Quality plays a key role in the marketing of vegetable oils. This quality is influenced by a number of factors, including variety, crop management, date of harvest, place of cultivation and extraction procedure. 

The objective of our study was to determine the ideal seed harvest period to reach their full potential of quality by analyzing the variation of chemical quality and antioxidant activity of Pistacia lentiscus seed oil in three different stages of maturation.

 The results obtained in this study indicate that as maturity progressed, there was a decrease in acidity (7.13-2.61%), chlorophyll content (24.43 - 4.69 ppm), and the total phenol content (808.22 - 191.24 mg GAE / kg). while there was an increase the oil content (11.07- 33.4%) and the composition of monounsaturated fatty acids (44.36- 54.43%), mainly oleic acid (43.11- 52.01%). Oil extracted from first stage (green seeds) showed the highest percentage of DPPH inhibition with around 57.56% followed by red seeds with a DPPH inhibition percentage of 49.99%. Earlier harvest would produce lentisk oils of good quality, stable and a composition rich in natural substances. The optimal stage of harvest is proposed by considering the compromise between the quantity and the quality of the studied parameters.