Mastic is an aromatic, translucent sap that oozes after "scratching" the bark of the tree in mid-summer. The dripping mastic solidifies in the scorching sun and dries into semi-transparent, white resin with a distinctive aroma. Villagers harvest and clean the solidified resin pieces and then deliver them to the mastic growers' cooperative. The co-op then manages the further processing and packing of mastic for international trade. The mastic is also used for products such as essential oil, powder, and the famous ELMA chewing gum.
Chios mastic resin consists of 70 identified ingredients, many having therapeutic, medicinal, and aromatic properties. Today, we know it consists of 3% essential oil, 25% natural polymer, and 72% total extract. However, the full composition of mastic resin has yet to be fully studied.
Aromatic components of the essential oil for perfumers and for food and beverage flavorings have been studied and found to be mainly composed of α-pinene, mycerene, and β-pinene with earlier studies indicating also limonene and trans-caryophyllene.