N.E.T (naturally extracted tobacco) e-juice is a type of e-juice that has been flavored with extracts made from macerated tobacco. Typically the process involves soaking tobacco leaves in PG or VG (or both) for long periods of time. The resulting liquid is then filtered, and the final extract is then used much like any flavoring would be used in any e-juice.
The flavor from N.E.Ts is not like artificially flavored tobaccos e-juices at all. Artificial (or synthetic) flavorings try to mimic a “smoking” flavor (which rarely if ever is accomplished), where N.E.Ts are more about the actual taste of the tobacco itself, unburned. The flavor of these kinds of tobacco juices can sometimes draw an immediate recall to the smell of a fresh pack of cigarettes, pipe tobacco, or cigar.
The flavor that generally comes through in an N.E.T ejuice is a mixture of the earthy tobacco, the tobacco’s casing (a flavoring added to virtually all smoke-able tobacco to make it more palatable), and its top dressing (flavors added to tobacco responsible for aroma and some taste).
While there is no rule against adding flavors to N.E.Ts after the extraction, typically it is left as is, with no adulteration.