Any hope of backsweetening an infected cider?

I just opened up a two and a half month old tart cherry cider only to find a decent pellicle on top. It still smells pretty good (like tart cherry's).

It fermented down to .998 and was extremely dry and tart when I tasted it a couple months ago. My plan was to bottle it with a combination of corn sugar to carbonate and lactose to sweeten. I just wanted to take the edge off of the tartness.

Anyway, now that I suspect infection, is there anything I can do to sweeten it? Is metabi and/or Pasteurization my only option?

Regardless of the surprise organisms in there (brett, lacto, something else?), it's extremely difficult to bottle condition and sweeten. With the surprise, it's perhaps risky to even try a champagne method of carbonating, disgorging, and adding dosage.

You could use kmeta and sorbate, as in wines, to allow backsweetening, but that wouldn't allow for carbonation. Or, you could carbonate, keep it dry, and just add sugar syrup to each glass at serving time. Without a keg, getting both at the same time would be challenging.

Also, I would not assume the lactose, if added, would not also be fermented.

Thanks.

I'm thinking that I might just put it in a carboy and taste it again in a couple months. If it tastes alright (not vinegar) I'll probably bottle it as is and mix it with apple juice or sugar as I drink it (like you suggest) or blend it with a sour that isn't quite sour enough. My research shows that your suggestion about the lactose is accurate. That was one of the things I was worried about.

I can't help but chuckle at the fact that a couple of years ago, I would have freaked out upon seeing the pellicle, immediately dumped it and scrapped the fermenter. Now, I find myself kind of excited about the possibility of a soured or brett infused cider.