Secondary fermentation questions

[hallerobin]

Hi, all!

I've got 2 questions that refer to the part of the process after cider is left to ferment totally (primary) and I've added fermentable sugar in order to both sweeten and carbonate (I have been bottle carbing and stovetop pasteurizing):

1) I know how to get the ABV of the product of primary fermentaion, but how does one calculate the ABV of the finished (bottle-carbed, stovetop-pasteurized during secondary) product?

2) Does anybody know of a way to naturally carb (using fermentable sugars) in a keg without it going totally dry? In other words, if I put the dry, primarily-fermented cider in a keg with fermentable sugar, is there a way to stop the carbonation at a particular point, in order to retain some of the sugar?

I hope those questions make sense and look forward to your thoughts!

 

[cluckk]

For the second question, once the cider gets to the gravity/carbonation you want cold crash it. Get it down cold as quickly as possible. I sit mine inside of our large chest freezer.

For question 1, the sugar you use to carbonate should be such a small amount that it will not make an appreciable difference in your ABV. The sugar that you use to sweeten, of course you don't want to ferment out (or it wouldn't be sweet) so there will be no change in the ABV. By the way, if you add fermentable sugar to backsweeten you will have to cold crash or use other methods (possibly metabisulfide?) to stop the fermentation, unless you have reached the maximum alcohol tolerance of the yeast.

Perhaps someone else will have better or more information.

 

[hallerobin]

Thanks, cluckk! I appreciate the quick and helpful reply!
A couple of clarifications that might help...

For the second question, once the cider gets to the gravity/carbonation you want cold crash it. Get it down cold as quickly as possible. I sit mine inside of our large chest freezer.

Yes, I can definitely see that working, and it's probably what I will end up doing. I guess I was looking for a way to permanently stop the process (kill the yeast). In theory, with a big enough tub and hot enough water, one could pasteurize the whole darn keg... but I don't know how that would realistically be done (short of a giant metal tub atop a propane burner or something!).

For question 1, the sugar you use to carbonate should be such a small amount that it will not make an appreciable difference in your ABV. The sugar that you use to sweeten, of course you don't want to ferment out (or it wouldn't be sweet) so there will be no change in the ABV. By the way, if you add fermentable sugar to backsweeten you will have to cold crash or use other methods (possibly metabisulfide?) to stop the fermentation, unless you have reached the maximum alcohol tolerance of the yeast.

Perhaps someone else will have better or more information.

So, I'm actually adding a fair amount of sweet stuff (usually some combination of apple juice concentrate, honey, and brown sugar) at the start of secondary--more than I need, given that I want some of it to ferment out and produce the carbonation (and given that I'm making cider on the sweeter, bubblier side). And rather than cold crashing or using any kind of tablets, I just pasteurize on the stovetop.

An example: I take a potential ABV reading of the juice before primary fermentation, and it is 6%, then I read it at 1% after primary. So, it is now approx 5% ABV. I can add my sugars, take another potential ABV reading and then read again when I decide to stop the secondary fermentation. Would the latter set of readings alone give me the final ABV, or would I need to take the 5% change from primary into consideration?