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Good efficiency but low OG

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tempestam83

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So I brewed a 3-gallon IPA yesterday and got 76% efficiency which I was super excited about because that's highest I've gotten thus far.

However, at the end of my boil my OG was low. I use Brewer's Friend for all my brewing and with this recipe I was supposed to be at 1.073 but only came in at 1.06.

Grain bill is as follows:

8 lb American - Pale 2-Row 37 88.9%
4 oz American - Caramel 60L 2.8%
4 oz Flaked Wheat 2.8%
4 oz German - Melanoidin 2.8%
4 oz Canadian - Honey Malt 2.8%

I did a 70 min. 6 gallon mash at 150. Took out the bag, brought temp up to 170 for a 10 minute mashout with lots of stirring and squeezing at the end.

After a 70 min. boil I had about 4.5 gallons left and gravity at 1.060

Any thoughts?
 
What did you put as your expected efficiency? Can you do that in Brewers Friend? I know you can in beer smith, but b I expect that your projected efficiency in the program didn't match what you actually got. The two aren't necessarily related. I could have crappy efficiency and still wind up with a high OG, depending on my grain bill.

If I was at my PC I'd plug your recipe into BS and see what it says. Maybe I can get to it later
 
What did you put as your expected efficiency? Can you do that in Brewers Friend? I know you can in beer smith, but b I expect that your projected efficiency in the program didn't match what you actually got. The two aren't necessarily related. I could have crappy efficiency and still wind up with a high OG, depending on my grain bill.

If I was at my PC I'd plug your recipe into BS and see what it says. Maybe I can get to it later


You can edit your efficiency which I did. With 77% is should have been at 1.072. My guess is I must have miscalculated?
 
You have 50% too much volume after your boil. That is why the OG is low. Your brewhouse efficiency (assuming 36 PPG) in the grain bill is

270/324 x100

=83% BH efficiency assuming volume in the FV is 4.5 gallons and your 1.060 OG is measured correctly.

Recipe is for 3G. You collected 4.5 gallons.

Nothing more complicated than that. A 50% error in your volume.

More on efficiency and how to calculate it below in my sig.
 
Based on your grain bill and actual volumes, my simulator predicts an OG of 1.059, which is pretty close to what you measured. I think you got more volume than intended, so the OG has to come out lower.

Edit: I see Gavin beat me to the correct reply. Just for completeness, I also calculate your mash efficiency at 83%.

Brew on :mug:
 
Thanks guys. So should I start with 5 gallons then? With six gallons, I usually end up with 3.5 into the fermenter with 3 gallons of finished beer.
 
Thanks guys. So should I start with 5 gallons then? With six gallons, I usually end up with 3.5 into the fermenter with 3 gallons of finished beer.

The best thing that you can do is mimic your same process over and over again. To say that you should start with only 5 as opposed to 6 is not an accurate method.

Accounting for hops, grain, and boil off will determine your fermenter volume.

What else was different this time? Less grain? Less hops? Less boil off? It should be one of those 3 things.
 
If you're doing full volume mash then you need to take into consideration how many #'s of grain you will be using, how many ounces of hops you'll be using, boil off , and if you're dumping all the wort into the fermenter or leaving the break material behind. When you have all of those numbers in place then you will be able to determine what your starting volume needs to be. Each batch will be different if it's a different beer. (Grain bill, hops, etc..)
Take notes, read up on grain and hop absorption rates, and know your systems boil off rate and you should be able to hit your final volume. Now you'll have to adjust how much water you use down the road when you have a solid process and know what your average efficiency because you can then use more or less malt to get a desired OG but for now I suggest you find what works for your system.
Hope this helps out
Edit: @brewprint beat me to it
 
Thanks for all the input. I start with 6 gallons and usually wind up with 3.5 gallons in the fermenter. I leave all the trub in the kettle and by the time I bottle I have 3 gallons.
 
Thanks for all the input. I start with 6 gallons and usually wind up with 3.5 gallons in the fermenter. I leave all the trub in the kettle and by the time I bottle I have 3 gallons.


You can't do that for every batch of beer you make and expect to come out the same 3.5gal every time.
Take the time to learn a little bit about the variables to consider and apply it. I understand that this is a hobby and we all want to make good beer but we have to take a bit of a scientific approach to it instead of winging it. By knowing what the outcome should be instead of hoping for a particular outcome it makes it so much more rewarding. Nothing quite like designing a recipe, hitting all the numbers and sitting down with a glass of said beer that tastes just like you planned. At least that's how I feel.
I'm not trying to be a A-hole. I am just trying to encourage you to do your homework and enjoy the fruits of your labor. Cheers![emoji482]
 
I'm trying I'm trying believe me. I'm mostly sticking with IPAs right now. Generally 8 pounds 2 row with a pound of various adjuncts or specialty grains. I just got a 10 gallon MegaPot a few weeks ago so my process has changed a lot from using my 5 gallon kettle.

The thing I love about this is I just want to keep brewing until I get it right. And then keep brewing.
 
Calculate your water volumes yourself to the point that you understand what they mean. You'll find a) what you want to use in terms of mash thickness, b) what your value is for water absorption by the grain, and c) your boil-off rate. Here's an example of my calculations (note - I have a bottom-draining mash tun so I don't factor in any dead space / volume left in the mash tun. Most people have some amount of liquid that remains in the mash tun after draining, so you'd have to figure out what that is as well).

waterCalcs.PNG
 
There's no way that you're going to have any consistency without some kind of calculator unless you're doing the exact same hop, grain, and water volume to start.

I recommend this one:

http://pricelessbrewing.github.io/BiabCalc/

Put all the information from a batch that you've already done and see how it lines up. Then you should be good to go.
 
Brewer's Friend also has a water calculator built in for every recipe - check under the Recipe Tools tab. You do need to set your equipment profile (under My Profile from the My Brewing tab).
 
All the above on tracking your volume losses and equipment profile. I have even gone so far as to make a reference mark on my burner regulator so I know how far open it is (like hi, med, low on cook top).
Going from the 5 gal to the 10 gal has thrown off all of your expected losses you were used to.
 
Thanks everyone for all your help. Think I've got this thing figured out. Was using way too much water to start.

According to brewer's friend and priceless brewing, I'm going to need just a little over 5 gallons total for an IPA with 8 lb grain and 6 oz total hops for a 3 gallon batch.

Very excited to brew again.
 
Thanks everyone for all your help. Think I've got this thing figured out. Was using way too much water to start.

According to brewer's friend and priceless brewing, I'm going to need just a little over 5 gallons total for an IPA with 8 lb grain and 6 oz total hops for a 3 gallon batch.

Very excited to brew again.

Those calculators may not be perfect for your system either. I've had to make adjustments with mine but they get you a good starting place. Just don't forget the change the numbers withe more or less grain and hops because that changes everything.
 
For efficiency the best thing is to accurately measure cold wort volume and gravity just prior to pitching.
 
Those calculators may not be perfect for your system either. I've had to make adjustments with mine but they get you a good starting place. Just don't forget the change the numbers withe more or less grain and hops because that changes everything.

I agree that Priceless is awesome but you *WILL* have to adjust your absorption rates and boil off rates for *YOUR* setup.

Possibly several times. Iteratively. Repetition is the key. Then you'll make a small change like getting some whole hops from a friend and it will make you off by a quart. But that's not important here. Keep records, keep updating, and pretty soon after 2-3 batches, it will poot out the numbers that match your results.
 
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