Last year while visiting in Indiana we bought a bottle each of Hard Cider and Dry Sherry. I know that these have more alcohol than a wine but less than something like rum. What I am not sure of is how long can they be kept after opening if we don't use the whole bottle at one time. I've seen recipes that I could use either in but unless I have a crowd and serve the rest of the bottle with the meal I worry that either of them could trun before we finished consuming the rest of the bottle. Does anyone know the "shelf life" of these two?