Black Cherry Cider and Oxidation?

Hi, folks. Been playing around with cider recipes for awhile now and really love them. Made Dead Squirrels Turbo Cider recipe with variations with Caramel Apple, Cinnamon Vannilla, etc.

I made a basic 5% ABV cider or so with just using basic preservative free juice and nottingham ale yeast. Turned out nice and sweetened a bit with Lactose.

I have just made the same type of recipe but this time I also added concentrated Black Cherry flavoring. Organic, no chemicals, etc.

It fermented well. I racked it into a secondary and added gelatin finings for clearing. I have had it in the secondary for about a week now. It is a 5 gallon glass carboy and there is about 4 gallons of cider in there. It is developing white patches with bubbles in them throughout the top of the cider. They are not "mold" like, just white bubbly film that when you move the cider around a bit they dissolve again only to form again later.

Thoughts? Should I be concerned?

It sounds like "yeast clumpies" really. Doesn't sound like an infection or anything. You probably do have too much headspace, though. Wines and ciders should have almost no headspace after fermentation is about over. There isn't enough fermenting going on to have co2 blanket the headspace.

If you have a 3 gallon and 1 gallon carboy available, I'd rack into them to minimize the headspace and add 1 crushed campden tablet per gallon (dissolved in a little water).

Thanks, Lorena. Another forum suggested that malolactic fermentation was going on, so I would agree with ya. My 3 is being occupied with wine but I have several 1 gallon ones that I can split this up in.