Alcohol content/hydrometer questions

Hey, guys. So my brewing partner and i brewed our first batch a few months back. We decided on a Kiwi wit. We let it sit in the primary for 14 days (as the book suggested) and the primary for 10 days. We bottled it 10 days ago. So today i popped one open, we have them in 1 liter swing tops and DAMN! are they carbonated. But i took a hydrometer reading and it says we only have 3 to 4 percent alcohol in them?? hmm this throws me off. i've had 1 bottle of them and shoot it kinda tore me up ha. could my hydrometer be off? am i reading it wrong? did i not let them condition in the bottles long enough? they taste nice and smooth and very drinkable like a wit should be, but i just feel im doing something wrong. the book said it would be 5% does leaving them in the fermenters longer give more %? any advice would rock. Thanks, Fellas! CHEERS!

You cannot determine ABV with a single measurement. You need to know starting gravity and final gravity. The difference multiplied by 131.25 will give you ABV.

Make sure you read the scale with numbers like 1.060 and 1.010. The scale with % will not help you.

My first brew, a 3.9% abv beer about knocked me on my ass. I figured it was a big gravity reading error on my part.

Damn, i didn't know that about the gravity. Thanks. Yeah this beer has my number and i consider myself seasoned in the beer assimilation dept, but whoa! being as we didn't take a reading in the beginning i may never know for this particular beer.

Was it an extract batch? If so, the recipe likely lists OG, FG, and ABV. If it doesn't, post the recipe and someone will probably run it through some brewing software to tell you.

Yeah, it was an extract batch, out of the book "extreme brewing." Beer name "kiwi wheat (WIT)"

The % alcohol scale on the hydrometer is really a "potential % alcohol" scale and is primarily used by wine/cider makers to know where their product will likely end up. Basically, it tells you approximately what the ABV % would be if all of the sugars in the sample were fermented out (which happens with wine and cider). Beer does not ferment out completely so this scale is pretty much useless brewing beer.

As already mentioned, use the specific gravity scale to get your original gravity (OG) and a final gravity (FG). OG will generally be from 1.040 and up (though mostly in the 1.045 - 1.075 range unless you are making very strong beers). FG will generally fall between 1.010 and 1.020.

You can then estimate ABV by the following formula:
ABV(%) = (OG - FG) x 131

Ramiz09 said:

Yeah, it was an extract batch, out of the book "extreme brewing." Beer name "kiwi wheat (WIT)"

Click to expand...

If you followed the recipe to a "T" the OG is in the book as I remember....