Magazine · Storage
Oil shelf life: how long it keeps and how to store it
Oil does go off. We explain how long different oils last, how to store them and how to tell when an oil has turned.
How to store
What ages oil
Air, light and heat
Oil turns rancid through oxidation , oxygen, light and warmth attack the fatty acids. The more polyunsaturated an oil is, the faster it ages. Flaxseed oil is very sensitive; saturated oils like coconut are far more stable.
Storage is therefore the biggest lever for shelf life.
Storage and shelf life
- Cool, dark, sealed: a cupboard away from the stove, in a dark bottle, tightly closed.
- Sensitive oils in the fridge: flaxseed, hemp, walnut , and use them up within weeks.
- Stable oils last longer: olive, coconut and refined oils keep many months when stored well.
- Mind the date: the best-before date assumes proper storage and a sealed bottle.
How to tell it has turned
A rancid oil smells and tastes scratchy, bitter and old, a bit like old nuts or paint. Then it belongs in the bin, not on your food. We make no health promises, but rancid fat simply tastes bad and is best avoided. When in doubt, smell and taste a drop. We give you the facts, the decision stays with you.
Sources and further reading
- Rancidification , Wikipedia