Food storage
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Food storage is both a traditional domestic skill and is important industrially. Food is stored by almost every human society and by many animals. Storing of food has several main purposes:
For food preservation see Food preservation
- preparation for periods of scarcity or famine.
- taking advantage of short term surplus of food as at harvest time.
- enabling a better balanced diet throughout the year.
- preparing for special events and celebrations.
- planning for catatrophe or emergency.
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Domestic food storage
Storage facilities
Almost all food storage requires cool and dry conditions. In many countries this is provided by a refrigerator or larder.
Root cellars and spring houses are also effective in temperate climates where the average ground temperature several feet below the surface is less than 15°C (60F°). A traditional root cellar is a masonry (usually concrete) storage area (often in a basement) with roof and house-side wall, if any, insulated, and outside walls insulated to the depth at which ground temperature has no seasonal changes. Farmers improvise large root cellars by bulldozing a 1-1.5M cut, wrapping produce in plastic sheets and placing them in the cut, and bulldozing 1 to 1.5M of cold subsurface dirt over them.
Spring houses are very similar to root cellars except that the cold water from a natural spring is used to cool a bucket (usually metal) or storage area.
Ice houses are used in some parts of the world to store ice for use in Food preservation
Grain
Grain is stored in rigid sealed containers to prevent ingress of moisture or attack by vermin. For domestic quantities metal cans are used (in the USA the smallest practical grain storage uses closed-top #10 metal cans).
Storage in grain sacks is not effective. Mold and pests destroy a 25kg cloth sack of grain in a year — even if stored off the ground in a dry area. On the ground or damp concrete, the time is as little as three days, and the grain might have to be dried before it can be milled. Food stored under unsuitable conditions should not be purchased or used because of risk of spoilage.
Fruit
Many hard fruits such as Apples and Pears can be wrapped in paper and stored in boxes in a cool dark cellar for many months. Cooking varieties keep better than eating varieties and harder more acid varieties keep better than softwer sweeter varieties.
Soft fruit can only be stored for long periods if preserved (see Food preservation)
Meat
Un preserved meat has only a relatively short life in storage. Pork should be eaten within one day but Beef and Venison improve with up to 5 days storage in a cold room.
Fish and shellfish
It is unsafe to store fish or shellfish without preservation. Fresh shellfish and whitefish should be eaten within a few hours of harvesting
Use of Stored food
Guidance for surviving emergency conditions in many parts of the world recommend acquiring a limited range of grains (usually corn, wheat and beans supplemented with oil, dried milk, and vitamins) and then preparing them in simple ways for long-term survival. This may not practical because of appetite exhaustion. An unvarying diet of staples prepared in the same way causes most people to eat less, and roughly 90 days after beginning such a diet, people may begin to starve to death from a lack of desire to eat. Garden-grown fruits and vegetables, freeze-dried, canned, and fresh-baked foods are essential supplements to such a program.
A special virtue of home stored foods is their low cost. Costs of dry bulk foods (before preparation) are often less than 1/4 of convenience and fresh foods purchased at supermarkets.
Commercial food storage
Grain and beans are stored in tall grain elevators, almost always at a rail head near the point of production. The grain is shipped to a final user in hopper cars. In the former Soviet Union, where harvest was poorly controlled, grain was often irradiated at the point of production to suppress mold and insects. In the U.S., threshing and drying is performed in the field, and transport is nearly sterile and in large containers that effectively suppress pest access, so irradiation is not required. At any given time, the U.S. usually has about two weeks of stored grains.
Fresh fruits and vegetables are either packed in plastic cups in cardboard boxes for fresh premium markets, or placed in large plastic tubs for sauce and soup processors. Fruits and vegetables are usually refrigerated at the earliest possible moment, and even so have a shelf life of two weeks or less.
There is a thriving but small market in bulk vegetables and convenience foods for campers.
In the USA meat animals are usually transported live, slaughtered at a major distribution point, hung and transported for two days to a week in refrigerated rail cars, and then butchered and sold locally. Before refrigerated rail cars, meat had to be transported live, and this placed its cost so high that only farmers and the wealthy could afford it every day. In Europe much meat is transported live and slaughtered close to the point of sale. In much of Africa and Asia most meat is for local populations is reared , slaughtered and eaten locally which is believed to be much less stressful for the animals involved and requires very little meat storage capacity. In Australia and New Zealand where a large proportion of meat production is for export meat is stored in very large freezer plants before being shipped overseas in freezer ships.