Beer Forum

Ok gang, this one ought to be simple for most of you out there. Plain and simple I've got seven gallons of beer on a recent batch. How much corn sugar is needed to prime this amount of beer? I know how much it takes to prime five gallons but seven, I'm not sure. Any help would be appreciated.
Steve

7/5 or 1.4x the amount you would use for 5 gallons, assuming you are packaging the beer in the same size containers (12 oz bottles, for instance).

Steve wrote:Ok gang, this one ought to be simple for most of you out there. Plain and simple I've got seven gallons of beer on a recent batch. How much corn sugar is needed to prime this amount of beer? I know how much it takes to prime five gallons but seven, I'm not sure. Any help would be appreciated.
Steve

Gee guy's I realize that this was a relativly dumb question but not to worry I figured it out. I was obviously on a brief mental vacation but I'm back now.
Steve

I think nobody answered because DannyW did a good job already.

SunkenBier wrote:I think nobody answered because DannyW did a good job already.

Well, here it is sampling day! I guess I was hoping for some other type of answer on this question but those given seem to have been straight forward enough and gave me what I needed. Now to make a short story long it seemed logical to divide the 3/4 cup of corn sugar into five equal measurments and gather the weight of one of those measurments then use that to figure for my finished volumes priming rate. OK, that should work, yet I'm coming up a bit light on the carbonation. hmmm. My guess is to rouse the finshed bottles in the case a bit to see if the remainder will give me a bit more fizz. Either that or say the hell with this bottling crap and move on to kegging like I should have years ago! I know which direction I'm leaning but that doesn't answer my burning little questions now does it.

Steve

First off, weigh your priming sugar for most accurate results. Volumetric measurements will vary a bunch based on how you pack (or don't) your measuring cup or spoon.

Working with small amounts (like 1/5 of 3/4 of a cup) then multiplying will exaggerate any errors, so if you are a little low on your initial split you will be a lot low when you multiply it out.

If you want a more specific answer for figuring your priming sugar, then try this on for size.

When priming with sucrose (table sugar, brown sugar) use 4g/liter/CO2volume. If you are using dextrose (corn sugar) use 4.6g/L/Vol. Remember to subtract out your residual CO2 left over from fermentation. At ale temps, that will be around 1.0 volumes.

Typical homebrew carbonation is 2.4 volumes. So for your 7 gallon (26.6L) batch, primed with corn sugar, you would use:

4.6g * 26.6L * (2.4vol - 1.0vol) = 171.3g of corn sugar (dextrose).

If you are using table sugar, use this much:

4.0g * 26.6L * (2.4vol - 1.ovol) = 149.0g of table sugar (sucrose)

Is that more what you had in mind?