Assuming the fruit drink was made with fresh fruit, the wire looks like it could be the remnants of a plastic-over-metal twist seal type of thing. If it is, one wonders what happened the plastic.

I had a similar experience many years ago, eating a side salad, except it was a much bigger and sturdier all-metal twist tag, appeared to be the fastening of a catering size bag of something, and I first discovered it when biting down. Luckily it didn't do any damage, but it certainly was capable of wrecking my mouth/tongue.