Effect of temperature and storage period of olive (Olea europaea cv. Zard) fruit on olive oil quality

Black-ripe olive (Olea europaea cv. Zard) fruits, harvested from trees grown in Tarom (Zanjan) climatic conditions, were stored in 92 +/- 2% humidity and three different temperatures (5 degrees C, 8 degrees C and 20 degrees C) for six different periods of 5, 10, 15, 20, 25 and 30 days. Evaluations were made on parameters such as flesh firmness, weight loss, chilling injury and fungus development during storage and relative oil quality. Oils were extracted immediately after fruit harvest and at the end of six predetermined temporal storage periods. Acidity, peroxide value and total polyphenol content were analyzed in each single treatment together with sensorial quality determined for 30 days. The results confirmed that olives stored at 5 degrees C even for 30 days maintained initial sensorial, visual and chemical qualities and at 8 degrees C the quality was maintained for 25 days while olives stored at room temperature led to deterioration only after 5 days of storage.