I have an interest in preserving true masa corn from oxaca mexico for tortillas - most corn here is genetically altered and it is filtering into mexico...

my techinique (since corn will turn to dust from inherent bugs) was to wash freezer safe jars thoroughly, then sterilize them in the dishwasher including "heat dry"; then I placed the "dry corn" in the very dry hot jars and put them in a preheated oven at 170 degrees for 20 minutes (without lids)to remove as much moisture as possible without hurting the corn. I removed the jars, put the lids on immediately.

I let the jars cool down, then slowly cool in the garage (its winter), then put them in the freezer.

This is the absolutely safest way I could come up with - corn is a little tricky because of its seed bulk.

here is another post from this forum:

Remy posted: "If you really want to keep seeds indefinitely, you can put them in an air tight container in a freezer. There are a few things you must know first. The seeds must be really dry. Trying to store them with not enough moisture gone, will kill them. Also, you must let the container come to room temp before opening or you will kill the seed. If you plan on retrieving seeds from the freezer once a year, this is no problem."