How Can I Find the Alcohol Content of Mead With Only Final Reading?

• #two

Hi Raguido - and welcome. Don't you need to know the initial gravity( or Brix) to exist able to use a figurer to decide the bodily ABV? I can first with whatever SG (or Brix) and ferment down to a gravity, say , of .996. How on earth volition a calculator be able to tell me whether my starting gravity was 1.100 or 1.090 or one.050 and if information technology cannot do that then the figurer cannot in fact tell me whether this batch is 13% or 12% or 7% ABV. My hydrometer (as does my refractometer) has a column for Brix and 1 for SG. (Rule of thumb Brix is about ane/four of SG) These are just alternative means of measuring density. I guess I don't understand how any calculator can provide a datum about initial density that cannot exist known from a concluding density.

• #4

How? A practical example: My last gravity is 1.008 which is the same equally a Brix of 2.05. What does your calculator tell me nearly the ABV of this wine? Unless your point about knowing the Brix is knowing the Brix of the fruit before I pitched the yeast but knowing the Brix of the fruit is exactly the same equally knowing the SG at the start. If that is all your computer does all information technology does is catechumen Brix to SG and as I said in my response to your first mail service - yous can more or less presume that SG is the aforementioned every bit 4 times the Brix.

• Thread Starter
• #5

You can't calculate the %ABV from just the final SG. You demand to accept the initial SG every bit well. In my case, I didn't have that number and then I couldn't calculate it as is normally done:

%ABV = (SG_initial - SG_final)/0.0074

If you know the initial SG, then you can calculate the %ABV in this way. I didn't accept that number for that batch of wine. But if I accept BOTH the final SG too equally the Brix pf the wine measured with the refractometer, I can so summate the %ABV via the formula listed in my first posting.

Last edited: February 11, 2018

• #6

Simpler, if you lot know the starting gravity and the finishing gravity to multiply the difference by 131 (ball park accurate enough)

• #7

I don't take fourth dimension to test this then I'll take you word. Simply, it doesn't audio right. You are taking a refractometer reading and a hydrometer reading of the finished wine. Without knowing the original gravity or the original brix, how does the calculation take into account the attenuation achieved. For instance 1 yeast may have a wine from 1.100 to .998 and some other may have the aforementioned wine from 1.100 to .990. The two would be different, but the difference betwixt the last brix and concluding SG readings should exist similar.

• #8

But if I accept BOTH the final SG as well equally the Brix pf the vino measured with the refractometer

Yes information technology is theoretically possible to measure both the hydrometer SG and a refractometer "brix" value to guess the residual saccharide and booze in a beverage. This is considering the index of refraction (reported by the refractometer as brix) volition answer the to both the dissolved sugar and the alcohol with a different relationship than the style the SG hydrometer measurements answer. Yet careful calibration must exist made and the SG must be corrected for temperature. Also the relationships are not purely linear. And then, it is theoretically possible but practically hard.

• #nine

Here is a page describing the process......... I personally consider it a bit absurd. Accuracy is liable to be poor without extremely high quality devices, and a closely controlled and corrected process.

https://www.bellinghamandstanley.com/ltd/abv_kit.html

And information technology begs the question "what does information technology thing?" Terminal ABV is final ABV, and there is nothing y'all tin can do about it except fortify or dilute. The reason we have FG readings is to ensure fermentation is consummate, the actual ABV result is just a matter of curiosity, not a value that is of any real utilise to u.s.. Exercise I actually care if my ABV is 5% or 6.5%? And if I know, what will I use that data for in the real world?
The only real reason I take an OG is to know how efficient my process is. The only reason I ever take an FG is to ensure fermentation is complete. I've often brewed taking neither reading, and y'all know what? The beer is indistinguishable from beer I took readings on. I exercise non bottle with crown caps. I more often than not keg now, and when I do canteen, it's with EZCap bottles, rated at well in excess of 100 psi, that I know will vent long before they tin grenade, though I've never had that problem. I oft use a hydrometer to monitor conversion, specially when doing a very short mash, as with last week'due south brew, when I did a 15 minute mash to increase torso, as I lacked whatsoever carapils. Also with my habitation malted grain, I take refractometer readings during the mash due to the lower diastatic power. If I'm not satisfied, I volition add some amylase, give it a bit more fourth dimension, and recheck. It serves in lieu of an iodine exam.

H.Westward.

• #10

right, just beer ain't wine and vino own't mead. A mead maker can accept a starting gravity of 1.150 (Basics I know, but information technology takes merely 4.25 lbs of love in that gallon to striking that SG and that SG volition produce an ABV of about xx% and realizing that the mead is probable to be rocket fuel may encourage the mead maker to detect means to reduce that outcome only unless y'all know the starting gravity you accept no way of being able to make up one's mind information technology by simply knowing the final gravity OR Brix. However, if you KNOW the starting gravity (or Brix) then you CAN utilise a refractomer to calculate/measure the gravity or Brix even if there is alcohol nowadays merely THAT is not what raguido is suggesting.

weeksvocassithand.blogspot.com

Source: https://www.homebrewtalk.com/threads/calculating-abv-without-the-initial-specific-gravity.644720/

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