I know you already went shopping but in the future the three things I carry that are the best for a nutrition to weight to taste ratio are homemade oatmeal (oatmeal, flax meal, hemp seed) sweetened with natural stevia. Stevia is best 1 teaspoon= 1/3 cup sugar. no weight and no room in pack. second and I kid you not is Quinoa. It is mutifunctional, tastes great, is a whole grain, and is natures pure protein. Bring a dried spice mix and you are set...also easy and quick to cook. http://nutritiondata.self.com/facts/cereal-grains-and-pasta/10352/2
The best part of the two above is they are full of fiber for fullness. Lastly, I always bring those to go packets of ice tea. I hear you on the taste but I have learned the key is to dilute it more 1 packet for 750ml to a liter.
I also bring smoked meat, dried fruit mostly cranberries and almonds as they can be added to the oatmeal or quinoa
also bring multigrain tortillas and peanutbutter...tortillas are flat light and can be stuffed anywhere unlike bread.
I do use the freeze dried stuff but it is so high in sodium I really can't eat that stuff anymore
have fun and I expect pics