Information on how to preserve grains with
Oxygen absorbers may be easier to use for grain storage,
but I prefer using dry
ice (frozen carbon dioxide)
to store my grains. The dry ice method is much cheaper, and because
it is a fumigant it actively kills the insects that may already be in the
NOTE: The eggs of the insects are in all wheat and
under the proper circumstances (time, humidity and warmth) they will
hatch. They bore into the wheat kernel from end to end, eating the center
of the kernel. The remaining outer part will begin to crumble
and form a fine powder. You can't glance into a full bucket of wheat
and tell if there are bugs in it unless the problem is severe.
The best way to avoid an insect infestation is to purchase from suppliers
who are clean and have a high quality products. This
will mean the products you purchase will be less likely to have bugs
When you buy grains take a close look to be sure that
insect are not visable. Don't shake the grains because most adult insects
will be visible in the top couple of inches of the grains and shaking
the grains could mix them further sown into the container where they
will be less visable. If the grains you pruchased do have bugs
take them back and replace them.
The good news about dry ice is that it takes as little
as 10% carbon dioxide over a fairly short period of time to kill
insects. At 10% the insects would be killed in about a month. The higher
the concentration of carbon dioxide, the faster it kills the insects.
The time it actually takes can be reduced to hours rather than weeks
at close to 100% concentrations. It is easier to get enough carbon dioxide
into a container of grains to kill the insects than it is to get 100%
of the oxygen out, and then keep it out.
Important Information !
All you need is a bucket with a lid that will make an airtight
seal and a little dry ice. Dry ice is a solid and looks much like regular
ice - except that it's -110 degrees F. below zero (-78.5C).
ICE SAFETY: Never handle dry ice with your bare hands, it
can cause severe burns! Always use gloves or tongs. If using large
amounts of dry ice indoors or in a closed area allow for plenty of
ventilation. As it sublimates the dry ice releases it's carbon dioxide
which living creatures, like us, shouldn't breath. Do not store Dry
Ice in an air-tight container without proper ventilation, the carbon
dioxide gas will cause any airtight container to explode.
IMPORTANT NOTE: When you store your food in plastic pails, make sure
they are food-grade. Other
plastics are made with chemicals that are not good for your health and
leech out into your stored food.
Dry ice is frozen carbon dioxide. Carbon dioxide is a fairly harmless
long as it doesn't
all the oxygen in the air you are breathing.
Unless you will be packaging your grains in a very small airtight room,
you should have nothing
to worry about. But be aware that under unusual circumstances carbon dioxide
can be deadly. I've had several people send me emails about a person
who actually died while using dry ice in a haunted house at Halloween.
Apparently, the person was under a card table covered with a blanket,
using water and dry ice to make a thick cloud. They said it didn't
take an airtight closet to kill
him. Counter this with the news story of the woman who put a
whole tub of dry ice under her husband's bed trying to 'do him in.' When
was arrested for attempted murder she said, "I don't understand, it worked
We breath in air containing oxygen and breath out air containing carbon
dioxide. There's carbon dioxide in our houses all the time simply because
are breathing. I've heard people say you have to do this outside or the
fumes will get you. That's the reason I'm making such a big deal out of
this. Just use common sense.
Carbon dioxide, in it's frozen form, is highly compressed compared to it's
gaseous state. A pound of it contains enough carbon dioxide gas to make
cubic feet of carbon dioxide gas. A six gallon bucket contains 1.46 cubic
feet of space. Fill the bucket full of beans or wheat and you have about
0.48 cubic feet of air left in the container surrounding your food. So,
you use twice as much dry ice as you actually need to displace the air
the bucket, you will need about .06 lbs, or right at one ounce of dry ice.
Heck, be generous and put in two ounces of dry ice if you like. The smallest
amount of dry ice I can purchase is 5 lbs which costs me $5.00. At even
ounces per bucket, that's enough dry ice to take care of preserving 40
buckets of food, more than I have ever done at one time. At two ounces
bucket, this is enough dry ice to push the air out of a six gallon bucket
four times. You want a little bit of overkill or redundancy here as it's
always better to overdo this than under-do it and end up with oxygen left
Where To Get Dry Ice.
I get all my dry ice from a welding supply shop.
also often available at ice cream places and chemical supply houses.
you get your dry ice you need to bring your own container to put it in.
There is one thing you really need to watch for if you are going to be
dry ice to preserve your foods. You must prevent water vapor from freezing
on the outside of the dry ice. This moisture would later melt off the
ice in the bottom of your bucket and increase the water content of your
grains. As you don't often have a lot of room to play with as far
water content is concerned, it is important to ensure you don't add any
moisture to your product with your dry ice. The dry ice you buy from
store should be water free, and that's the way you want to keep it.
Dry ice is always giving off carbon dioxide gas, so it's relatively easy
keep the water moisture from it. Just be sure you don't put it into a
container that breaths, like a paper bag or cardboard box. I use a
Tupperware container which has its own lid. This container is just right
because its lid is tight enough to keep water vapor from the ambient
out, but loose enough to permit the carbon dioxide gas to escape as it
sublimates. By the time you get it home, there will be a thick layer
frost on the outside of the container - exactly where you want it, on
outside - not the inside. The inside will be moisture free because of
continually escaping carbon dioxide gas.
There was one time I purchased dry ice which had a bunch of water crystals
mixed in with it. You can tell this because there is a white powder mixed
with the dry ice cubes. Ice is just a tiny bit whiter than the light
dry ice. You can put a teaspoon or two of this powder in a bowl, wrap
plastic wrap around the top, and wait for it to turn into a gas. If it's
indeed water, when it melts you will get a little liquid in the bottom
your bowl. If it was dry ice, the bowl will be dry.
You can use dry ice with all grains. At
home I use dry ice to preserve all my seeds, and all my grains
Before you ever buy it, plan on having your packing operation complete
hours after you've purchased the dry ice. Otherwise, it may 'sublimate'
on you until it's gone whether you are finished packing your buckets
So, how do you do it?
Materials Needed: A food scale, a measuring cup, dry ice,
the grains you are
planning on preserving, and storage containers.
The process: Zero your food scale with the measuring cup sitting on
top of it. Open the container with your dry ice in it
and take out about 1/3 cup
and measure it. Depending on how your dry ice cubes are shaped, you
have about 2 ounces. (Remember, if you want to be stingy, one ounce
the trick, that's 28.5 grams.) Pour this into the bottom of the bucket
neat little pile and place a paper towel over the top. Why the paper
It keeps the dry ice away from the food, not that it's that important.
place your grains inside the bucket, filling the bucket up to within
inch of the top. Set the lid lightly on top and wait. Recently, I have
sealing the lid all the way around except for one small side.
You DO NOT want to seal the lid completely as the carbon dioxide and
air must have a place to escape. If the lid makes an airtight seal,
expanding carbon dioxide inside the bucket will continue to increase
pressure until something gives - either the lid will pop off or the
will split. Either way you are going to have food all over the place
this thing goes off. How do you know when all the dry ice is gone and
safe to seal the lid? Simply pick up the bucket and feel the bottom.
is still icy cold there's still dry ice in the bottom. You may need
to be a
little patient here. My experience has been that it takes 1 to 2 hours
all the dry ice to change into a gas. I've had others E-mail me saying
had to wait around for 5-6 hours! So you may wish to plan in a certain
amount of time for this in case it takes a while. You want to seal
just as soon as this has happened, however, because if you don't, air
start circulating back into the container.
After 15 or 20 minutes, I start checking my buckets, and then recheck
them every ten minutes or so. After you seal your buckets, it's always
idea to keep an eye on the lids for the next hour or so. The lids will
bulging up if you sealed them a bit prematurely. If this happens, use
bucket lid remover to crack open the lid on one side to let the excess
escape, then seal the lid back down. I'm not sure why, as my logical
tells me it should be otherwise, but over the next several days there
usually be a small vacuum created inside the bucket and the side will
a little bit. Don't concern yourself with this. Your bucket will store