Specific Gravity / % and I'm confused...

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mopie992

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Ok so I've been reading here for a while but this is my first post.

Years ago I brewed up a few batches of beer, no super success so I stopped.
couple of weeks ago I decided to try it again.
I dug out all my equipment, cleaned/sanitized and bought a Kit, a Brew House Prairie Wheat kit.

Ive done the primary fermentation and the OG was 1.042, which the kit said was within range of what it should be
at racking to the carboy 3.5 days later the SG was 1.030.
now 1 week into sitting quietly in the carboy the SG is 1.005.

According to the chart with my hydrometer that puts the alcohol around .5%
according to the brewhouse website the beer will be 1.045-1.047 at FG (http://www.thebrewhouse.com/technical/index.htm)

With this kit, the instructions doesnt have me mixing the sugar (dextrose in this kit) until bottling time.

So my question is, and the kit's instructions dont have any mention of this.
when adding the sugar at the bottling stage is that when the alcohol process begins and it will increase? or is that for carbonating? and lastly, have I made a batch really low alcohol beer?

Thanks in advance and bottoms up!

Mopie
 
to figure the alcohol by volume take the (OG - EG) x 131

in your case (1.042 - 1.005) x 131 = 4.8% ABV

4.8% ABV is middle of the road for alcohol strength and is very appropriate for many styles.

The small amount of sugar you add at the bottling time is intended to carbonate the bottles.
 
I think your math is off by a factor of 10. Your brew should be about 4.9% ABV if your SG measurements were taken at the right temperature.
 
Ive done the primary fermentation and the OG was 1.042, which the kit said was within range of what it should be
at racking to the carboy 3.5 days later the SG was 1.030.
now 1 week into sitting quietly in the carboy the SG is 1.005.

According to the chart with my hydrometer that puts the alcohol around .5%

Either that chart is messed up or you are reading it incorrectly. Your alcohol %age is way higher than .5% ABV.

I bet you're looking at the alcohol scale on the hydrometer itself. Ignore that. It's a "potential ABV" scale meaning that if the gravity fell to zero-ish from that point, that's what the resulting ABV would be. It's used mainly by wine makers at the start of fermentation. You only care about the gravity, ignore the other scales on the hydrometer.

So my question is, and the kit's instructions dont have any mention of this.
when adding the sugar at the bottling stage is that when the alcohol process begins and it will increase? or is that for carbonating? and lastly, have I made a batch really low alcohol beer?

The "alcohol process" is fermentation. The yeast is eating the sugar and pooping out alcohol as well as burping out CO2. The gravity measurements you take are basically measuring the amount of sugar in the beer. As the gravity falls, that means more sugar is being converted into alcohol and CO2.

When you bottle, you'll up the ABV a little bit more (like .5%) because you've added more sugar for the yeast to eat. In this process, you're concerned with getting CO2 in order to carb the beer..
 
Mopie, next time ignore what the instructions say and wait to rack to your secondary at least until your fermentation is done (your SG is the same for 3 days). Better yet, let it sit for a couple of weeks. The secondary is strictly for clearing, not actual fermentation. If you take it off the yeast too soon, you may never get to your final gravity. Plus, if you let it go a little longer, the yeast will clean up after themselves and make a cleaner beer.
 
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