Abstract Climate change is increasing heat stress in many olive‐growing regions, raising concerns about its effects on oil quality and cultivar performance. This study investigated the impact of high temperatures on the quality and chemical composition of olive oil from three irrigated Olea europaea L. cultivars, Arbosana, Chemlali, and Koroneiki, grown under arid climate conditions in southern Tunisia (Sfax, Mahres). The research aimed to clarify how heat stress influences key oil quality parameters and whether cultivars exhibit distinct adaptive responses. Over 3 years, fruit weight, oil content, and oil quality were analyzed. Results differed across cultivars. Chemlali showed the highest carotenoid concentrations (14.54 mg kg −1 ) and Koroneiki showed the highest chlorophyll level (5.03 mg kg −1 ). Significant differences in total phenol content were recorded, with Koroneiki reaching 940.14 mg kg −1 , followed by Chemlali (409.41 mg kg −1 ) and Arbosana (320.66 mg kg −1 ). In terms of fatty acids, oleic acid remained dominant in all cultivars (>55%), reaching 74% in Koroneiki. Koroneiki also had the lowest palmitic acid (12.59%) and linoleic acid (8.40%). All cultivars preserved stable oil quality under high temperatures and met extra virgin standards. Notably, heat stress increased oil concentration at harvest, exceeding 21% in all cultivars. These findings showed that high temperatures influenced several oil composition traits, and they do not necessarily reduce overall oil quality.
Ayadi et al. (Thu,) studied this question.