knock on wood). Since I started stirring my mash every 15 minutes I've noticed a higher mash efficiency on every beer except this one. However, I've noticed that I'm getting a bit more wort out of the second runnings from the sparge than I should be getting, so maybe I need to dial back the sparge water a bit. But that won't account for missing OG by 20 points! This is the only beer that I'm messing up, and it's also the only beer I brew with this much rye. Maybe that has something to do with it?

 

[bracconiere]

I forgot to implement a beta-glucanase rest

sounds like something to think about...could also try to mash the rye malt on it own in a mini mash then add that to the main mash after 30 min or so....

 

[rjhoff]

Are your grains unique for this beer? I’m developing a rye IPA recipe where I missed OG and also pre-boil SG, so clearly a mash issue. Im using grain (2 row and rye) from a local maltster regionally grown and found out the kernel size is small (Requires a mill gap .034 or less, I was at .039) so I’m banking on a 2 pass mill at .038 next time hoping it will fix things.

 

[IslandLizard]

Are your grains unique for this beer? I’m developing a rye IPA recipe where I missed OG and also pre-boil SG, so clearly a mash issue. Im using grain (2 row and rye) from a local maltster regionally grown and found out the kernel size is small (Requires a mill gap .034 or less, I was at .039) so I’m banking on a 2 pass mill at .038 next time hoping it will fix things.

Excellent observation! You may have hit the nail right on the head there.
Those rye kernels are small, even smaller than wheat, which I mill at 0.025" (barley at 0.034"). A common LHBS mill is likely set at 0.045" or even wider. That rye drops right down the gap, mostly uncrushed.

 

[rjhoff]

Yeah, my LHBS confirmed the gap issue, they have two mills with different gaps and also 2-pass on the grain I used. Of course, I was milling my own, unaware.

 

[Vale71]

A gooey mash should be stirred as if it owes you money, and then some. Stirring the mash reduces viscosity, making it more fluid.

Unfortunately the opposite is true with beta-glucans (which is what causes rye beers to be so viscous). Shear forces can cause polymerisation of the glucans and the viscosity can shoot sky-high, even when pumping finished beer.

To the OP: if the only difference between this recipe and other recipes you've brewed with no issues is the rye malt then that is the most likely culprit. High viscosity combined with fewer husk material can lead to severe channelling (as an alternative to a stuck sparge) and loss of extraction efficiency.

 

[Brewbuzzard]

I always hit my mash temp in this system (10 gallon igloo cooler with a false bottom), and I've never had a stuck sparge with rice hulls (knock on wood). Since I started stirring my mash every 15 minutes I've noticed a higher mash efficiency on every beer except this one. However, I've noticed that I'm getting a bit more wort out of the second runnings from the sparge than I should be getting, so maybe I need to dial back the sparge water a bit. But that won't account for missing OG by 20 points! This is the only beer that I'm messing up, and it's also the only beer I brew with this much rye. Maybe that has something to do with it?

The 25% rye is my suspect. Also do you perform a beta glucanase rest and a mash out at 168° or 170°?

 

[thefigure5]

That's doesn't happen. It actually helps releasing them through faster and more thorough hydration.
A gooey mash should be stirred as if it owes you money, and then some. Stirring the mash reduces viscosity, making it more fluid.

I brewed a 50% Rye (malt) beer that took over an hour to lauter 3-4 gallons from, looked like wet cement. Much stirring and adding more hot water helped eventually. The 2 batch sparges were slow too, but got better with time. I forgot to implement a beta-glucanase rest.

STIR LIKE IT OWES YOU MONEY! Great expression, hadn't that, the *like it owes you money* before. I stir practically constantly. I want to make a rye porter next, and the information about grain size and mill setting seems key. I'll have to ask the brew store about doing that. I don't have a mill, yet.

 

[IslandLizard]

I'll have to ask the brew store about doing that. I don't have a mill, yet.

Getting them to reset the mill for you may be the 8th wonder of the world. Let us know how that went.

The 2 LHBS here won't even consider talking about it. Neither would they invest in a 2nd mill if it was just for that purpose...

Going all grain (and buying grain at a group buy) in 2013 the first thing I did was... buy my own mill.

One of our monthly club competition brews is a same-grain/same hop topic. This year it's a crystal (roasted) oat heavy recipe, bought from the one LHBS which supports many of our events and efforts. I questioned the milling part, knowing their wide mill gap and over half our brewers using it without ever looking back.
This was before the COVID epidemic ruined all our plans. So we need to address that again at some later point.

 

[jrgtr42]

When you mentioned the mash at 164, was that the strike water temp or the final mash temp?

 

[thefigure5]

The 2 LHBS here won't even consider talking about it. Neither would they invest in a 2nd mill if it was just for that purpose...

Going all grain (and buying grain at a group buy) in 2013 the first thing I did was... buy my own mill.

I checked here, and the shop does adjust their mill for smaller grain/malt kernels like wheat and rye, maybe six-row also or wheat and rye are six-row? - didn't catch that part. This is lucky. Maybe someday getting a mill will make sense anyway. The few mills I looked at on-line were adjustable, but are some easier to adjust than others?

 

[IslandLizard]

I checked here, and the shop does adjust their mill for smaller grain/malt kernels like wheat and rye, maybe six-row also or wheat and rye are six-row? - didn't catch that part. This is lucky. Maybe someday getting a mill will make sense anyway. The few mills I looked at on-line were adjustable, but are some easier to adjust than others?

Lucky you, and kudos to your brew shop!
Most importantly, you need to evaluate the crush (knowing what to look for) to make sure it works on your mash/lauter system with good efficiency. 80-85% is my target for mash efficiency, and pretty much hit 83% each time. I'm rarely over, sometimes a tad under.

Wheat, rye, oats, 2-row, 6-row (barley) etc., are all different grains and of different size. That's why they should be cracked/crushed/milled according to their size and the mash/lauter system in use.

I've milled Triticale, a wheat/rye hybrid, IIRC. The kernels are smaller than oats. I had the knurls almost touch to mill that to any degree. Then there's millet...

Pretty much all adjustable 2-roller mills are very easy to adjust, same for many 3-roller mills. But some 3-roller mills need to be taken apart to adjust the gap.
I have a 2 roller Monster Mill, the MM2. I adjust the gap about once every brew. 0.034" ("credit card") for barley, then wheat/rye/etc. on a narrower one (0.025"). Or vice versa.

 

[bracconiere]

I've milled Triticale, a wheat/rye hybrid, IIRC. The kernels are smaller than oats.

my JSP wouldn't get tight enough to do oats when i tried a 100% oat malt beer, got piss poor effec, like 65% or something.....20%age points lower then usual....

 

[Mahanoy]

When you mentioned the mash at 164, was that the strike water temp or the final mash temp?

That's the strike water temp - mash temp is 152 for this recipe.

 

[Mahanoy]

Thanks for the insights, y'all! I'm going to look into the milling of the rye because it sounds like that might be the issue here.

 

[Mahanoy]

I just ran this through BeerSmith and if I take out the 4# of rye it ends up with an estimated OG of 1056. My OG was 1052. So I'm pretty sure the rye didn't get crushed in the milling and that's the problem. Looks like it's time to have a chat with my LHBS, or just buy my own mill!

 

[VikeMan]

So I'm pretty sure the rye didn't get crushed in the milling and that's the problem.

It sounds likely. Do you recall how the rye looked when you mashed in?

Looks like it's time to have a chat with my LHBS, or just buy my own mill!

Assuming you have the cash and the space, the latter is always better, because you'll have ultimate control. Another benefit is that you can crush your grains just before mashing. And if you want, you can buy base malts in bulk, which saves money (once you've covered the cost of a mill).

 

[Mahanoy]

All great points! I don't recall how the rye looked, unfortunately, because I wasn't really paying attention to that as a possible issue. I wish I had taken a closer look when I mashed in! But given that taking the rye out of the calculations puts me pretty much exactly where I ended up with the OG, I'm sure that's the culprit. I can't imagine any other reason I'd miss my OG by over 20 points!

 

[Brewbuzzard]

Great detective work