OG/FG...Again

[JeffoC6]

I've already started a thread on this before, but it kinda went south and the original questions were sort of lost. I'm asking again so I can take notes, learn, and move forward with my brewing experience.

I'm very confused, folks, and it's frustrating me. I want to be a good home brewer, but I feel like some things are making it difficult for me to do so.

I brew 1-gallon batches. That's all I can do right now. As much as I'd love to bump up to larger batches, it's simply not feasible at this point.

I've found that in my past 3 brews, I've either had inconsistent mash temps or not enough wort (due to boil off) at the end. I've since learned what I need to do to alleviate these issues...I hope.

Which leads me to OG and FG. Because I'm making such small batches, I'm not taking FG samples due to not wanting to lose some of my final product. I've read on here that I shouldn't worry about losing the beer, or that I could safely return the beer to the carboy after sampling, or that I should buy a refractometer. But I am worried about losing final product, and I very much don't want to return my samples to the carboy. Also, I don't have the money for a refractometer right now, but will...soon.

In the meantime, I'm just looking for some help with these next few questions.

1)If I'm not taking OG and FG samples, what's the worst that can happen? I'm leaving ALL of my first 3 brews in the primary for 3 weeks, and leaving the stout in my primary for 4 (see below in my signature), and then bottling.

2)If I were to start taking OG samples, when is the right time to do this? After I've extracted all of my sugars and before I boil? After my boil is completed and my wort is cooled? After my carboy is filled and topped off with water (before yeast is pitched)?

3)If my OG sample is, for the sake of argument, 1.033, and the target OG was 1.029, and I don't have any other means to adjust it....Then what? What actually will happen to my beer? Will it not be "good?" Or will it simply not be the way it was intended to drink? I'm not a beer afficienado. While I enjoy drinking beer...a lot, I'm not one to sit back and analyze the hop infusion, or the depth of the barley, etc. You know what I mean...So what does not hitting OG ultimately do?

Thank you for reading and offering suggestions. I do appreciate it.

 

[mikelikesit2000]

First off......Relax!

Your beer will be fine weather you take OG and FG readings. Most brewers I know rarely measure the gravity of there beer. All the OG does is let you know how much sugar is in your wort (potential alcohol) and FG tell you how much of the sugar was converted to alcohol.

Because your Doing 1 gallon batches it is going to be tough to get your OG/FGs right on the money every time. Use a software (beersmith) to make the recipe and just go for it. Its gonna be good beer as long as your clean and it ferments in the 68ish degree range.

 

[JeffoC6]

First off......Relax!

Your beer will be fine weather you take OG and FG readings. Most brewers I know rarely measure the gravity of there beer. All the OG does is let you know how much sugar is in your wort (potential alcohol) and FG tell you how much of the sugar was converted to alcohol.

Because your Doing 1 gallon batches it is going to be tough to get your OG/FGs right on the money every time. Use a software (beersmith) to make the recipe and just go for it. Its gonna be good beer as long as your clean and it ferments in the 68ish degree range.

Is beersmith free?

 

[Bhunter87]

Wow calm yourself!!

On when to take your gravity readings. Your OG should be taken pre yeast, post top off water aFTER your mix and aerate! (if you don't mix well, you'll get more water and less wort leaving you an incorrect reading) It's a good idea to check your temperature at the same time and record your findings. What you are doing is testing the amount of fermentables in your wort. It is not necessary to do this unless your want to know your ABV.

If you get a 2gal bucket from a hardware store and primary in that, you can make a slightly bigger batch to allow for taking readings. It's also fun to taste the wort when you take readings!!! You really only need to test it twice/three times which will amount to about a cup of beer total so if you do it, it won't hurt your batch too bad.

You should test pre-pitch and before you rack to secondary you'll test it twice. Once after you THINK fermentation has stopped... Wait three days.. And test again. If its the same... The yeasties are done.

Taste it every time!! It's great!

All this is not necessary though if you and just making beer but don't really give a crap. Just because your og isn't exactly what it is "supposed" to be, doesnt mean anything. Forget that!

Any other questions?

 

[wmarkw]

Jeff I agree man take it easy! Is your first batch ready to drink yet? lol I found a refractometer on ebay for $25 shipped. I might try that out so I can test my 1 gal batches. So far I have 5 bottled and drank 5 batches w/o any readings and they all tasted awesome. I have another 2 batches bottled and conditioning. I want to be good at this hobby too and the info here can be overwhelming but I say to myself, I'm starting out, follow the recipe, focus on getting my mash temp and the final product should turn out ok. I check my mash temp once and that is when I mix the grains with my water in my MLT. I know that I maybe lose 1 or 2 deg an hour so I know exactly what temp my water needs to be. From there I put the lid on the MLT set the timer for an hour and wait. Once I built the MLT the mashing process has been stress free.

I would like to know my ABV% since the info is given on every recipe it would be nice to know that I'm doing it correctly. But like I said all of my batches have tasted awesome and I could tell there was alchol in it. lol.

 

[Quadrupled]

1. In regards to not checking your FG and just going with 3 weeks in the primary, I would suggest that you be a little cautious. I have had a Kolsch in my primary for the past 3.5 weeks and it's still 6 points above the highest SG that I would expect. From experience with this beer, I know it has taken 4-5 weeks to get to it's FG. Since you aren't checking your FG, it may be worth considering bottling in 12 oz plastic pop bottles to prevent bottle bombs.

2. Both a preboil gravity and postboil gravity are taken. This allows you to calculate efficiencies, adjust hop additions. Also, if you know your preboil gravity is 1.020 in 2 gallons, you then know if your desired OG is 1.040, that you need to boil off one gallon. This prevents you from having to top off and essentially prevents question 3.

3. A few points either direction are negligible.

 

[venquessa]

Why not just leave the hydrometer in the carboy?

 

[JeffoC6]

So to get this straight...

--I finish my boil

--I put my pot in the ice bath and cool my wort below 70 degrees.

--Once cooled, I use a turkey baster to take a sample, take the temperature of my wort and take my hydrometer reading. Then, using this calculator http://www.brewersfriend.com/hydrometer-temp/ I determine my OG?

--Then, if I "top off" with spring water after putting in my 1-Gallon carboy, I don't take another reading? Or I do? If I don't...Ok. If I do...What's the true OG?

 

[pksmitty]

OG should be taken pre-pitch but post top-off. Be sure to mix the wort and top-off water very thoroughly (more mixing time than you would think) or else your OG reading will be low.

FG should be taken post-fermentation with a hydrometer. Alcohol in the beer will throw off a refractometer. Be sure FG readings are steady for 3 days before bottling.

FG readings not only allow you to calculate the alcohol in your beer, they also let you know that fermentation is actually complete before you bottle. Otherwise you risk bottle bombs.

Beersmith is a free download for a 21 day trial. $28 to purchase. Worth every penny, IMO.

 

[Bhunter87]

No

1. Top off, then test

Then ferment until it clears

2.Test

Wait 3 days

3,Test again

If 2 and 3 are the same

Rack to secondary

Wait a month

Bottle

 

[venquessa]

Just be careful with your hydrometer calibration. 99.9% of people talk of hydrometers calibrated for 60F, but if your hydrometer is designed specifically for brewing wine/beer it will often be calibrated to a much more appropriate 20C/68F, like mine is.

It "should" have it printed on the scale or in the instructions.

 

[JeffoC6]

No

1. Top off, then test

The ferment until it clears

2.Test

Wait 3 days

3,Test again

If 2 and 3 are the same

Rack

Bottle

Ok...Another few questions...Sorry to be a pain....

When I top off and test, am I first "mixing" the wort and the top off water? Kinda giving it a good shake? And then test? And THEN pitch the yeast after I've tested, right?

Secondly...Once I've tested, that's my OG, right? What if my OG is not the same as the recipes? Let's say it's lower...Then what? Let's say it's higher...Then what?

 

[venquessa]

When I top off and test, am I first "mixing" the wort and the top off water? Kinda giving it a good shake? And then test? And THEN pitch the yeast after I've tested, right?

Secondly...Once I've tested, that's my OG, right? What if my OG is not the same as the recipes? Let's say it's lower...Then what? Let's say it's higher...Then what?

1. Yes.

2. Not much you can do, unless you want to add sugar to lift the OG. If it's lower, then you didn't get the conversion the recipe expected. If it's higher, you got more. If it's lower, you have less "potential" alcohol. If it's higher you have more "potential" alcohol.

 

[Bhunter87]

Yes. Mix the crap out of it first. You want all water and wort mixed pre test plus it aerates it!

Forget if it's not exact. If its 1.00 off.. Then worry if it's .1 off, don't

 

[JeffoC6]

Great...Thanks guys, this is REALLY helping me.

Here's the calculator I have saved:
http://www.brewersfriend.com/hydrometer-temp/

By using this calculator, my hydrometer doesn't really have to be "calibrated," right?

 

[venquessa]

Hydrometers are calibrated to 15 °C, 59 °F. This calculator will tell you the actual specific gravity no matter what temperature the sample is at.

Is WRONG!

Hydrometers are calibrated to whatever the manufacturer wants to.

It will say on the instructions or on the scale on the device itself.

Mine is calibrated to 20C.

EDIT: But to answer your questions, you don't "calibrate" the hydrometer, you simply adjust based on the difference between the samlpe temp and the hydrometer's calibrated temp.

 

[Bhunter87]

Is WRONG!

Hydrometers are calibrated to whatever the manufacturer wants to.

It will say on the instructions or on the scale on the device itself.

Mine is calibrated to 20C.

+1

Temp matter

 

[JeffoC6]

+1

Temp matter

OK, so I'm looking at my hydrometer right now. It says specific gravity temp 60*.

So let's say I take the temp of my wort/top off water mixture and its...55 degrees. What do I do?

 

[Bhunter87]

There are calcs out there that account for temp. Hang on

http://www.rooftopbrew.net/abv.php

 

[JeffoC6]

There are calcs out there that account for temp. Hang on

http://www.rooftopbrew.net/abv.php

I'm really sorry to be a bother, but...how does this work?

Let's use these numbers:
Water/wort mixture...Temp is 64 degrees
Hydrometer reading of this mixture is....1.0526

What do I input in here to find my OG?

 

[Hang Glider]

64 is close enough to 60 that you're only talking half a point or less - so when you input your values here it doesn't really change much. This website link is calibrated to 59F, close enough to your hydrometer's 60F

Play around - change the temp to 90 (in case you took your sample while a bit warm) - see what that does.

Don't rush to get your refractometer until you're doing larger batches - it really doesn't help with FG - only helps you determine what to adjust when you measure pre-boil & post-boil numbers. FG numbers on a refractometer need adjusting because of the presence of alcohol (not present during OG).

 

[JeffoC6]

64 is close enough to 60 that you're only talking half a point or less - so when you input your values here it doesn't really change much.

Play around - change the temp to 90 (in case you took your sample while a bit warm) - see what that does.

Don't rush to get your refractometer until you're doing larger batches - it really doesn't help with FG - only helps you determine what to adjust when you measure pre-boil & post-boil numbers. FG numbers on a refractometer need adjusting because of the presence of alcohol (not present during OG).

I was told earlier in this threat that because my hydrometer is calibrated to 60, I shouldn't use that link you provided, because that's for a hydrometer calibrated at 59?

 

[Hang Glider]

edited my above post...
59 and 60 are really close...no worries. Mine is calibrated to 60 also, and I use this.

Really, there is no discernible difference between 1.052 and 1.0524

If you get 1.030...or 1.065 - when you're expecting 1.050 --- now that's a difference that you might be concerned with, requiring more malt or more boil off, or more top-off water...

 

[JeffoC6]

edited my above post...
59 and 60 are really close...no worries. Mine is calibrated to 60 also, and I use this.

Really, there is no discernible difference between 1.052 and 1.0524

If you get 1.030...or 1.065 - when you're expecting 1.050 --- now that's a difference that you might be concerned with, requiring more malt or more boil off, or more top-off water...

Thanks...So to clarify (sorry, I'm kind of ADD)...

I want to take my wort/top off water mixture and put it in the test tube. Then take it's temp (will most likely below 70*)...Then, I'll record the hydrometer reading. I'll put the temp I took, and the reading I took, in this calculator: http://www.brewersfriend.com/hydrometer-temp/ and record the "adjusted value" as my OG.....Right?

 

[Bhunter87]

Your OG is you hydro reading pre ferment. FG is reading after it ferments out completely.

The 1 degree difference will not change your numbers enough to worry about. Like ^ said, when it's over .010 different than what the kit says, then you might have done something wrong. Don't fret a small difference. It might be a little off if you're a little heavy or light on top of water, hardness of water, altitude blah blah.

Until there is a big difference, just relax! This is meant to be fun, not stressful

 

[venquessa]

Sounds good to me.

 

[Bhunter87]

Thanks...So to clarify (sorry, I'm kind of ADD)...

I want to take my wort/top off water mixture and put it in the test tube. Then take it's temp (will most likely below 70*)...Then, I'll record the hydrometer reading. I'll put the temp I took, and the reading I took, in this calculator: http://www.brewersfriend.com/hydrometer-temp/ and record the "adjusted value" as my OG.....Right?

No.

You won't use this until fermentation has stopped.

Take a reading with your wort/top off. THAT is your OG. Take a temp reading in your carboy. Not the test tube.

 

[JeffoC6]

No.

You won't use this until fermentation has stopped.

Take a reading with your wort/top off. THAT is your OG. Take a temp reading in your carboy. Not the test tube.

So it doesn't matter what the temperature is of my wort/top-off water mixture is? I just take a sample of it and take a hydrometer reading, regardless of temp?

But later, when fermentation stops, I DO take the temp of the wort? Then take the reading, and use the calculator?

 

[Bhunter87]

So it doesn't matter what the temperature is of my wort/top-off water mixture is? I just take a sample of it and take a hydrometer reading, regardless of temp?

But later, when fermentation stops, I DO take the temp of the wort? Then take the reading, and use the calculator?

Take a temp in carboy before pitching. Record it with your OG.

Do the same with FG and then enter your info in the calc

 

[JeffoC6]

Take a temp in carboy before pitching. Record it with your OG.

Do the same with FG and then enter your info in the calc

Right- but isn't taking the temp in the carboy before pitching the same as taking the temp of the wort that I collected from the carboy and put into the hydrometer test tube?

I'm really sorry to be such a pain. I owe you a beer.