energizer cider

It just keeps going.
I had a gallon of cider that noone was drinking so i decided to pitch some yeast in it and see what happens.
It was only about 1.040 on my refracrometer so i added a loose cup of brown sugar witch brought it up to about 1.054. and a put it in a glass jug with an airlock.
I had a pack of nottingham and because i didnt have any use for a partial pack i pitched it all.
Now THREE weeks later its still bubbling away. I mean like every three or four seconds. My 5 gallon wine batches dont do this after one week. I have made several batches of wine and a few batches of beer and they all seem to peter out after a few days.
What is the yeast eating? The sugar should have been gone long ago. I can see a few days extra for dissolved co2 working its way out but this is ridiculous .
Oh well its only a gallon that was going to waste anyway. I am gonna stop it this weekend one way or another. Funny thing is i used the nottingham for its lower attenuation.

 

The thing with cider/apple juice is that it is made up almost entirely of simple sugars, so the attenuation level of the yeast actually means very little. If you taste the cider right now, you will probably note that it tastes very dry and boozy. To get that "draft" cider taste, you really have to either stop fermentation when it has reached your desired sweetness, or backsweeten it with apple juice concentrate/other sugars after it has completely fermented and cold crash the cider so that the new sugars you have introduced don't ferment out too (because they will). Good luck with this. Cider is always fun, but even in its ease and simplicity it requires a bit of attention!

 

I figured I would have to backsweeten it. I just expected it to be done way before now.
Thanks for the reply