So, I’m wondering if I have a correct understanding of pipe tobacco: aromatic tobacco can lose its flavor over time if it isn’t stored properly. If it dries out, it often can’t be salvaged. Tobacco that has no flavoring (virginias, latakias, and the rest?) added can be rehydrated and shouldn’t lose flavor over time? It can be aged and also salvaged. What about a blend like Royal Yacht? Are there exceptions?
Almost all commercially released pipe tobacco blends have flavorings added, whether as a casing early on or as a topping later on. Conventional wisdom, (whatever THAT is) holds that flavorings such as are used with aromatics will fade over a number of years. I just opened up a jar of a vanilla flavored aromatic I jarred up a decade ago and it's pungent as ever. So, it ain't necessarily so.
As a rule, Latakia does fade over time, but not always, and not a quickly as some believe that it does. What's fading is not the inherent flavor of the oriental leaf used, but the processing done on it. Some of that smokiness may fade, but then the flavor of the underlying leaf will come through.
Dried out blends can often be revived as long as they haven't gone stale. That doesn't mean that they're going to come back 100%, but 80% is considered a pretty good result, as long as the result tastes good. This varies from blend to blend. I've revived GL Pease Renaissance quite successfully, but GL Pease Haddo's Delight is resurrection proof. It gets, and stays, downright nasty.
The term "aromatic" nowadays refers to strongly flavored tobacco blends like vanilla, or cherry, mango, coconut, or apricot flavored blends. It used to largely refer to what are now called English/Oriental/Balkan blends because their component leaves were highly aromatic.
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