Re: Why do the vegetable bags preserve the vegetables shelf life?

Some vegetables and fruit give off ethylene gas.  This gas increases the 
rate of ripening.  These “Green” plastic bags contain a polymer that 
absorbs this gas and or allows it to pass through the bag thus slowing 
the ripening process. You should be careful in re using these bags and 
make sure that they are free of all microorganisms between uses.