So I'm from Minnesota, but living in DC. I've done some one gallon batches using apple juice. It's fall here, (how's the weather back home?) so I told my wife to pick up 5 gals of cider (stuff's heavy) and she brought me 5 plastic jugs of Ziegler's from Giant Foods (kinda like Red Owl for you MN types, yeah, I left awhile back).
Which has potassium sorbate, allegedly unfriendly to yeast. It tastes fine out of the jug. It's cloudy, but it has, like, potassium sorbate.
Some guy on the internet said no problem. Culture and pitch some baker's yeast in that cider. It won't be able to effect mitosis, but al the happy yeast will ferment and clean out the potassium sorbate. They don't have to multiply. Just let them sputter out.
THEN pitch your champagne yeast and any other additives (I was going to put in enough brown sugar to get a 20% alcohol content outcome) and it will proceed normally. Since it was on the Internet, as I always do, I assumed it must be true.
I pitched a furiously bubbing Hodgson Mill dry yeast starter I had prepared with DME and some ground up vitamins that had some of stuff (plus other stuff not) typically found in yeast nutrient kits, into the BigMouth Bubbler(TM) that I bought from NB, with the cider on September 28. OG was 1.05. Two days later it was burping 13 bubbles per minute through the airlock (the peak) settling to 4.5 by October 4. It is now burping only occasionally.
Tonight I took an OG. 1.004. The brewer's friend online calculator sez that's about 6.43% ABV. Better yet, it tastes great, nothing like the apple juice gallon batches I've made from frozen concentrate (which had no added preservatives). A lot of the brown particulate seems to have settled out, it is now more yellow in color, pleasing to the eye. Hence, my dilemma.
I feel like putting this awesome stuff into a secondary for a week or two, and bottle conditioning it in champagne magnums with enough sugar to produce a sparkling wine level of carbonation. If I got a carbonated version with this taste, maybe a little less sweet, that would be a major victory. I would make it every year. I would post, despite being a new brewer, authoritative Ziegler hard cider recipes online, telling people not to worry about potassium sorbate. That it is all old wive's tales.
But I'm worried that I missed something. This was supposed to be a two-step, esoteric approach to fix a bone-headed purchase. (Rural Virginia is 30 minutes away, and has unpasteurized cider practically flowing in the storm drains). It should not have worked, producing an acceptable tasting, alchohol-positive product without proceeding to step two. Plus that extra sugar worries me. Maybe if I bottled it, even in magnums, it would blow them up or spout foam til the bottles empty because there is still too much sugar. My other apple juice ciders were dry, except for the ones I put a packet or two of Equal into.
So. What should I do? Proceed according to plan? Stop while I'm ahead?