There are a variety of insects that can infest flour and grains and grain
products. We introduced some with some ethnic-looking basmati rice in a
jute bag.
The ones we have that are a problem are very tiny beetles that can crawl
right through spaces in 'tight' lids and so forth. They appear here in
Minnesota toward the end of summer when everyday is warm and humid and just
to the liking of the beetles. The solution is simple - deprive them of air.
The way to do that is to use carbon dioxide (CO2) to displace the air from
all the containers where you store flour and grain products. You need
jars, bins, or whatever that are tight at the bottom and a bit LOOSE at the
top. Get some dry ice from some source (bait shops are good for this or
try the yellow pages). Dry ice is solid carbon dioxide that will turmoil
to the heavy gas as it vanishes. Just put dry ice in all your containers.
Wrap it in some newspaper or else it will create frost. We have one large
flour bin (ca.3' x 2' x 2') where we store most of our flour for daily use.
I use a hunk of dry ice in there about the size of a big bar of laundry
soap. I put walnut sized pieces in small plastic containers of grain, etc.
The carbon dioxide is much heavier than air, so it flows to the bottom and
pushes the air up and out. No oxygen for the critters, so they die. Not
only that, in flour bags they retreat to the bottom corners and seams of
the bags to die, so they even leave the flour free of little buggers.
IMPORTANT! Do not EVER do this with a sealed container. A tightly sealed
jar will explode as the carbon dioxide pressure builds up. Be sure that
you have a leak at the TOP of the container. The carbon dioxide is
completely non toxic and leaves no residues whatsoever. If you can't find
dry ice, a bowl of baking soda with some diluted vinegar poured into it
carefully will do the same job. In a large container, you can check the
level of carbon dioxide with a soap bubble. The bubble will rest on top of
the invisible carbon dioxide filling the bottom of the container.
AGAIN - NO SEALED CONTAINERS! Also, be sure there is ordinary adequate
ventilation so the carbon dioxide doesn't migrate to a low spot in the
house. Most houses are leaky enough that such is not an ordinary danger,
but if you have a fire pit or some such depression, and no breeze at all,
the CO2 could collect there. You want the CO2 in the four and grain
containers.
Ron Parker (mailto:rbparker@henning.cfa.org)
Fiber Home (alpha vers.) http://www.angelfire.com/mn/FiberHome
south of Henning, Minnesota, USA at historic Sammen Sheep Farm