brian k, for 3 season, ie, not snow or too cold, no problem packing in 5-7 days of food into a 33 liter pack, that's about 2100 cubic inches, not counting outside pockets (sides/back). As noted above, you can't ignore your body weight + your daily mileage when figuring your food requirements. I'm average I'd guess in mileage, 8,9 hours a day is fine with me for hiking time.
No commercial food except some dried veggies/raisins/dates, almost all dried in dehydrator.
Fat is olive oil carried in a bottle outside pack.
Breakfast: oatmeal, flattened style, dried apples, olive oil. Can add dried milk if you want more protein.
snacks: dates, raisins, pemmican, home made, dried fatty meat.
lunch: dried homemade heavy whole wheat bread, I cut it into small slices then dry. Salami is a good topping, or dried humus mix, whatever. the dried bread is the bulkiest thing I bring, if I could make that take less room, maybe some homemade flat bread, 7 days would probably be doable in that that pack in winter/rainy times.
Dinner: dried cooked brown rice, dried sliced/diced potatoes. brined, then dried then chopped meat. Dried veggies.
All the foods are stored in bulk food bags, so there's no waste of space. Cooking is boil then put pot in cozy until rehydration is complete.
last trip I brought enough for 7 days but only went for 5 days due to a miscalculation and some glitches, 33 liter pack, myog, 24 pounds when I walked out the door, with I think 1 pint or so of water. Not sul, or ul, just light in terms of baseweight.
Olive oil and pemmican are about the densest energy/nutrition sources in existence, and way better for your body than sugary stuff, and weigh the least per calorie than anything out there.
I have to admit I scratch my head when I see these larger packs, I tried making one initially that was about 45 or 50 liters and realized it would be 1/3 empty even when all my stuff is in it, following what must be an old template from thru-hiker. Winter and bear canister I could see needing more room, 40 or 50 liters inner capacity.
I got a cheap fanless circular stacking tray dehydrator, used, and, after some testing, realized it was drying at around 140 degrees, which cooks, not dries, the food, I added in a hacked computer case fan (92mm) plus power supply (ac->dc 5v, 1000ma, the fan is 12 v so using a 5 v adapter slows the fan down to the right speed for the temp desired) brick on top which drops the temp to about 120 degrees, which is ideal. No need to spend a lot on a high end machine, but the high end ones have the built in fans and temp controls, but they eat a LOT of power compared to what I use. Total cost, about 8 dollars I think, give or take, I had the case fan already. Works great, not as fast, but fine. A thermoter is needed if you don't have a thermostat operated dehydrator so you can know what temp it is drying at.
If I had a yard with full sun I'd use a solar dehydrator, which are easy to make, and run off solar thermal energy, of course, that would be awesome, but I don't have a yard.