But is one really better than the other? I did some research, and found that the answer is far from clear cut.
Concentrates start as fresh fruit juice, but some of the water is evaporated. The resulting concentrated juice takes up less space, and uses less energy to transport. If you're shipping orange juice from (let's say) Brazil to Europe, that seems a pretty important consideration. Eventually, when the concentrate arrives at the juice factory, the missing water is added back in and the juice is delivered to the shops.
Juice marked "not from concentrate" doesn't go through this process. This makes it sound fresher, because it's squeezed closer to home. But it does mean that the whole fruit has travelled further, as opposed to just the juice from the fruit - which means more Food Miles.
In terms of nutrients, the government's "five a day" campaign makes no distinction between types of juice - one glass of juice equals one portion of fruit.
Which gives something of a dilemma. Unprocessed and fresh, or fewer food miles: which do you go for?