I have been making cider for over a year now. I usually start them, let them go a week or so and drink it.
When I first started making cider I made a 5 gallon batch. That was over a year ago. I wanted to age it and just let it chill.
To be fair, because it was over the period of a year, probably almost 1.3 or 1.4 years ago there were times when I forgot to check the airlock. About twice the airlock didnt run completely dry, but it did get low enough that it was no longer locked. This only happened for at most a couple days.
I noticed this sort of skin on top of it. This happened in the primary (I had it in the primary a really long time) so I transferred it, and it was clear in the secondary for a while. Recently (and it seems like after the airlock ran low) it developed this skin or film on top.
Now I know that when cider comes in contact with air, it can have a reaction and develop a sort of skin. I am hoping that is what this is here, however I've never seen it before. So I wanted to ask the experts, is my batch infected?