CO2 Storage I have been reading here and have had discussions with locals that store foods such as grains, flour, rice, dried corn, etc. by placing the foods in a bucket, jar, etc. and placing some "Dry Ice" in the container. After waiting for the dry ice to dissapate (sublime) the lid is then firmly attached to seal out unwanted air from entering. The theory is that the CO2 displaces the air in the container leaving only the inert gas (CO2) behind. I would like to say that CO2 is inert under some circumstances, but in a closed container with food it is not. CO2 exposed to moisture, any moisture will react to produce acidic compounds such as carbonic acid. Although this is a weak acid it will have a detrimental effect on long term storage of food. Any food will have moisture of sufficient quantity to react with the CO2 with the possible exception of foods that are freeze dried. The ideal container filler is Nitrogen. It is inert, cheap, and readily available. Although introducing it into a container with stored foods is a bit more difficult, the long term storage benefits are greater than CO2. I use a 12" PVC pipe, 18" high. It has a Plexiglas sheet that measures 16"X16"X1/2" glued with silicone seal to the bottom. The top is a round 12-1/2" X 1/2" Plexiglas plate with a gasket made of a bead of silicone. Attached through hoiles drilled in the side of the PVC pipe, are 3 connections. One is to a Vacuum gauge. One to a tee connection one side of which is connected to a vacuum pump the other to a vent valve opened to the atmosphere. The third connection is to a nitrogen tank. I place a gallon jar with the top slightly loose in the PVC pipe. I place the round lid on hte pipe. I run the vacuum pump down to 28.5" vacuum, at that time I open the Nitrogen source into the pipe. All air had been removed and the nitrogen is replacing the space in the jar left by the evacuated air. I shut the vacuum pump doen and wait until the pressure reads zero psi. I simply lift the pipe's lid, tighten the cap on the jar with a slight twist and Voila! It is nitrogen sealed. I admit this is a bit more difficult than the C02 dry ice method, but the results are better long term storage....