You will probably not have a huge appetite the first couple of days to a week, then it will hit you with a vengeance. Keep that in mind when you are out the first few days, and don’t gauge the trip by that.
With that being said, your best option, if you are pre-packing some meals is to pack AT LEAST 2 servings for each meal, if not more. A lot of people carry a few ramens, and break some up in each meal as an added filler.
The most difficult thing about pre-packing food is getting tired of what you pack. Keep a wide variety, try it all out before you go, and keep in mind that you may end up picking up a few things along the way and discarding some of your pre-packaged meals.
It may be a good idea to double-bag the zip-locks, as well, or get some super-sturdy zip-locks (freezer bags, etc). They are VERY easy to tear.
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