Olive Oil in Baking: Swaps and Ratios
Olive oil belongs in baking more than most home cooks realise — it makes some of the moistest, longest-keeping cakes there are. But it isn’t a one-to-one swap for every fat, and it suits some bakes far better than others. Here are the working rules.
The reason a good olive-oil cake stays tender for days while a butter sponge dries out by day two comes down to physics: liquid fat coats the flour proteins and holds moisture in the crumb better than solid fat does. That is the case for baking with olive oil, and it is a strong one. The catch is that fat behaves differently in a batter depending on whether it is solid or liquid, and how much water it carries — which is exactly why you cannot simply pour olive oil in wherever butter is called for and hope.
Swapping for butter and other oils
Replacing a neutral oil with olive oil is the easy case: use the same amount, one for one, and accept the flavour it brings. Swapping for butter is where ratios matter, because butter is only about 80 percent fat — the rest is water and milk solids. A reliable guide is to use roughly three-quarters as much olive oil as the butter called for (about 3 tablespoons of oil for every 4 of butter), since you are replacing solid fat-plus-water with pure liquid fat. You also lose butter’s creaming ability, so olive oil suits recipes that don’t depend on whipping air into solid fat.
| Replacing | Use | Notes |
|---|---|---|
| Neutral oil (sunflower, canola) | Same amount, 1:1 | Straight swap; you gain olive flavour |
| Butter (melted-style bakes) | ~3/4 as much (3 tbsp oil : 4 tbsp butter) | Butter is ~80% fat; oil is pure fat |
| Butter (creamed cakes, buttercream) | Don’t swap | You lose the creamed-air structure |
| Shortening / lard | ~3/4, case by case | Texture changes; test a small batch |
Where it shines, where it doesn’t
Olive oil is superb in moist, robust bakes: citrus and almond cakes, chocolate cakes, focaccia and other breads, where its fruitiness is an asset and its liquid fat keeps the crumb tender for days. Use a milder, riper oil when you want it in the background, or a greener, peppery one when you want it to be part of the flavour — in a savoury bread or a rustic olive-oil cake. Where it struggles is in bakes built on creamed butter and on butter’s flavour: laminated pastry, shortbread, buttercream. There, olive oil isn’t a swap — it is a different cake.
The two-oil rule for bakers
Here is the part the conversion charts leave out: which olive oil. For most cakes, a milder, ripe oil disappears into the crumb and just leaves it moist — you do not want your fiercest, peppery bottle fighting the sugar and chocolate. Save the green, bitter finishing oil for bakes where you actually want to taste the olive: a savoury loaf, a rustic citrus cake, a focaccia. Matching the oil to the bake matters as much as the ratio. A supermarket everyday oil bakes a lovely cake; your special bottle is wasted, its aromatics baked off in the oven.
- 1:1 when replacing a neutral oil; 3:4 when replacing butter.
- Olive oil suits oil-method cakes, quick breads and muffins.
- It won’t replace creamed butter in shortbread, laminated pastry or buttercream.
- Use a mild ripe oil to stay in the background, a green oil to be tasted.
- Save your best bottle for the table — heat bakes off its aromatics.
Olive oil in baking: common questions
How much olive oil replaces butter in baking?
Roughly three-quarters as much — about 3 tablespoons of oil for every 4 tablespoons of butter — because butter is only about 80% fat and the rest is water.
Can I swap olive oil for vegetable oil one-to-one?
Yes. Replacing a neutral oil with olive oil is a straight 1:1 swap; you simply gain the olive flavour it carries.
Which bakes work best with olive oil?
Moist, robust ones: citrus and almond cakes, chocolate cakes, focaccia and breads. It keeps the crumb tender for days.
When should I not use olive oil?
In bakes built on creamed butter and butter’s flavour — shortbread, laminated pastry, buttercream. There it is a different result, not a swap.
Should I use my best extra virgin for cakes?
Usually no. A milder everyday oil disappears into the crumb; the fine aromatics of a special bottle are largely baked off. Save it for the table.
For most cakes, a milder ripe oil disappears into the crumb and just leaves it moist; save your green, peppery finishing oil for bakes where you actually want to taste the olive, like a savoury loaf or a rustic citrus cake. And remember the rough rule when swapping for butter: about three parts oil to four parts butter, by volume.
olives101 kitchen practice; the 3:4 ratio follows from butter being roughly 80% fat, the rest water and milk solids.