Reduce priming sugar for reduced batch?

[smetzger]

Hi there folks,

So I brewed my second batch of beer recently, an altbier, using a beginner kit with all extract. I carefully measured out five gallons of water 24 hours before my brew, and dechlorinated it using campden tablets, since Philadelphia's water is heavily chlorinated. I worried that having only 5 gallons on hand (3 for boiling and 2 for top-off) would be a bad idea since some might boil down, and I'd end up with less than 5 gallons of wort (the amount the recipe is supposed to make). This indeed occurred to my dismay.

Using some rudimentary measurements (seeing how far up the 7-gallon bucket the wort line goes), I've determined I probably have about 3.5 gallons of wort in my fermenter. (Next time I suppose I'll draw a line in my bucket to know where 5 gallons is, and I'll dechlorinate closer to 7 gallons the night before.) It's been in there about 2.5 weeks, and I think I'll probably bottle it in a day or so after I take another hydrometer reading. (It started at 1.062 - which seems way too high for the recipe - and it's now at about 1.012.) My main question is, since I have about 70% of the wort I'm supposed to, should I reduce the amount of priming sugar I use? Will the 5 oz. provided with the kit over-carbonate the beer? What do you guys and girls think?

Thanks,
Steve

 

[Suthrncomfrt1884]

Definately DON'T use all 5oz. You'll need around 3.3oz. to carbonate to 2.5 volumes assuming your wort is at 65F.

 

[smetzger]

Thanks for the speedy reply! I can guess, but what exactly is a volume? (Are there several "stages" of bottle carbonation, each being called a volume?) The temperature refers to the temp. it's at in the fermenter bucket, right? (It's been 63 typically, but it's been getting - very - slightly colder each day.) Lastly, can you think of a practical and less ridiculous way to come up with an estimate of my wort volume than measuring the bucket with a ruler?

 

[chapa]

The volume is how much co2(carbonation) is infused into the brew, based on how much priming sugar you use. Look up beer style carbonation volumes(I'd nab a link for you but I'm on my phone), and you'll find a basis of how much co2 you want with certain styles. Beersmith shows you all of this, and calculates how much sugar to add, based on how many gallons you have, and what volume of co2 you want to hit. I'd go for the higher side of the style since you said your OG came in higher than expected. Probably should have topped off, until you hit your target OG. Howtobrew.com is a GREAT reference for priming and everything in between.

As for marking your fermenter, you'll need to measure out each gallon, and mark the outside so you know exactly how much you have at all times. I used a graduated cylinder to measure out 1gallon in a "master measuring cup(I used a large dog food container that holds at least 1 full gallon)" and would use that to add 1gallon at a time to whatever it is I need to measure.