Effects of different harvest seasons in some olive varieties onphenolic compounds in olive oil and sustainable oil quality

Olive oil is known not only for its taste and aroma properties, but also for the health benefits of the phenolic compounds it contains. For this reason, the number of studies conducted to examine the quality of phenolic compounds and their effects on health has increased in recent years. The ripening stage and genotype are one of the most important factors that determine the phenolic content and quality of olive oils. This research aims to investigate the effect of three different harvest periods (October, November and December) on the polyphenol composition and peroxide value of olive oils obtained from Arbaquina, Ayvalık, Gemlik and Nizip Yağlık olive cultivars in 2020 and 2021, grown under Şanlıurfa conditions. intended. Various parameters such as total polyphenols, specific phenols and peroxide value were evaluated in olive oil. The results showed that all parameters changed significantly during ripening period, and the best harvest time was found to be October. When evaluated in terms of cultivar, it was determined that the olive oils of Gemlik and Ayvalık varieties,had the highest polyphenol content among the four varieties grown in Şanlıurfa c0nditions. The maturation period does not have a significant effect on the peroxide parameter. It was observed that there were differences between the varieties, but all of these values were below the legal limit of 5 meq O 2 kg −1 (Refined Olive Oil), which is the highest quality value. The results regarding polyphenol composition showed that all olive oil samples were compatible with olive oil polyphenol concentrations in previous studies. The results show that ripening period and genotype have a significant effect on total phenolics and specific phenolic compounds.