Scents of Earth Maydi Frankincense Resin
Skip the synthetic gum base entirely. The cleanest chewable is a single tree resin, Chios mastic or clearly food-grade frankincense, with no sweetener, no flavor and no coating. Avoid flavored mastic gums, pressed tablets and “natural” gums padded with xylitol or an undisclosed base.
A US source in the Forbidden Fruit directory. Check that it ships to Europe; where it does not, the directory lists a European alternative alongside it.