I purchased the bags because I'm tired of throwing away food, My first and easiest test was with bananas. I put one in a Green bag, one in a plain clear plastic bag and one bare on the shelf. After a week the one in the clear plastic bag fared a little better than the bare one, but I am IMPRESSED with the green bag results. What a difference. I'm going to use these bags on other things. I am also going to set up a time-lapse camera to really show that the "proof is in the pudding".