When olive oil is exposed to oxygen, light, and heat, it is subject to oxidation and may become rancid. Proper storage can prevent this. As soon as you open the bottle, the oxidation process accelerates, and the oil will degrade fairly rapidly. Make sure you keep your oil in a closed bottle, in a dark container or pantry, away from sources of heat like your stove. Refrigeration will not hurt the oil, however if refrigerated you may notice that the oil will begin to thicken and gel. We recommend you consume our olive oils within 12 months of purchase.