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Low OG. Panic level 8.

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wwright

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Just made a wheat extract beer. OG 1.034. Supposed to be 1.040-1.045. Irate. How in the world can one mess up an extract? They freaking give you the sugar! My boil was 4 gallons. Suggested was 2-3 gallons. Left top of pot off so a lot of water would evaporate. Topped off with boiled water in fridge overnight. Why is my OG so low? Can I raise it? Can I dump table sugar in? Add more candi sugar tomorrow? Help!!
 
Frequent question from new brewers.

You're right, they give you the sugar, and you can't mess it up.

Here's the issue: You topped off with water. When you top off with water, the water and the wort are dramatically different densities and do not mix easily (think dumping honey into water- it just falls to the bottom). When you took a sample for the hydrometer, you actually grabbed more top off water than you did wort, and as a result the reading seemed artificially low.

If you added everything you were supposed to (nothing less, nothing more), and have the right volume (if they call for 5 gallons, and you have 5 gallons, not 4.5 or 5.5), then your OG is accurate to the recipe, and you can just ignore what the hydrometer says. It'll take a veritable asston of mixing to get a truly representative sample, and even then you can't trust it.

You're actually better served reading the sample before you top off. Then you take that reading (which will be much higher than the recipe's OG) and mathematically convert it. That's what I did every time with partial boils. You lose the margin for error.
 
Did you put the yeast in yet? You can still add more sugar into the wort to raise the ABV. The problem is how you will mix it since you dont want to oxydize! Corn sugar would be the best solution i think. Try moving with a spoon or paddle very very slowly.

Or you can think of it as a very light beer. Its not a critical mistake for a new brewer.


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Frequent question from new brewers.

You're right, they give you the sugar, and you can't mess it up.

Here's the issue: You topped off with water. When you top off with water, the water and the wort are dramatically different densities and do not mix easily (think dumping honey into water- it just falls to the bottom). When you took a sample for the hydrometer, you actually grabbed more top off water than you did wort, and as a result the reading seemed artificially low.

If you added everything you were supposed to (nothing less, nothing more), and have the right volume (if they call for 5 gallons, and you have 5 gallons, not 4.5 or 5.5), then your OG is accurate to the recipe, and you can just ignore what the hydrometer says. It'll take a veritable asston of mixing to get a truly representative sample, and even then you can't trust it.

You're actually better served reading the sample before you top off. Then you take that reading (which will be much higher than the recipe's OG) and mathematically convert it. That's what I did every time with partial boils. You lose the margin for error.


Despite my beer never actually being ruined, it feels like you just saved it. Thank you my friend. Awesome news.
 
I second the firt response, the wort was not thoroughly mixed. This happened to me a lot when I did partial boils until I did the measure Gravity and covert. For instance:

3 gallons at OG of 1.050.

Drop the 1.0 and you have 50 gravity points in 3 gallons, so 150 total gravity points (3x50, makes sense right?)

Now top off to 5 gallons and you still have that 150 gravity points. (150/5 = 30 gravity points per gallon)

So add back the 1.0 and 1.030 would be your new gravity at 5 gallons.
 
I second the firt response, the wort was not thoroughly mixed. This happened to me a lot when I did partial boils until I did the measure Gravity and covert. For instance:

3 gallons at OG of 1.050.

Drop the 1.0 and you have 50 gravity points in 3 gallons, so 150 total gravity points (3x50, makes sense right?)

Now top off to 5 gallons and you still have that 150 gravity points. (150/5 = 30 gravity points per gallon)

So add back the 1.0 and 1.030 would be your new gravity at 5 gallons.

Yep.

Volume 1 x Gravity at volume one (in that short form) = Volume 2 x Gravity at Volume 2.

Another easy example. If you have 2.5 gallons of wort after the boil at 1.080, and you top off to 5 gallons with water, 2.5 x 80 = 5 x gravity after top off, and you get 40, or a 1.040 OG.

Basically the sugar content is there regardless of volume, and all you're doing when you top off is diluting, which can be calculated mathematically. In the above example, that's pretty easy to see. Dilute it by 50%, and the gravity is cut exactly in half.
 
At this point(especially of you've already pitched yeast and its fermenting) there's no way to get a reliable OG. Because its going to change daily while fermentation is going on. Like stated above if you used all the ingredients and ended up with the correct volume for the ingredients you can pretty Mich take the expected OG for the kit as right. Or very close. Your best bet at this point is to focus on where you end up on final gravity compared to what it should be.

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So when should I take a reading to get a reliable OG?

For this beer, nothing you can do. Assume the recipe is accurate, and move along with the process.

In the future, you can do it the way we described, although with the caveat that it only works when you know the post-boil volume accurately. Any inaccuracy in volume measurement means inaccuracy in converted result. However, if you can measure volume accurately, then you can take a sample from the wort after it's chilled, but before you top off with water.

Alternatively, with an extract batch, you can trust that as long as your recipe is from a reputable source, and you add the right amounts of what they tell you to add, and you have the right volume into the fermenter, that your OG will be right and you don't even have to bother measuring.

You can also do it the way you've been doing, but shake the ever loving piss out of the wort for a couple minutes after you've topped off. Will get you a much more accurate reading (although might still be a couple points off one way or the other), plus the added benefit of helping aerate, which is VERY good for your beer, and most new brewers don't do it nearly enough.
 

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