I'm screwed...

I'm having issues figuring out exactly when and how to use my hydrometer. I thought readings were to be taken from the carboy right before the yeast is pitched, when racking into secondary, and before bottling/kegging. I've been reading the board though and it seems like many people take readings during the mash and before the boil as well, and I'm confused about exactly which is supposed to be OG and FG and I'm just confused in general. My latest attempt was Bobby's All American Amber listed in the recipe database. The OG is supposed to be 1.052. The reading I took right before I pitched the yeast was 1.035. However, the hydrometer predicted a little under 5%abv which is what it should be in according to the recipe. Did I screw up the beer or not take an OG reading at the apropriate time?

Are you an AG brewer, or extract?

Start here:

https://www.homebrewtalk.com/wiki/index.php/Hydrometer

and here:

www.howtobrew.com

Great references for a confused brewer.

All Grain.

Sorry, I gave you some references when your question was a little more specific than I first thought.

OG is Original Gravity - the hydrometer reading after the boil and before pitching yeast

FG is Final Gravity - the reading after fermentation is complete (usually taken just before bottling, but beer in the bottle/keg should net the same result)

The reason people take pre-boil readings is to determine efficiency and/or to calculate the sparge more accurately.

If you are brewing all grain without this fundamental knowledge (and if you're missing your target OG by 17 points), I might suggest a bit more research and reading before your next batch.

I just got crappy efficiency then?

bobwantbeer said:

I just got crappy efficiency then?

Click to expand...

Indeed you did. Really crappy efficiency. Probably less than 50%.

What's the best way to learn how to calculate and achieve proper efficiency?

I need to learn how to calculate and achieve proper efficiency fast, because my last brew seems to have been a big waste of time.

Well, yeah, it sounds like it if your hydrometer was reading 1.035 and you were expecting 1.052.

BUT, and this is what I do, I know that my efficiency is crappy. So, I just use more grain! And remember, whatever recipe you used is based on the recipe creator's efficiency. So, say I'm making Yuri's recipe and he gets 85% efficiency for an og of 1.050 (just an example!), using 8 pounds base malt. When I make that same exact recipe with my 68% efficiency (at best), my og will be 1.040. Since I know that before I start, I adjust my recipe to use 10 pounds base malt. So, you can find out what your normal efficiency is, and still create any recipe and any og.

Another thing you said- your hydrometer read 1.035 or 5% alcohol. That's not quite accurate. If you were making wine, yes, since it would ferment back to .990.

But that 5% is potential alcohol, not the true amount to expect in your beer. For a true ABV reading, the formula is (OG-FG) x .131. Beer always has unfermentables in it, and should never get below around 1.008 or so. So, if it was 1.035, and it finished at 1.010, the formula would be (35-10) x .131 = 3.28 ABV. A nice session beer!

So the answer to your questions is pretty complex, as you can see! The short answer is to take your sg when you get ready to pitch the yeast, and at the end of fermentation. The hydrometer is useful, though, for checking the runnings of your sparge as well as determining your pre-boil gravity.

That sucks. Please post more information on your recipe, process and what you think is wrong with your brew. Someone will be able to help.

It's easiest to calculate your efficiency through brewing software. I'm not a math whiz, so that's what I do.

I'm sure that others can chime in and give you the formulas, but I've seen them and they're a little too complicated for my small breain.

I read about your problems. Please try to keep them all in the same thread where applicable. But it's all good.

If you want to rescue your batch, boil up about 2 lbs of dry malt extract with a quart or so of water. Cool it, then toss it in your fermenter. It'll get your recipe back about where you wanted it.

Or, in the alternative, just relax and enjoy the beer you've made.

As for lousy efficiency, tell us more about your process. Do you mill your own grain? Where did you get it crushed? How do you mash? Cooler? More details please.

so I don't necessarily need to dump this brew? I still have a variety of questions, so I'm taking this one to the AG forum.

http://www.howtobrew.com/section2/chapter12-5.html
Do the math once, then get some software.

YooperBrew said:

It's easiest to calculate your efficiency through brewing software. I'm not a math whiz, so that's what I do.

I'm sure that others can chime in and give you the formulas, but I've seen them and they're a little too complicated for my small breain.

Click to expand...

What's a formula?

bobwantbeer said:

so I don't necessarily need to dump this brew? I still have a variety of questions, so I'm taking this one to the AG forum.

Click to expand...

Absolutely not! Don't dump it! It's still beer, and might be a good one at that! It might be lower in ABV than you planned, but it'll still beat Bud any day!

bobwantbeer said:

What's a formula?

Click to expand...

See the link in the post just above from Beerific.

The recipe was from the forum database. It's Bobby's All American Amber. Typically I get my grain milled at the local brew pub, but last night I used a hand mill and the brew store to save myself a trip. I mashed into my 10 gallon igloo at 154 degrees for 60 minutes. I may have caused myself a problem by trying a decoction even though the recipe didn't call for it. I was curious and haven't tried it yet and thought what the hell. I was shooting for about 7 gallons of wort and got about 6.5. After the boil I was at about 5 gallons, and I was shooting for 5.5 so I topped it off with a few more quarts of water. I rocked the carboy a few times to stir it in before taking a reading, in the future it will probably be more sensible to top it off in the kettle before I poor it in the carboy. I took a reading and got 1.035 and I was looking for 1.050, so I fell well short. That's all I can think of for now. Thanks. And sorry about switching threads this is my first forum of any kind, and I don't know the etiquette.(or how to spell etiquette most likely)



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Default Bobby's All American Amber
Recipe Type: All Grain
Yeast: WLP001
Batch Size (Gallons): 10
Original Gravity: 1.052
Final Gravity: 1.014
IBU: 32
Boiling Time (Minutes): 70
Color: 13
Primary Fermentation (# of Days & Temp): 7 days @ 65F
Secondary Fermentation (# of Days & Temp): 18 days @65F
Additional Fermentation: none

Bobby's All American Amber
10-B American Amber Ale

Size: 10.5 gal
Efficiency: 78.0%
Attenuation: 72.9%
Calories: 172.45 per 12.0 fl oz

Original Gravity: 1.052 (1.045 - 1.060)
Terminal Gravity: 1.014 (1.010 - 1.015)
Color: 12.7 (10.0 - 17.0)
Alcohol: 4.94% (4.5% - 6.0%)
Bitterness: 32.29 (25.0 - 40.0)

Ingredients:
16 lbs 2-Row Brewers Malt
1 lbs 2-Row Caramel Malt 80L
.5 lbs Carared®
1.5 lbs Melanoidin Malt
1 lbs Vienna Malt
1 oz Amarillo (8.5%) - added during boil, boiled 70 min
1 oz Cascade (5.5%) - added during boil, boiled 40.0 min
1 oz Cascade (5.5%) - added during boil, boiled 15 min
2 oz Northern Brewer (8.0%) - steeped after boil
1 ea White Labs WLP001 California Ale

Schedule:
Ambient Air: 70.0 °F
Source Water: 60.0 °F
Elevation: 0.0 m

Mash In - Target: 154 °F
Sac Rest - Rest: 60 min; Final: 153.2 °F

I just have no understanding of them beyond that. I gave up on math sophemore year. If only I had known I'd be homebrewing!

much appreciated

Ah, I'm the same way. Well, you can download a free trial of Beersmith, or there are some free programs out there, and that really helps alot!

Or, if you post your recipe, I can run it through mine and give you your efficiency.

Ok, to give you an idea of your efficiency, I ran that recipe in Beersmith, cutting it in half for a 5 gallon batch. At 1.035, you got a bit under 50% efficiency.

I'm not sure exactly why it's so low- so could you briefly run through your procedures (like how much water you mashed in with, how much you sparged with, and what those grains looked like when you milled them. I'm sure we can help you improve this.

YooperBrew said:

Ok, to give you an idea of your efficiency, I ran that recipe in Beersmith, cutting it in half for a 5 gallon batch. At 1.035, you got a bit under 50% efficiency.

I'm not sure exactly why it's so low- so could you briefly run through your procedures (like how much water you mashed in with, how much you sparged with, and what those grains looked like when you milled them. I'm sure we can help you improve this.

Click to expand...

I mashed in with six gallons at 154 and batch sparged with 2 gallons at 170. Most of the grain I bought pre milled. The vienna, munich, and extra munich I used to sub for the melanoidin which the store didn't carry were milled there. The crush seemed ok to me(me being extremely novice), It wasn't too floury, and it didn't seem under crushed either. Am I supposed to mash in at a higher temperature to achieve 154 once it gets in the MLT? Because I just heated the water right to 154 and threw it in the sucker.

Bob, you are learning.

No one has yet asked, so I will:

What was the temperature of the wort for which you measured an sg of 1.035?

sg= any old specific gravity
OG and FG have already been covered in this thread.

It took a little longer to chill because my heat exchange isn't the most efficient. It got down to about 79 degrees and I put it in the fermentor, added a little bit of tap, and took my reading. Truthfully I didn't take a temp of the sample. I'm guessing somewhere between 75 and 79 degrees.

bobwantbeer said:

I mashed in with six gallons at 154 and batch sparged with 2 gallons at 170. Most of the grain I bought pre milled. The vienna, munich, and extra munich I used to sub for the melanoidin which the store didn't carry were milled there. The crush seemed ok to me(me being extremely novice), It wasn't too floury, and it didn't seem under crushed either. Am I supposed to mash in at a higher temperature to achieve 154 once it gets in the MLT? Because I just heated the water right to 154 and threw it in the sucker.

Click to expand...

Yeah the temp should be 154F when the water and the grain are mixed (well) together.

Here is a simple web calculator that might help: http://www.krotchrott.com/calc.html

I think you also need to sparge with a larger volume of water. If you haven't already you might give How to Brew a read for all the step-by-step details.

If you took the sample after topping off with water, that dilution will make your efficiency look lower than it was.

bobwantbeer said:

I'm guessing somewhere between 75 and 79 degrees.

Click to expand...

Now I don't want you to get your feeligns hurt, OK? A lot of the beginner trouble we see around here starts from people not using a hydrometer at all. So you are at the head of the class already.

So was 1.035 the raw number that needs to be corrected for temp, or the sg you got _after_ you corrected for temp? Your hydrometer should have come with a piece of paper with some scratchings on it...

my buddy was saying we should take a reading before topping off, and I insisted we do it afterwards. Boy is my face red. Although we both participated in not having the mash water at the proper temp, and I think that seems to be the main issue.

We did not correct for temperature. 1.035 was the reading we got at that temperature. Someone posted a link for hydrometer temperature correction and it said at 77 degrees you add .002 to the reading. Which helps.

Did you mix the wort after topping off? If not your reading was probably lower still than you thought because the top off water wouldn't fully be mixed in yet. If this is the case your efficiency might not be too bad for a beginner.

bobwantbeer said:

After the boil I was at about 5 gallons, and I was shooting for 5.5 so I topped it off with a few more quarts of water. I rocked the carboy a few times to stir it in before taking a reading

Click to expand...

That's probably where your problem was.

At the end of the boil, you had 5 gallons of nice heavy wort (let's say with a gravity of 1.050). Then you add a couple of quarts of nice light water with a gravity of 1.000. The light water will simply sit on top of the wort. Rocking the carboy a few times is not enough to thoroughly mix the water with the wort. When you took the sample for the reading, you would have taken it from the top of the wort, and gotten a reading somewhere between the true gravity and the gravity of your top-off water.
It is quite possible that the true OG was in the region of 1.050, but you will never know unless you send me the entire batch for analysis after it is bottled.

-a.

edit. That's a long winded way of saying what joshpooh said.

When you get a chance, read this: http://howtobrew.com/section3/chapter18.html

Earlier in the book, he discusses the rationale behind it all, and it's good reading, but this is a step by step on how to do it the first time. I still refer to it often when I'm mashing. I liked it so much, I bought the hardcover book and use it all the time.

but I'm a pecimistic person. What about the fact that my strike temp was low? How badly should that effect my efficiency? I also did a decoction which may have raised me up to a more appropriate temp I guess. Thank you all for your help. It does have a nice marshmellow looking krausen on it and it's fermenting vigorously, so hopefully it'll be ok. You're all such beautiful people. Many thanks again.

bobwantbeer said:

I mashed in with six gallons at 154

Click to expand...

I'm more inclined to think that this is the crux of the problem. That's a REALLY thin mash! You probably should've mashed in with 2-3 gallons of water (at around 165-170 so that when you add the grain, the temp drops to your desired strike temp) and sparged with 5-7 gallons.

Also, most all grain brewers don't add any water after the boil unless the OG is really high. Adding water after the boil is mostly a partial boil extract technique.

At any rate, you should take the OG reading when all of the mashing, boiling, topping up, mixing, etc is done and you are ready to pitch the yeast.

bobwantbeer said:

but I'm a pecimistic person. What about the fact that my strike temp was low? How badly should that effect my efficiency? I also did a decoction which may have raised me up to a more appropriate temp I guess. Thank you all for your help. It does have a nice marshmellow looking krausen on it and it's fermenting vigorously, so hopefully it'll be ok. You're all such beautiful people. Many thanks again.

Click to expand...

Not to worry. If your strike temp was low, it just means your wort will be a little drier and thinner. So it might attenuate down to, say, 1.007 or something. No big deal, really. Just not exactly the beer you were expecting. But still beer, and probably good beer!

There are some really useful calculators here for strike temp, mash ratio, and determining if your tun can handle the grain you plan on mashing.

my mash temp should have been at 166. This was a very usefull experience though. I'm going to buy beertools and hopefully when I brew again next week I'll be right on target for my OG. Thanks again everybody.

You're welcome! And before you brew again, if you read that chapter in howtobrew, it'll make a big difference. It really helps you to visualize the process and he gives step by step instructions, like "check the hydrometer reading now", "check the temperature of the mash now". Even though you'd be using a different recipe, it still applies. And it's easy to follow but not condescending at all about the math and theories.