Not that I am a tinfoil hat wearing nutjob, but I believe in preparing for all possibilities in this life. I have previously posted on emergency kits, and I wanted to expand on this for a little long term planning. Say avian flu hits and the high mortality rate of the flu shuts the world down for more than a few weeks (economic depression much more likely but still). There would be a run on supermarkets, and electricity might be a problem if power companies lose workers. So what are you going to do for food? The human adult needs about 60 grams of protein a day and at least 1500 calories. Well if you were a prepared individual, you might have a garden with some veggies and lots of canned food. What kind of canned food?
1. Peanut Butter - This lasts for 2 years or so, has tons of calories fat & protein, and tastes good. Survival food that tastes good is awesome!
2. Beef Jerkey - I have no clue when this goes bad as long as it is sealed. It's beef jerkey, even regular beef jerkey tastes weird.
3. Tuna - Canned tunafish can last 4-6 years. There are typically 30 grams of protein in a can of tuna, and tuna has tons of those good omegas the adverts always discuss.
4. Spam - I am dead serious. Spam got the British through World War 2, so it can work for me. A good thing about Spam: it never goes bad. As long as it is sealed, it stays preserved. Awesome!
As far as starches/carb source, I'd get a big bag of good ol' white rice and store it in the burpable tupperware containters. If you don't mind simple carbs for a while, stick to honey and sugar. Honey never goes bad, even honey found in Egyptian tombs could be used today. Canned vegetables can last months if stored in a cool dry place, and if crap hits the fan only for a few weeks but you have to take in your relatives, you'll be set with several weeks of provisions stored.
As an addendum to this list of long term food, you might want to pack some 'barter goods'. Say the housing bubble pops, our economy tanks, and a global depression kicks in. Maybe you keep your job, maybe you don't. What are a few things that every person considers a basic need in life that they would trade you for that? Well, let's step back in time to a tv social test that answered my question. When Survivor on CBS first aired, it was not as hokey and fake. The survivors were allowed 1 luxury item. A dildo brought the Bible (it's an island), another dildo brought a cd player (it's an island), and the 72 year old former Marine brought the one item that everyone was asking to use: a combination razor/toothbrush. If you find the shit has hit the fan and you're still on this planet, thank your lucky stars to be alive, and get your hands on some razors, candles, toothbrushes and soap. These items will be worth quite a bit to folks; add to that cigarettes. Look at prisons, cigarettes act as a substitute for cash. Not to leave out the ladies, think about storing up some tampons/pads; great for deep cuts in case of an emergency and they are a basic need. Think about what you enjoy as a luxury, and what you need for basic health and cleanliness.
In any survival situation, the biggest factor is mental attitude. If you have a strong will to live, there are few things that can hold you down. I'll go back to wearing my tinfoil hat now.