Here’s a terrific web site on moths.
Q: My husband and I are having a problem with moths in our pantry. We have asked several different "professionals" at home improvement stores, one with a so-called masters degree in getting rid of bugs, and none of the advice we have received has seemed to work. Our latest attempt was to remove everything from our pantry throw away any and all opened items and bug bomb the pantry TWICE. We were rid of the moths for about an week and all of a sudden they returned. K.L., Frisco.
A: Bombing is the worst thing you could do. Contamination now covers all the surfaces in the rooms that were exposed - and the insects weren't controlled - as you know. Put the grains and flours in the freezer for a day or two when they come home from the grocery store. Then put out glue traps. The ones that work the best are those shaped like little tents.