Geoscience Reference
In-Depth Information
If frost crystals are present on the surface of the dry ice, wipe clean with a cloth to prevent
the introduction of extra moisture into your food. Press the lid down gently, leaving a small gap
for air to escape. After 20 to 30 minutes, check to see whether the dry ice has fully evaporated.
If it has, seal the container. For the bottom-of-the-bucket method, seal the container after 20 to
30 minutes. If the lid pops off, or the container bulges, crack the lid open and try again in 5
minutes.
Caution:
A bulging container may burst.
Note:
For the dry-ice method to be effective for the long term, the container must be air-
tight.
Table 3-2. Basic Dry-Ice Treatment Guide
Container size Food quantity (lbs.)
Dry ice required (oz.)
Expansion space
Metal containers
no. 10 can
3-5½
1
¼˝
5 gal.
15-35
2-3
½˝
25-30 gals.
100
8
½˝
Plastic containers
1 gal. 3½-7 1 ¼˝
4 gal. 13-30 4 ½˝
5 gal. 15-35 4 ½˝
(Source: Stevens, Making the Best of Basics: Family Preparedness Handbook, 1997)
Vacuum Packaging
Vacuum packaging removes the oxygen and excess moisture from dry foods, killing critters and
extending shelf life. A simple, but only partially effective, vacuum-packing method is to pack
food in plastic bags and suck as much air out of the bags with a soda straw as you can prior to
sealing the bags. Heat sealers are the most effective vapor barrier, with zip locks a second best.
Moderately priced electric and hand-operated vacuum pumps are available for vacuum-packing
goods in jars, cans, and bags for long-term storage.
Mousetraps and Rat Poison
Don't forget to buy a bunch of mousetraps and Decon (or similar rat poison) to protect your
food stores. The mousetraps that work best for me are the traps with a food-scented yellow-
plastic bait paddle. I find that mice can't resist the trap when I spread a little peanut butter on
its bait paddle, and the wide paddles are so easily tripped that mice almost never escape with
the bait. Be careful if you use poison, because it can also poison children, and if your cat eats a
poisoned mouse, your cat will be poisoned too. We personally rely upon traps, and don't use
