Its the glass. I've had it for a little while now and its almost finished but its still pretty much the same as when I bought it. Its 0mg too.
I buy all my juice 0mg now regardless of where I get it. It keeps much better and also if I don't like it then I can pass it on here.

I think what I'm finding weird is the sweetness. Hard to explain but its kind of like sprinkling something thats meant to be savoury with a
heap of artificial sweetener