What's in that food you're eating?

So, having recently kicked my gym-bunny habit into full gear ... again ... for the third time now ... I started looking more closely at what I eat. I've always considered low-fat yoghurt to be one of the better things you can eat for a snack. But, after being told (you need to sign up to see this page--it's free, so don't worry--and it's page 7 on week 4) that I need to consume at least 400g of protein a day, I wanted to see how much of that protein I'm getting from my yoghurt.

Well, here's the breakdown of what's in my yoghurt:
Calories: 210
Serving size: 1 container (227 grams ... keep a note of this!)
Total fat: 2.5 grams
Cholesterol: 0.01 g
Sodium: 0.105 g
Potassium: 0.300 g
Total carbs: 41 g
Protein: 7g

Wow. 7g? That'll be about 57 yoghurts I'll need to eat. Yikes.

After looking at all the nutrients in the yoghurt, I wondered about something. Do all those numbers add up to the total weight of the yoghurt in the container?

Not even close.

It seems that there is 176.085 grams of ... stuff ... in my yoghurt. Out of 227. Only 50.915 grams of the yoghurt is really accounted for, nutritionally.

So, that left me to wondering... what the hell ELSE is in my yoghurt!?