[DieselGopher]

I tried to use the spreadsheet (from the FAQ) to get the numbers I am looking for but it didn't seem to work. If anyone can help explain how to use that, or help me out otherwise, much appreciated.

Base mead was 24 lbs of light amber honey, 7 gallons total volume, O.G. was 1.124
Used EC-1118 yeast cause I knew this was going to be a monster. End of primary SG was about 1.000.

For secondary, racked onto 5 cans of fruit puree:

1 can (3 lbs) Oregon blackberry puree
1 can (3 lbs) Oregon bluberry puree
1 can (3 lbs) Oregon raspberry puree
1 can (3 lbs) Oregon cherry puree
1 can (6 lbs) Strawberry wine base

The mead chewed through alot of the fruit, it bubbled for another 2 months on the fruit. I just transfered tonight off the fruit sludge, SG was 0.998. I am looking for approximate ABV, I understand it may be difficult to get exact, but just put me in the ball park. Thanks in advance.

Matt

[zymot]

The rudimentary formula for calculating ABV is original gravity minus final gravity.

Since you do not know your original gravity because you do not know how much sugar is in the puree you added, the best you do is guess. See if somebody knows what the gravity is of those pure.

For beer you can take finished beer and read gravity with a hydrometer and read brix with a refractometer and calculate OG and ABV from those two measurements. I assume (hope) gravity is gravity. If it comes from honey, malt, raspberry, sugar makes no difference. [if I am wrong, somebody is welcome to chime in]

http://www.onebeer.n...actometer.shtml

If you got access to a refractometer, you are in business.

zymot

[Wayne B]

zymot, on 04 February 2010 - 08:48 PM, said:

The rudimentary formula for calculating ABV is original gravity minus final gravity.

That statement isn't correct. There is significant error if you use that "rule of thumb" for anything that attenuates as much as mead must usually does.

However, you can get a rough estimate of ABV from dual readings - refractometer and hydrometer. In that sense "gravity is gravity."

[zymot]

Wayne B, on 05 February 2010 - 08:30 AM, said:

That statement isn't correct. There is significant error if you use that "rule of thumb" for anything that attenuates as much as mead must usually does.

Hence the use of the term rudimentary.

Quote

1. basic; fundamental; not elaborated or perfected

The point is you have to know the start point and the end point and then can make calculations from there. Without the starting point, you have nowhere to go.

Wayne B, on 05 February 2010 - 08:30 AM, said:

However, you can get a rough estimate of ABV from dual readings - refractometer and hydrometer. In that sense "gravity is gravity."

If you can treat a mead with fruit puree added as gravity is gravity, then the hydrometer & refractometer method should be as accurate as any other method using the same measuring instruments.

zymot

[psolio]

DieselGopher, on 04 February 2010 - 08:00 PM, said:

Base mead was 24 lbs of light amber honey, 7 gallons total volume, O.G. was 1.124
End of primary SG was about 1.000.

1 can (3 lbs) Oregon blackberry puree
1 can (3 lbs) Oregon bluberry puree
1 can (3 lbs) Oregon raspberry puree
1 can (3 lbs) Oregon cherry puree
1 can (6 lbs) Strawberry wine base

SG was 0.998. I am looking for approximate ABV

I was able to get a decent estimate, given the above assumptions.

Oregon Fruit Purees lists the Brix for their products on their website:
12 (1.048) - Oregon blackberry puree
12 (1.048) - Oregon bluberry puree
12 (1.048) - Oregon raspberry puree
18 (1.074)[sweet]/13 (1.053)[sour] - Oregon cherry puree

I assumed the strawberry wine base is something like Vintner's Harvest, which is 100% fruit in its own juices.

With those added assumptions, I get a total volume of about 8 gallons, estimated SG 1.008, ABV before fruit 16.6%, ABV after fruit (before fermentation) 14.1% diluted, FG of 0.998 (from above), and a final ABV of 15.3%

These are all estimates, of course, without knowing exact volumes and specific gravities of your additions.

[Wayne B]

Nice detective work! I couldn't find those Brix values, but then I wasn't checking the Oregon Fruit website (Doh!).

[Wayne B]

BTW, if all you have are final gravity readings (from an accurate hydrometer) and final Brix readings (from a refractometer), you can use the following to approximate the ABV:

ABV percentage = [(Br x 4.16) – (SG x 1000) + 1000] x 0.365

where Br = the Brix value, measured by the refractometer
and SG = the specific gravity, measured by the hydrometer.

Note that when using the differential between ending hydrometer gravity readings and apparent Brix in this way, small errors in the measurement of either quantity will throw off your calculated ABV by a significant amount. Measure carefully.

[DieselGopher]

Wayne B, on 05 February 2010 - 02:12 PM, said:

Nice detective work! I couldn't find those Brix values, but then I wasn't checking the Oregon Fruit website (Doh!).

Neither could I!! Worst part is, I thought I saw them somewhere on the site several months ago.

Nice work psolio!! I really appreciate the help. Now the problem will be waiting another 2 years to get into this one.