Consistently missing OG / Need Advice

[Bastido]

So the last few brews I have been doing, according to BeerSmith, I have been missing my OG by around 10 points every time. Ten points on the low end.

I realized the first few times, maybe I didn't use enough sparge water, but this last time, I used quite a bit, and boiled for over two hours and still missed my OG by ten points. Here is the last recipe.

Double Dead Guy Clone
American Barleywine


Type: All Grain
Date: 1/26/2010
Batch Size: 5.00 gal
Brewer: Bastido
Boil Size: 6.84 gal Asst Brewer:
Boil Time: 90 min Equipment: Brew Pot (7.5 gal) and Igloo Cooler (10 Gal)
Taste Rating(out of 50): 35.0 Brewhouse Efficiency: 75.00
Taste Notes:

Ingredients

Amount Item Type % or IBU
11.00 lb Pale Malt (2 Row) US (2.0 SRM) Grain 64.71 %
4.00 lb Munich Malt (9.0 SRM) Grain 23.53 %
1.00 lb Caramel/Crystal Malt - 10L (10.0 SRM) Grain 5.88 %
1.00 lb Caramel/Crystal Malt - 20L (20.0 SRM) Grain 5.88 %
1.00 oz Cascade [5.50 %] (90 min) Hops 16.3 IBU
2.00 oz Cascade [5.50 %] (60 min) Hops 30.4 IBU
1.50 oz Cascade [5.50 %] (20 min) Hops 13.8 IBU
1.00 tbsp PH 5.2 Stabilizer (Mash 60.0 min) Misc
1.00 items Whirlfloc Tablet (Boil 15.0 min) Misc
1.00 tsp Yeast Nutrient (Primary 3.0 days) Misc
1 Pkgs Pacman (Wyeast Labs #1764) Yeast-Ale


Any help would be appreciate. I'm mashing in a ten gallon cooler. 7.5 brewpot, I've been collecting the extra runnings in my old 4 gallon brewpot and letting it boil down on the stove while I boil the rest on my burner.


Est Original Gravity: 1.092 SG
Measured Original Gravity: 1.082 SG

 

[brettg20]

You are taking a reading after the boil right before you ferment right?

 

[Bastido]

Yes, of course!

 

[EBloom97]

Well, your recipe is dialed in for 75% efficiency, which you obviously aren't getting. You can up your grain bill to compensate, or try to bring your efficiency up.

 

[Bastido]

That's what I'm trying to figure out, why my efficiency is so low. Should I be hitting those numbers with this amount of grain??

 

[wonderbread23]

Your strike water should be in the 4-5 gallon range for that much grain. Since you are only collecting 6.84 gallons total, that is leaving very little sparge water. With that much grain, you'll need to be at 8+ gallons preboil if you hope to get 75% efficiency. I'd mash at 1qt/lb (since it is a big beer) and then sparge with 4-5 gallons. That should get you where you need to be.

 

[EBloom97]

1.082 is about 66% efficiency. It's not great, but as long as you can make a reasonable prediction about your efficiency, you should be able to scale your recipes appropriately. If you want to focus on upping your efficiency, you should be looking at things like the quality of your crush, how good of a conversion you're getting, how well you're hitting your temperatures, etc.

 

[dragon99]

I'm with EBloom97. Basically you just need to lower you expectations. If your consistently missing your OG, then 75% eff isn't what you should be basing your recipe on.

The next question you have to ask is if you are OK with a lower efficiency? Personally I rarely get better than 70%eff and I'm perfectly happy.

 

[Bastido]

You guys are probably right. I'll try and tweak a few things, but in the end I'll just have to throw a couple more pounds of base malt in there. And yes Dragon, I'm perfectly happy with my beer!!! This is just one of those things I obsess over, you know how it goes!


Thanks for the help!

 

[TheMan]

I agree with the above...you have two choices. Try to improve your efficiency, or leave everything as is and just accept that you consistently get 66% efficiency and brew consistently every time. Low efficiency doesn't mean you are a bad brewer.

 

[Shooter]

Low efficiency doesn't mean you are a bad brewer.

Now I KNOW this can't be true.

Are you trying to say that my efficiency might be based on my setup and other factors and is not a reflection of my value as a human being?!?!?

 

[user 22118]

I consistently get between 70% and 75%. I just input my efficiency as 70% and then hit my numbers spot on. Occasionally I will end up slightly above and have a little more potent beer that still tastes great. Don't chase efficiency though, it will shave like $5 off a batch at the max. Plus, when making a bigger beer you will find that your efficiency will drop the bigger you go. I aimed for a 1.120 beer and got 1.105. Less than I wanted, but still an effing great beer at whatever...60%-65%... efficiency it is.

 

[Ohio-Ed]

I think a problem most home brewers have with determining OG is measuring the final volume. The difference between your expected OG (1.092) and your measured OG (1.082) is 11%. 11% of the volume of your 5 gallon batch is just over 2 quarts (not that much if you think about it).
How did you measure your final volume? If you used the lines on a fermenting bucket, they are notoriously inaccurate.
And even if you got all the sugar into the boil kettle, did you get it all out (any losses to trub, chiller, etc?).
Did you compensate for wort temperature with the hydrometer?

 

[Undead8]

Before, I couldn't get over 60-65% efficiency. Sometimes I would even have around 50%.

So I bought a mill and crushed my barley myself (instead of crushing it at the store). Now I always get over 75%.

 

[Bastido]

I'm pretty sure I ended up with a little over 5 gallons, so I must not have boiled it long enough, still 10 points would have given me a lot longer boil, and less final volume. Yes was a little trub in the bottom of the kettle, around a quart. Yes I adjusted for the wort temperature, in the hydrometer.

I haven't changed the setting on my grain crusher since I ordered. I just used the default crush.

Also, I just read the newest article in BYO about an all grain brew day. I have been doing all grain for a while but I wanted to see how my system stacks up to what they were doing. One thing that caught my attention was, they say to drain the first runnings at a rate that would take about an hour or more, before I batch sparge. Is this true?? I just vorlauf, and open the valve all the way to collect the first and second runnings. Is this ok??

 

[BillyBeer]

Well that is how I batch sparge - open it up full bore and vorlauf for 2 to 3 gallons then collect runnings. I normally get between 80 and 85%. I have tried several SS braids and CPVC manifolds and found that they changed my eff. almost more than crushing my own grain.

I agree with the others don't sweat it but I understand the obsession - I bet we all do

 

[AiredAle]

The drainage rate for first runnings of a batch sparge will have no effect on efficiency, as long as you get the same volume of wort out of the MLT. Slow draining will allow a little more wort to trickle out of the grain bed than fast draining, but the difference is pretty small.

The whole point about batch sparging is an increase in speed with a small sacrifice of efficiency. Why would the author of that article recommend slowing the process down? Does (s)he explain the reasoning?

 

[Bizoune]

If your using software on brew day, simply enter your anticipated efficency when you're getting your recipe together. After you've sparged, get your gravity reading. Then, play around with your efficency number in the software until your pre-boil gravity is exactly what you've measured with your hydrometer. Your post boil gravity projection, will change in function of this. Then you can go ahead and adjust your hop schedule to get all of your numbers.
At the end of the boil, if your volumes are calculated correctly, you should be on the money
I find that this approach helps getting consistent balance in my brews. When my efficency is all over the board from batch to batch, especially when I'm trying out new equipment, at least it gives me the opportunity to adjust hopping rates. I might not always get my 6.5% IPA that I was anticipating but at least I'm able to get a final product that's properly balanced.

Brewtarget as well as Brew Pal for iPhone are software that I use regularly.