Consistent low OG, tried "everything"

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maho

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This is a long post as I want to give you as much info as possible.

I have just brewed my third all grain batch and all three have had low OG by app. 10-15. (Batch#1 Meas:1035 vs. Recipe:1045, Batch#2 Meas:1038 vs. Recipe:1050, Batch#3 Meas:1045 vs. Recipe:1060). My software tells me I only have 55-60% mash effectivity (ProMash)....

All grains have been crushed by the store where I bought the grains.
I am (for batch #2 and #3) using PH5.2 so PH should not be a problem.
My mash temperature is right on the money (150-155), checked by two thermometers (analog & digital, app. 6F difference between them, so I take the average and aim for 152F)
Gravity is checked by hydrometer and temperature adjusted, usually at around 100F.

Here is the flow: (5-6Gal batch)
1. 5 Gal mashwater is heated to 175F
2. Added to the grains in the mashtun (10Gal round Cooler w. domed steel falsebottom)
3. Added 1tbsp. PH5.2, stirred and temperature adjusted
4. Usually I stirr at the 30min mark as well
5. I heat app. 4 gal og sparge water to 175F
6. After 60 mins, recirculation, I then add the spargewater 1-2qt at the time and try not to disturb the mash. I usually keep at least 2-3 inches of water over the grains. I even have tasted the grains to taste if there is any sugar left, but they do not taste sweet at all after the mashout.

All my brews have been low, but fermentation i lively and the beer taste is great. I have checked the hydrometer w. regular water and with a 1050 suger solution and it looks ok.

I have read several books and searched forums to find a solution. Only thing I can think of right now is to try batch sparging instead of flysparging.

If anybody has an idea what to try I would much appreciate it.

Thanks
Hommel HomeBrew
 
Most people I have read experience a nice jump in efficiency by grinding their own grain. I know my crush is finer than a homebrew shop crush. Look into a Barley Crusher or some kind of mill that will crack the grain without shredding the husks.
 
water or crush. If you LHBS is like mine, they crush a lot less fine because they want u to buy more grain
 
Any chance you could post a nice close-up photo of your crushed grain? I am betting it is a really coarse crush that is the cause of your troubles.
 
1. 5 Gal mashwater is heated to 175F

Why so high on the strike water? I heat mine up to 12-14F higher than my mash temp. By the time I transfer and the insulation in the cooler heats up I'm 9-10F above my mash temp and I dough-in.

I'm not suggesting that this is a source for the issue that you brought up, it just stood out to me when I read your post. As others have already suggested, the first place that I would look is the crush.
 
What jumped out at me is the method you're using to follow a desired mash temp. Averaging two inaccurate thermometers isn't going to get you the temperature you desire. Calibrate your thermometers in ice water, and see if either are accurate. For decent results with AG brewing, a good accurate thermometer is a necessity.
 
Thanks for all the suggestions.

The grains I have been using have been:
Batch#1: Bumber Blond from Mountain HomeBrew, Kirkland WA. Was also crushed here
Batch#2: HefeWeizen from MoreBeer, came crushed as well
Batch#3: Selfmade Pale Ale recipe w. 12lbs of grain, bought and crushed in Mountain HomeBrew

My water is filtered tapwater (Culligan D-20 filter). Can it be low calcium? Bare in mind that I am adding ph5.2 from MoreBeer.

I usually hit the mash temp quite well. Usually I am a bit hot, and I add cold water to get the temp down. I try to use at least 60mins for the mashout.

My analog thermometer will not go to 32F in ice water or 212F in boiling water so it is hard to calibrate. It is a cheap thermometer from MoreBeer. I have a digital (sugar thermometer, for making candy) which seams quite accurate in ice water and boiling water, but of course it does not say anything about the 150F accuracy.

My thinking is that if the mash is too hot, I should get ok OG, but end up with a sweet low alc. beer due to the dextrins. But my beer is not sweet and ferments well. So thinking that it might be too cold instead I have tried to hit the higher end of the mashtemp (152-155).

Please keep the suggestions coming! Again thanks to all for their contributions!
 
First, your thermometers differ by 6 degrees. Find out which is wrong, and don't use it, replace the batteries, or recalibrate it. A thermometer in iced water should read 32. Boiling water at sea level should read 212 - subtract 1 degree F for every 500 feet above sea level.
Second, how long do you take to sparge? As Bobby said, you need about 60 minutes or greater for fly sparging.
Third, You either have a mash problem, or a sparge problem (or both). You could use an iodine test to check for incomplete conversion in the mash. To check your sparge efficiency, after you have finished, give the sparge a good stir and wait for 10 minutes. (You may have to add some extra sparge water if your grain bed is very stiff), Then drain enough from the grain bed to take a gravity check. If the gravity of these runnings (after cooling) is much above 1.010, then you have a sparging problem (probably channeling as a result of sparging too fast).

-a.
 
Your process sounds pretty sound. I am surprised your efficiency is so low. I assume your reported efficiency is brewhouse efficiency?

Have you computed your extraction efficiency and lautering efficiency separately? That might be a big help. If it is not your crush, I am now wondering if you have a lot of deadspace or other wort loss in your system that is dragging your efficiency down.
 
my gravity is measured when cooling the final wort. So it is the gravity at the beginning of fermentation. I have a scale on my fermenter, so I know how much wort I have.

My method is from a brew course I took. There we had 80% efficiency, so I am also puzzled that this does work with my equipment.

I do check my gravity at the start and end the lautering, and stop around 1010. My gravity at the begining of lautering is usually not above 1055 (which makes it hard to make a 1060 work ;-).

As I said I usually try to go for min. 60mins for sparging/lauertering/mashout.

I have just spend the last half hour looking at grain mills.... Now to persuade the wife... Could be nice to have though....

Thanks!
Hommel HomeBrew
 
All I can say is I'm right there with you, It seems my efficiency has been going lower and lower.
Good luck and I hope you get it nailed down.
 
How long do you take to run the sparge water through? 60 minutes? I'd give batch sparging a go anyway because anything is better than 60%.

+1 on trying batch sparging. I'm not sure your flysparge setup, but if you get any channeling then your efficiency suffers.

I do Bobby_M's method of 'No Mash Out Double Sparge', and my last efficiency was 77% I'm a newbie All Grain guy, so I'd say his method is almost fail-safe. I use the SS Braid method.

Without a good flysparge setup, I feel like you're shooting yourself in the foot.
 
My water is filtered tapwater (Culligan D-20 filter). Can it be low calcium? Bare in mind that I am adding ph5.2 from MoreBeer.

One suggestion, though it most likely isn't your problem, you can't just add 5.2 and expect everything to be fine. If you don't know what your water profile is, you're possibly not getting what you're expecting from the 5.2. 5.2, although great, doesn't work when you're water is outside the 5.2's buffering capabilities (ex, high temporary hardness or high in residual alkalinity). You'd still have to treat it a little (dilute with DI) to ensure the 5.2 will work properly. But again, that most likely isn't your problem.

I'd suggest double grinding your grains. I double grind everything at my LHBS. Even if i buy something pre-ground from them, i grind it a second time, and haven't fallen below 75% since (started in the low-mid 60's).
 
My setup s simple. A turkey fryer pot/cooker and a 10 gal round cooler with dome false bottom. Fly sparging is done by hand, but beeing careful not to disturb the mash (I pour the water onto a spoon at the water surface. Looking at the grain bed afterwards there are not signs of channeling.

My last batch was 12lbs of grain, and my collected wort was app. 6gals.

As for the water our water is very soft (Kirkland, WA), so I don't think this is the problem.

I will look into Bobby_M's sparging method, and possibly invest more dough in a grainmill.

Thanks All! I will keep you updated on my next batch.
 
You said you see a gravity of about 1.010 towards the end of your sparge. Good. One way to test if you're getting channeling:

After you get all your preboil runnings. Throw an extra gallon of hot water into the mash, stir it up like crazy and run off a sample. Take the gravity reading now. If you've got something higher than 1.020(ish) you know that you channeled like a mofo.
 
The first thing that jumps out to me is that the fly sparging process should take about 60min with the proper flow. If you do that by hand, it strikes me that you wouldn't be getting the proper sparge action, but you are much more patient than i would be, and if you're hitting a final running grav of 1.010 it sounds like that shouldn't be the problem. I think batch sparging will eliminate at least that portion of the equation, to narrow down your problem.
 
Well, yes and no. By the time the grain and cooler walls get in contact with the water, the temp will be pulled down under 160F pretty quickly. It's the same reason why we can batch sparge with 185F infusions... the temp equilizes in the safe zone quickly.
 
175 definitely seems too high for a strike temp. I usually do 168 for a mash temp of 153. Are you preheating your mash tun?

I would strongly suggest trying the no mashout double batch sparge technique, and buying a high quality thermometer that you can calibrate. I get 75-80% brewhouse efficiency with that technique using my LHBS milled grains.

Don't be afraid to sparge hot. Like 180 or so. Sugar dissolves more readily in hot water, and 180-185 still isn't nearly hot enough to start worrying about tannins from the grain husks. I got a good 7% bump on average when I raised my sparge temp from 175 to 185.
 
Thanks, this is yet again another good thread dealing with us NOOB's trying to our process nailed down.
 
Well, yes and no. By the time the grain and cooler walls get in contact with the water, the temp will be pulled down under 160F pretty quickly. It's the same reason why we can batch sparge with 185F infusions... the temp equilizes in the safe zone quickly.

I'll never challenge BobbyM -- he's the man.

So is 170F indeed the temp that kills enzymes?
 
OK, My "conclusion" on all this is:

1. Get a mill, I have decided on the Barley Crusher. It is ok pricewise and PnC (Plug n' Crush) out of the box.
2. Use Bobby_M's NMODBS technique, thanks for an excellent website Bobby!
3. Get a better thermometer. Anybody got a recommandation for a good one. I like the old fashioned analog ones best.

I will post my findings from my next batch, look for updates in this thread in 4 weeks time. Thanks to everyone that contributed!
 
OK, My "conclusion" on all this is:

1. Get a mill, I have decided on the Barley Crusher. It is ok pricewise and PnC (Plug n' Crush) out of the box.
2. Use Bobby_M's NMODBS technique, thanks for an excellent website Bobby!
3. Get a better thermometer. Anybody got a recommandation for a good one. I like the old fashioned analog ones best.

I will post my findings from my next batch, look for updates in this thread in 4 weeks time. Thanks to everyone that contributed!

I'd just get a cheap floater from your LHBS-- they always seem to be pretty damn close and will be helpful for getting your efficiency respectable.
 
So I promised you guys an update..

This weekend I brewed a ESB. I used my new Barley Crusher (default setting) and Bobby_M's NMODBS technique, and .....

I get app. 70% efficiency. It is not 80% but its not 55-60% either.
I am happy, there are still a lot of tweaks I can try

Thanks to everybody that contributed!

Hommel HomeBrew
 
This thread is great! I have the exact problem as OP. 3 all-grains now 1st one was Ed's Haus ale, efficiency was great! hit my OG etc...No ph5.2 just bottled spring water (arrowhead I think). second and third I used ph5.2 with different spring water(crystal gyser and another which I dont know the name of. My efficiency was at 60% or less and I missed my OG by 10-15 points. I fly sparge but have 2 rubbermaid coolers and use a rotating sparge arm (althouh in order to get the time out of it I want, it runs too slow to rotate). I guess lessons learned are to mill my own grain. (first was from midwest, second a LHBS, third a different LHBS (at ballast point brewery where they wen tot back and used their crusher for me so the crush was very good). I will also invest in a floating thermometer cause my digital one takes a very long time to settle in on a temp. Other than that, I'll keep working on everything and hope for the best. I think I'll stop using the 5.2 though and try to get an analysis of my local water.
 
I have been having a very similar problem as well. Some of that improved with a finer crush. Up to 70%. I use beersmith, and adjusted my brewhouse effeciency from the 75% default to 62% which was what I've been running prior. It adjusts how much more grain you need to hit your OG. Doesn't help find why your efficiency is low but corrects for it. I was dead on my last batch. An extra 1-2 pounds of 2-row was all I needed. Still working on the perfect crush.
 
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