After ensuring you have enough water, which is usually like 2 litres a day (if you're not doing heavy physical work - keep 1 or 2 litre bottles handy), you need to have food for energy. In Japan, you're going to be able to purchase a variety of canned, dried, and preserved foods, some of which aren't available or very common in North America. One more thing, many households will have a small portable, single burner stove that works off of butane canisters. These stoves are often used for hot pot or nabe. Even if the power and gas is out, they will be able to cook or boil water on this.
The Tokyo Metropolitan Government has a pretty good PDF for Emergency Preparedness here.
Canned Foods / Biscuits / Ready Foods
Canned foods are heavy, but are ready to eat, and often have tops that can be pulled off with a ring. Canned soups are not popular in Japan, but there are all sorts of pickled vegetables, and canned meat available. When I'm talking about canned meat, I'm not talking just canned ham or chicken or SPAM. In Japan, the canned foods trend towards more gourmet selections ranging from teriyaki chicken, braized pork belly, soy grilled mackeral or tuna, etc. They can be a delicious accompaniment to white rice or a picnic. You can find video reviews of some of this stuff on Youtube.
|This is just a small selection of canned or jarred goods at a convenience store. Nice big selection of CalorieMate at the top.|
|These biscuits are like a bit of a meal replacement. Think Clif Bars, but a bit more. I'm only okay on these things, but hard working office workers seem to use these. These things last months and months and are found in all convenience stores.|
|Potato chips - not balanced, but a real morale booster.|
|Bourbon Campan biscuits in a can. These little bite-sized biscuits mixed with sugar blocks are good for 5 years and provide quick energy when needed.|
|Canned bread. This stuff lasts a year and comes in many flavours from plain, strawberry, raisin, chocolate, etc. They are pretty good and could be a nice treat or change.|
There are many varieties of retort packaged sauces / curry which would go well with some packaged pre-cooked rice that you can buy at the supermarket. The pre-cooked white rice is like the Uncle Bens rice that nukes in a minute and a half here, but it often comes in sealed trays (like in a JSDF MRE). You don't need to add water, and just heat the sauce and mix with the rice and any other ingredients you would add.
|Ready to use curry pouches for everyday meals, but they are also good in emergencies.|
Everyone is going to have some rice or noodles handy. These usually require longer cooking times though, so fuel becomes important. But freeze-dried is a nice in-between that saves on cooking while remaining very light and good for long-term storage. In North America, and Japan, you can buy freeze-dried camping meals that can last years. You need to boil water and hydrate the food right in their retort / foil pouches for 10 to 15 minutes in most cases, but they can provide a tasty meal. In Japan, some more common types are freeze-dried rice dishes that can be used for a regular meal, or be good for 5 or 6 years on the shelf. Of course, even if you don't have boiling water, you can use room temperature water to rehydrate, but it take like 3 times as long. Same goes for instant noodles.
|This freeze-dried pouch is like a traditional japanese rice mixed with vegetables.|
|Dehydrated rice balls / onigiri. You add water, then wait. The bag is a shaped pocket by which you can make a rice ball by applying a bit of pressure. Instant rice balls... wow.|
This is something close to my own heart. Instant noodles are everywhere in Japan and are very popular food items. Cup or bowl noodles are staples in the convenience store / konbini. They will even provide hot water for them on request. A few packs of noodles or cup of noodles are always on hand and they last half a year to a year for the regular stuff. There are many different flavours and varieties. The curry noodles are always really tasty too and the new anime Laid Back Camp aka Yuru Camp even has the lead protagonist enjoying curry cup noodles in the first episode.
|The instant noodle - the amazing food invention of the 20th century? Better than sliced bread?|
|Curry Udon Noodles|
|Lots of different kinds of instant noodles.|
|Cheese Curry Noodles - yummy.|
|Curry noodle cup. The broths tend to be thicker due to the curry mix. Very satisfying.|
|Nissin 3 year shelf-life emergency canned cup noodle. My review of it can be found here: Nissin Cup Noodle Canned Emergency / Survival Ration Review|
More Instant Ramen Posts and Japanese Pop Culture.