http://www.astray.com/recipes/?show=Starbucks% 20frappuccino
This is a "clone "recipe . But it's an American site so I would say the C means Cup measurements....the 2% milk ..skimmed or semi skimmed milk. Pectin you can get here..it's what they use to set jam.
Half a cup is four fluid ounces liquid measure.
Quarter of a cup is four tablespoons dry measure.
Hope this helps.