This is merely to set the atmosphere and illuminate the mother character's coping mechanism, but it's a region that fascinates me regardless.
I searched for "West Virginia jams jellies", "West Virginia fruit preserve"/s, replaced "Appalachia" and "Appalachian" for WV, and poked around Chowhound.com and read the Wikipedia article on Southern Cuisine with its actually relatively helpful paragraph on Appalachian cuisine.
I also am re-reading Homer Hickam's memoir "Rocket Boys" (made into the film "October Sky") which has great details about West Virginia coal country and growing up there, but his mother is not the same type as the one I'm writing about, plus he lives in an organized company town, not some cove high up in the mountains, where my character comes from.
EDIT: I totally neglected to mention the time setting: late 1940s. However, any information is welcome. Some of my searches turned up mail-order gourmet outfits, but they seemed to be marketing products popular for national tastes, so I wasn't sure about them.