OG Question?

[GABrewboy]

My grain bill is:

8 lb. American 2-row
2 lb. American Munich
1 lb. American crystal 40L
5 oz. British Carastan

The OG should have been around 1.056, mine was right around 1.032. What should I do to bring this up next time?

I used 4 gallons for mash in, then 4 gallons to sparge with. I just did a single step.

Thanks

 

[Dude]

Did you correct the temp for your hydro reading?

Are you sure you had a good grain crush?

 

[DeRoux's Broux]

what was your mash temp? did you do a conversion test before you stopped sparging? could be the milling as orrelse implied......

 

[GABrewboy]

Yes, I am pretty sure my mash was crushed pretty good as it was done at the HBS. My mash temp was 158 and held there for 1hr. I did my sparge with a 20 min rest at 170 mash temp. I did adjust the OG for the wort temp.

Hang on.....should my OG be before I boil or after my boil and chill haze? :O This is only my 2nd AG batch, so be nice......"

 

[DeRoux's Broux]

well, sounds like everything should have converted for sure, and probably a good milling ofthe grains. did u have to add water after the racking to primary to get 5 gallons?

 

[El Pistolero]

Hang on.....should my OG be before I boil or after my boil and chill haze? :O This is only my 2nd AG batch, so be nice......"

After you boil...did you take it before?

 

[DJP]

Yes, I am pretty sure my mash was crushed pretty good as it was done at the HBS. My mash temp was 158 and held there for 1hr. I did my sparge with a 20 min rest at 170 mash temp. I did adjust the OG for the wort temp.

Hang on.....should my OG be before I boil or after my boil and chill haze? :O This is only my 2nd AG batch, so be nice......"

After your boil...

 

[Baron von BeeGee]

You can take the reading before or after, but you have to correct for the volume. In fact, I like to take it as soon as the mash is in the kettle but before I boil since I find that's the easiest time to get an accurate volume measurement without having to worry about the various losses (immersion chiller throws off the measurement post-boil). You're probably in pretty good shape if you took that reading with 6-7g pre-boil.

 

[DeRoux's Broux]

i do one pre and post boil. but, the post boil is the main one i worry about for figuring.

 

[Baron von BeeGee]

Yeah, to clarify...I like to get one pre-boil for calculating mash efficiency. I think that's the best time. I like to get one post-boil to see where I wound up with respect to my target for the recipe.

 

[DeRoux's Broux]

Yeah, to clarify...I like to get one pre-boil for calculating mash efficiency. I think that's the best time. I like to get one post-boil to see where I wound up with respect to my target for the recipe.

thanks BeeGee. i shoulda clarified that one too. hell, i missed the whole questiuon about taking a reading pre-boil.....not hittin' on all cylinder's today

 

[Baron von BeeGee]

Me either...couldn't sleep last night, barely dragged into work. Actually looking forward to skipping out early for PT on my ankle and then going to sleep.

 

[GABrewboy]

Okay guys, this reading was pre-boil with about 6-6.5 gal of fresh wort....I forgot to take one after the boil though......dummy me!! I must say it smelled and looked very tasty though......nice carmel color and sweet as a rose smelling.....okay, maybe not a rose, but sure as hell smelled like it's gonna be a nice beer.... Thanks for all the input and help brew buds!!

 

[Denny's Evil Concoctions]

Okay guys, this reading was pre-boil with about 6-6.5 gal of fresh wort....I forgot to take one after the boil though......dummy me!! I must say it smelled and looked very tasty though......nice carmel color and sweet as a rose smelling.....okay, maybe not a rose, but sure as hell smelled like it's gonna be a nice beer.... Thanks for all the input and help brew buds!!

What was your post boil amount of wort. A reduction from 6.5 (@1.032) to 5 gal should leave you with a SG of 1.042

I enetered your ingredients into promash and using a 75% efficiency leaves an est. OG of 1.060 for 5 gal.

What was the temp when you to the Hydrometer reading? I don't trust those hydrometers when they are taken at high temps like 150f etc. Most equipment is more accurate closer to its optimum temp.

 

[GABrewboy]

My post boil is just about 5.5-5.75 gal.....I took the reading at 152 degrees.

Can you by any chance explain efficiency to me? I have tried to find info on exactly what this term means, but have had no luck.

Thanks so much!

 

[Baron von BeeGee]

If you took the reading at 152 degrees your gravity is much, much....much higher than what you read. Most hydrometers are calibrated to 68-70F. Hotter liquid is less dense, so the hydrometer will sink deeper giving a lower reading.

 

[DeRoux's Broux]

My post boil is just about 5.5-5.75 gal.....I took the reading at 152 degrees.

Can you by any chance explain efficiency to me? I have tried to find info on exactly what this term means, but have had no luck.

Thanks so much!

from Prmoash:
The mash efficiency calculator imbedded within Brewing Sessions lets a brewer calculate his actual mash system efficiency based on the predicted volume and gravity vs. a recorded volume and gravity.

it determines the systmes efficiency to extract the desired amount of feremntable sugars for that specific brew session. make sense?

 

[Denny's Evil Concoctions]

What was the hydrometer reading at 152f? (uncorrected temp) I'll double check it for you with promash.

 

[GABrewboy]

My hydro reading at 152 was 1.014.......Thanks

The efficiency definition you gave doesn't make sense to me, but maybe because I am still so new at doing AG batches.

 

[Baron von BeeGee]

Look at efficiency this way...in the grains you put into your mashtun there is a certain amount of sugary goodness waiting to go into your wort. However, in the real world you'll never get 100% of the sugary goodness out of the grains after mashing and sparging. Some of the sugar invariably gets left behind, or perhaps didn't even get converted depending on how well your mash went. What efficiency measures is how much of the sugar you actually got from the grains.

Let's say based on your grain bill that if you extracted 100% of the sugars from the mash you should have an OG of 1.050, but you actually measure 1.040, then your efficiency was 80%. If you measure an OG of 1.030 your efficiency was 60%, and so on.

Most AG recipes assume an efficiency ~70% which most people can achieve with some experience. If you're getting below 70% you should try to figure out where you're losing efficiency and correct it. If I'm around 70-75% efficiency I'm pretty happy. The highest I've gotten is 80%.

 

[GABrewboy]

WOW.....great explanation!! You should be a beer teacher......

Okay, so now my question is: How do you know what your efficiency should be based on the grains you are using and then how do you know if you hit that efficiency? I assume though that you know by the OG reading correct?

 

[ggenovez]

My understanding of the potential exctract (Theoritical maximum efficiency) is that is discovered under perfect laboratory environment, read looking under microscope and counting cells.

Breweries strive for 98% efficiency because any spent grain that still has sugar, makes a huge dent in proffit.

When you LHBS purchases grain, they usualy get a data sheet that has all the information on that grain. It could be specific to that batch of grain or a generic one for their product.

Here is a table http://hbd.org/uchima/tech/extract.html that shows the average depending on grain type.

Here is also another explanation of the process. http://hbd.org/uchima/tech/efficiency.html

Now many things can affect efficiancy including mash temp and sparge design. What kind of a lauter are you using? I had a very poor result when I used a cooler and just used the drain at the end. I figured that eventualy the wort would go through the bed. I had a 30% efficiency on that one. Live and learn.

 

[Baron von BeeGee]

Okay, so now my question is: How do you know what your efficiency should be based on the grains you are using and then how do you know if you hit that efficiency? I assume though that you know by the OG reading correct?

You cheat and buy Promash! At least that's how I do it. You can also use the published potential extract of the grain you are using (as linked in ggenovez's post), calculate what SG it would yield for your volume of wort, and compare it to the SG that you actually measure in your wort. Promash is easier because you just enter your recipe, and the enter your observed SG after lautering.

 

[ggenovez]

Oh, sorry, didnt know we could cheat.

in that case here's a calculator
http://texanbrew.com/tbcalcs/index.php?quicklink=eff



Later

George

 

[pigpen]

I would check ph too.

 

[Nwcw2001]

Through Beer Smith your Hydro correction is 1.034 if your OG was 1.014 @152*

 

[eolle]

My understanding of the potential exctract (Theoritical maximum efficiency) is that is discovered under perfect laboratory environment, read looking under microscope and counting cells.

Breweries strive for 98% efficiency because any spent grain that still has sugar, makes a huge dent in proffit.

You never count cells when calculating theoritical maximum extraction from grain. That is for yeast #s not grain yield.

The following is a generalization there are some differences from lab to lab and assay to assay but the methods are arbout the same. In the lab they will use something similar to what is called a "hammer mill" and pulverize the grain in to a fine powder. There is a very specific water to mass ration added. Then either pure water or a buffered solution is added and allowed to react at optimal temp. This depends on what you are measuring. After reaction you can either centrifuge out or filter out the particulates and measure the amount of sugar. Based on your orignal mass:water ratio you can caclulate theoritical yield. You will NEVER have 100% yeild based on mass from a lab since anwhere from 10-20% (sometimes more) is not starch (i.e hulls, acrospire, proteins ect). Most of the time on a mass basis you will have about 80-85% yeild on a per mass. Now that sets your theoritical maximum yield.

From theoritical maximu yeild we've developed generalizations (lets say 1lb of malt in 1 gal of water will=1.050) so a 50% yield would be 1.025 and a 75% yield would be 1.0375. This is primarly where we get our target gravities using generalizations from maximum theoritical yield (though you can use lot exact figures but its usually not worth it).

BeeGee did a great job explaining this part!

While most breweries will aim for a HIGH yield....Most are in the low 80's% to high 70s. Most of the microbreweries I have seen are happy in the mid to upper 70's for yield. Though with corn or rice you can get a cheaper, higher yield, dryer beer but still not in the 90's as you suggested when properly measured.

Also homebrewers often overestimate (some underestimate but rarely ) yield due to not being able to accurately measure volume...but it doesn't really matter since you are looking for a ball park figure. Kind of fits the old addage..."Never ask a man his salary and a woman her age" (They'll lie)....So I purpose the homebrewer modification "Never ask an all grain homebrewer their efficiency or OG."

-Eric