I've noticed that if you make food from scratch, there's some pretty hefty energy requirements that go into producing it. I've been a little worried about these - in some cases, it seems that the energy you'd get from eating the food only barely covers the cost of making it from scratch, or worse, is actually less than the made-from-scratch energy investment.
I'm going to work out the math once I'm back ingame, but if my hunches are correct, then only the most high-end food is worth making from scratch, and it may be more efficient, energy-wise to eat raw pork straight off the piggy than it is to cook it into a recipe first. Watch this space.