Gees – I wrote a nice long reply and lost it! So, here’s another try at it!
I’ve lost many bags of flour to pantry moths. So, get a Fresh Saver sealer ($16 at Walmart), Get the jar attachment ($28, but remember about regular vs wide mouth issues), get the half gallon size jars (I get them at Ace Hardware).
I have a bread recipe that calls for 6.5 cups of flour. That basically fills up a 1/2 gallon jar. Then I seal it and it’s ready to be used for bread or something else, since I did not add the other dry ingredients.
But, more important – the moths can’t get in! The paper bag is gone, out of the house, gone. It only takes one cleaning of the pantry of those darn moths to realize that you have to check every bag and box for webs, etc.