Calling all would be scientest

[seth8530]

The math seems to be straight-forward enough algebra.

The items which need work seem to be the big problem here.

I was worried, when I first read your post that there might be real math in there. I was almost expecting differentials or integrals, or at least a summation.

Nahh, no need for any of that right here. If we were tracking the rate of change of the sugar drop then we might start getting into some calculus, but their is a lot of very good things you can do with some rather pedestrian math skills as long as you think as math as a language and a tool.

 

[seth8530]

Ok, I have an update. I have managed to derive the next part of my ABV equation. The only thing that we are now missing is a correction factor on the ending brix to make up for the alcohol throwing off the measurement. Once this is done I believe that we will have an ABV equation that is based heavily on physics and chemistry instead of being data driven. Please give the attached PDF a look over. I have detialed the proccess I took to get my equation and shown every step along the way.

As of right now my equation tends to give results that are nearly 1% higher in abv than most of the existent equations, but with some work I am sure we can come up with the final brix factor to give us something a little bit better.

View attachment Seth's ABV Equation NO correction factor.pdf

 

[seth8530]

I have a potential solution. I managed to find an equation that emperically relate thetrue final brix to the change in brix.

 

[seth8530]

Ok, I am posting my approximation. I used an empirical relationship that relates the measured brix to the actual brix taking into account the alcohol shift. This is NOT perfect, however, I do believe it is rather good and is as good as if not better than the existing equations. The next step will be to make that FG non empirical and make it physics based.

Anyways long story short...

.53055*FG*(BrixI-BrixF)=ABV is my equation. I am attaching the current derivations as well in PDF form.

View attachment My_abv_equation_mk1.zip

 

[barryjo]

Mainly because why not. If you can do something better why not do it better? Also, when the alcohol content gets higher and higher the error will grow greater and greater.

If you want better, you could always invest in an ebulliometer. And I do mean Invest.
Personally, i prefer the Honneyman method. I run that while bottling.
Naturally the accuracy of anything depends on the test equipment used. And on the operator using it.
But for most winemaking, and especially when ingredients are added after fermentation stops, Honneyman works for me.

 

[manvsvine]

different yeasts have different levels of efficiencies at converting sugar into alcohol.
yeasts that have higher alcohol tolerances also tend to be more efficient at converting sugar into alcohol, where as other yeasts convert sugar into higher percentages of co2 . before you can come up with an accurate formula , you need to know what the co2/alcohol split is for what ever yeast you use. you can get a 1% alcohol difference between different yeasts at the same sugar level in the must. before you can calculate potential alcohol you need to know the efficiency quotient of the yeast. unfortunately for us its easier to work backwords , ie you know what your final alcohol level is from testing the finished wine and what your starting brix was so you can calculate the efficiency quotient of the yeast you just used.
but that would only be valid for that must as any other must has nutrient and temperature variables .

distillers making brandy seek out the most efficient yeasts possible , where as making dessert wine they seek out the least efficient and alcohol tolerance yeasts.

even lallemand could not come up with reliably accurate formula.

http://wineindustrynetwork.com/uploads/tips/gqRwa10bvFXsGDBIHfLKmE7A9yjiCt.pdf