Double-check my Alc% calc

[Wade E]

I see where Al is going on this. How would you get an accurate reading with temps that low? I see what you are doing and have heard of this many times, its a sort of cheating way of making an "ice wine" style. Did you pull out a sample at times during thwing and warm them up to an acceptable level to test sg?

 

[jet]

are you saying that you took your sg while you still had frozen water...? if you did then fine that is your answer...

but i find it hard to believe anyone would take an sg reading w ice in the primary

i can see it as an experiment to see where it stands or to veer off in ones own direction and make something different...

Here's my blog post on this process:
http://someamateurfoodie.wordpress.com/2010/09/19/faux-ice-wine/

 

[AlFulchino]

now a quandry..i am not sure why you presented the question in the first place....i am reading your blog on this and you set out to do this and knew that a higher abv could be achieved or at least higher sweetness...i am assuming you trust your hydrometer...you stated that you started w five quarts then melted some and ended w under a gallon....well a gallon is 3.75 or 3.79 quarts....so that is the end of the story and you still had to have some ice (by what you wrote) and i am wondering now why we went thru the whole mystery and exercise if you knew this all along but did not fully share the background until now .... i am holding out final thoughts because then you mentioned you held back 10% of the must for backsweetening..is this for the same batch or another one...did you add sugar to this batch?

 

[BobF]

Yep, I come up with 21.72% If your sg's are right your yeast was crazy!!!!!!!

Wade - what formula did you use?

 

[Wade E]

starting sg - finish sg x 134.1. I think what Jet was wondering is how it fermented so far to get the almost 22%. Ive never seen a yeast go that far myself except for some of that nasty Turbo yeast which IMO leaves such a nasty taste in the end result I can unserstand why anyone uses it myself.

 

[jet]

I posted this question because I calculated the alcohol at 4% higher than the max for the yeast I used. I was hoping that someone would double-check my calc. They did and I appreciate that.

A high ABV was the goal, so that is not a problem. I just assumed the fermentation would leave a higher SG. No sugar was added to this batch. I used the reserved juice to back sweeten this batch after stabilizing and filtering.


IIRC, I adjusted the starting SG for temp. I have to assume that I messed up the initial SG. I think that is more likely than a superman yeast.

 

[Wade E]

The problem is that the adjust sg gets more and more inaccurate the farther away it gets from the target temp so that may play a role in this equation also.

 

[BobF]

starting sg - finish sg x 134.1. I think what Jet was wondering is how it fermented so far to get the almost 22%. Ive never seen a yeast go that far myself except for some of that nasty Turbo yeast which IMO leaves such a nasty taste in the end result I can unserstand why anyone uses it myself.

I was curious about your calc b/c it was different from the others. I'm collecting all of the different formulas people use. Thanx

 

[jet]

I was curious about your calc b/c it was different from the others. I'm collecting all of the different formulas people use. Thanx

Here's mine (it yields 22.01):
=(A29-A30)/0.00736

Where A29 is starting SG and A30 is the ending.

 

[AlFulchino]

"A high ABV was the goal, so that is not a problem. I just assumed the fermentation would leave a higher SG. No sugar was added to this batch. I used the reserved juice to back sweeten this batch after stabilizing and filtering."

ok, maybe it was not the goal....but....it *did* happen by your numbers.....and the question is *why*

so if we come back to the possibility that your initial sg is wrong then you could pick up a cheap vinomter and measure the alc with that...i think they go up only to 15% or so...but that is a cheap way to look at your alc level from another vantage point

 

[Wade E]

I dont think those vinometers are very accurate at all! I had one and threw the stupid thing away.

 

[jet]

I have a vinometer (somewhere) but also gave up using it because of the erratic results. Now that I have back sweetened, I don't think I can even try it.

I would not give this any more thought. At this point the wine is done. The only thing this will affect is what I print on the label, which (most likely) no one other than me will see.

If I do this again, I will just re-check the SG immediately before pitching the yeast.


Thanks all for your concern.