How do I determine my target OG?

I don't really understand those online spreadsheets. I'm going to brew an all-grain brown ale this weekend and this is the recipe I concocted:

7# 6-row US Pale Ale Malt
2# English Amber Malt
.5# English Crystal Malt 50-60
.25# English Crystal Malt 118-123
.25# English Chocolate Malt 450-500

2oz. Northern Brewer Hops
1oz. Willamette Hops
1oz. Columbus Hops

Mash 1 hour at 152

So how do I figure out my target OG and effieciency?

Try this: http://www.tastybrew.com/calculators/

I used this until I purchased beersmith.

Tastybrew has some nice calculators. But, having said that, I'd give a shout out to Beersmith also. Well worth the cash.

http://www.beersmith.com/

Not sure if I'm answering your question, but when you calculate an expected OG from a grain bill, you assume a particular efficiency.

Effectively speaking, there's a certain amount of sugar you're going to extract from each pound of each particular grain type if everything goes right.... if you convert all the starch. If you assumed a 100% efficiency with your mash/lauter, then the calculations would be easy... you'd just add up all the sugar created from conversion of each grain type / amount and determine the OG based on the pre-boil volume of the collected wort.

But you won't hit 100% no matter what you do. So your efficiency is assumed as a certain value and included in the calculations (which is what the spreadsheets / brew programs do).

Once you get more experience, you should be able to accurately know about what efficiency you're capable of hitting. But starting out, you pretty much just have to make an educated guess. Along these lines, if hitting a particular OG is important to you, it's better to assume a low efficiency, as you can always dilute your boil water to hit a lower OG if you're more efficient than assumed. The reverse is not true.

Brewtility.com is my go-to program. It is great and it is free.

1- figure out the extract potential for each of your grains, e.g. for pale 6 row i think it's about 35
2- multiply that number by the number of pounds of that grain you have, so for your pale malt it would be 7 x 35
3- add each of these results together (each grain) and it's your maximum gravity points- the total amount of sugar in your grains. you won't get all of this into your wort.
4- multiply this number by your efficiency
5- divide by your final batch size (in gallons), and that's your estimated gravity

since you don't know your efficiency yet i would just assume something like .70

when you do your first batch, calculate the gravity of the wort you collect and then multiply this number by the volume in gallons you collect. then divide this number by your result from part 3 and you have your efficiency (as a fraction).

Software. I use ProMash. Others use different things. Here's a list of free calculators:

http://www.tastybrew.com/calculators/
http://hbd.org/recipator/
http://www.usermode.org/code.html - QBrew, a free calculator.

According to my copy of ProMash, your grist looks like:

A ProMash Recipe Report

Recipe Specifics
----------------

Batch Size (Gal): 5.00 Wort Size (Gal): 5.00
Total Grain (Lbs): 10.00
Anticipated OG: 1.054 Plato: 13.32
Anticipated SRM: 21.8
Anticipated IBU: 0.0
Brewhouse Efficiency: 75 %
Wort Boil Time: 60 Minutes


Grain/Extract/Sugar

% Amount Name Origin Potential SRM
-----------------------------------------------------------------------------
70.0 7.00 lbs. Pale Malt(6-row) USA 1.036 2
20.0 2.00 lbs. Amber Malt UK 1.037 30
5.0 0.50 lbs. Crystal 55L UK 1.034 55
2.5 0.25 lbs. Crystal 120L UK 1.033 120
2.5 0.25 lbs. Chocolate Malt UK 1.034 475

No hops or anything, because you didn't give enough information.

Cheers,

Bob

Thanks for your help guys! But to summarize, I won't really know what my target OG is until I have a few batches under my belt? I'll keep very good notes!

Not really, no. You'll have to keep good notes in order to determine your brewery's efficiency. Once you do that you'll be able to fairly reliably predict your OG. But keep in mind efficiency is dependent on multiple factors - your efficiency can very easily change.

Best bet is to use your software to establish a ballpark. That's why they set them at 75% as a default! New mashers tend lower, experts higher. While you're learning, your efficiency will be all over the map. Don't sweat it too much.

Cheers!

Bob

ewienclawski said:

Thanks for your help guys! But to summarize, I won't really know what my target OG is until I have a few batches under my belt? I'll keep very good notes!

Click to expand...

That's not exactly the way I'd look at it, but it is one way to approach the problem. What you do know is what OG you expect & want to hit. What you do not know is your efficiency.

With the exception of MAJOR problems with your process that lower efficiency below anything expected, there's no reason you can't hit exactly the OG you wish. All you have to do is calculate your efficiency well-below that expected. Offhand... say 50-60%. More than likely, you'll do better.. in which case your OG will be higher than anticipated. No problem... then you just dilute with water until you get the OG you planned on. The ohly cost will be a bit more grain, but that price should be negligible.

Yes, you could assume a higher efficiency, come up short on OG, and go ahead & make the beer anyway. It will still be beer. But you won't be true to the recipe, and the next time you brew w/ your efficiencies closer to actual, you'll brew a different beer. If that doesn't bother you then no problem. Some people would actually rather the variance because they enjoy surprises. But if you're shooting for consistency (and consistency is necessary in order to provide a background upon which you can judge small changes), then I'd aim to hit my target OG.