Geoscience Reference
In-Depth Information
ging, leaking, or “spits at you” when you first pierce the can with an opener, get rid of it! Den-
ted cans are prone to corrosion failure long before their undamaged twins, so don't waste your
money on bargain-basement canned foods that are dented or close to their expiration date.
Root Cellars and Other Cold Storage
Light and heat are the enemies of most stored food. A root cellar is the traditional way of stor-
ing fresh foods for use throughout the winter. Even canned foods last far longer when stored at
lower temperatures. The shelf life of canned foods is doubled for each 20˚F decrease in storage
temperature (Stevens 1997, 41). Ideal storage temperatures for most nonfrozen foods are 35˚F
to 40˚F. Most fruits and vegetables shrivel rapidly unless they are kept in a moist environment,
so either store them in cartons layered with moist sawdust, burlap, sphagnum moss, and so on,
or keep cold-storage areas moist by spraying water on the floor at regular intervals. Too much
moisture causes rot, so make sure that moisture is not condensing on the ceiling and produce.
Root cellars offer a means of storing “live” food for use throughout the winter. Unlike fresh
fruits and vegetables, dry fruits, vegetables, seeds, nuts, and grains must be kept as dry as pos-
sible, so they should be kept in sealed containers or in a separate, dry, cold-storage area.
Freezing is simple, quick, and easy, but has higher energy costs than other preservation
methods and requires a steady source of power (or an extremely cold winter). Deep freezers
can keep food for years, but the regular frost-free home freezer is only good for about six
months. Propane refrigerators and freezers are a good option in remote locations, in solar
homes to take the load off solar panels, and where power outages are frequent.
You can build an efficient root cellar in the basement of your house, in the outside stairway
to your basement, in a pit outside, or aboveground in an insulated structure. The keys to suc-
cess are temperature and moisture control, and effectively keeping critters away from your
stores.
A handy basement root cellar can be made by walling off an unheated corner of the base-
ment with insulated stud walls (see
fig. 3-1
). Building the walls on a double runner of pressure-
treated wood sills allows for wetting down the floor without rotting the walls. If possible, pick
a north wall for one of the walls of the root cellar. A window or some type of screened ventila-
tion pipe is required to vent stale air and allow cooler air into the root cellar. Do not insulate the
exterior walls. You are using the thermal mass of the earth (at about 55˚F) and the colder north-
wall outside temperatures to help keep your root cellar optimally cold. Place a reliable thermo-
meter inside the root cellar and one outside the window or vent. Open and close the vent/win-
