Olive Oil Salad Dressing: The Ratio and the Order
A vinaigrette is oil, acid, salt, and a decision. Most bottled dressing exists because people were taught the wrong ratio and gave up.
The ratio, and why yours might be wrong
The standard vinaigrette ratio is three parts oil to one part acid. It appears in nearly every cookbook and it is a reasonable place to start.
It is also frequently too oily, and the reason is that not all acids are equally acidic. A sharp red wine vinegar at seven percent acidity behaves very differently from lemon juice, which varies, or from a sweet aged balsamic that is barely acidic at all. Three-to-one with a mild acid gives you a greasy dressing that coats leaves without tasting like anything.
Start at three-to-one, then taste it on an actual piece of lettuce — not off a spoon. Oil tastes different on a leaf than it does alone. If it tastes flat, add acid a teaspoon at a time. If it makes you wince, add oil.
| Acid | Starting ratio | Best with |
|---|---|---|
| Red wine vinegar | 3:1 | Greek salad, sturdy greens, tomatoes |
| Lemon juice | 2.5:1 | Delicate greens, seafood, grain bowls |
| Sherry vinegar | 3:1 | Bitter greens, roasted vegetables |
| Balsamic (aged) | 4:1 | Arugula, strawberries, parmesan |
| Apple cider vinegar | 3:1 | Slaws, apples, anything with pork |
The order of operations
This is the part that determines whether your dressing holds together, and almost everyone does it backwards.
Dissolve the salt in the acid first. Salt dissolves in vinegar and lemon juice. It does not dissolve in oil. If you add salt at the end you get gritty dressing with uneven seasoning, and the flavor never fully integrates.
So: acid in the bowl, salt in the acid, whisk until it disappears. Then mustard and any aromatics. Then the oil, in a slow stream while whisking.
Dijon mustard is not just a flavor here. It is an emulsifier — its compounds hold oil and water together so the dressing stays combined instead of separating within minutes. A half teaspoon per quarter cup of dressing is enough to change how it behaves. A small spoonful of honey or a little minced shallot left to sit in the vinegar for ten minutes does similar work.
Which olive oil
This is the application where a good extra virgin oil is most worth using and most obviously detectable, for the same reason as bread dipping oil: nothing is cooked, so nothing is hidden.
Extra virgin means the oil was produced mechanically, without heat or chemical refining, and passed both a chemical threshold and a sensory panel. The USDA sets free fatty acid content at no more than 0.8 grams per 100 grams for extra virgin, and requires a median of zero defects with detectable fruitiness.[1] The chemistry is only half of it — a technically compliant oil that tastes musty is not extra virgin.
A peppery, bitter oil that seems too assertive on its own is often exactly right in a vinaigrette, because the acid and the salt round it off. Conversely, a mild oil that tastes pleasant alone can vanish entirely once vinegar is involved.
Our Glory Bound Extra Virgin Olive Oil is what we use in the dressings we make in our restaurants, including the feta dressing that goes on our Greek salads. It is pressed in California by a family-run grower and miller we have bought from for years. The whole range is in the olive oil collection, and if you want to try the infused oils in dressings the bundles are the cheaper way in.
Four dressings worth knowing
Greek. Red wine vinegar, salt, dried oregano, a small grated garlic clove, olive oil. That is the entire recipe and it is the dressing that goes on a proper Greek salad — tomatoes, cucumber, onion, olives, feta, no lettuce at all. Let the oregano sit in the vinegar for a few minutes before adding oil; dried herbs need moisture to wake up.
Lemon herb. Lemon juice, salt, Dijon, olive oil, and a large handful of chopped soft herbs — parsley, dill, mint, or all three. Good on grain bowls, roasted vegetables, and grilled fish. This is where a fresh, grassy oil shines.
Rosemary garlic. Sherry vinegar, salt, Dijon, and our Rosemary Garlic Olive Oil in place of plain oil. Because the oil is co-milled, the rosemary is worked into the oil rather than steeped on top of it, so you get an even herbal note instead of a sharp one that fades. Particularly good over bitter greens or warm potatoes.
Creamy feta. Crumbled feta, lemon juice, a spoonful of yogurt, black pepper, and olive oil, blended until smooth. Feta brings enough salt that you should taste before adding more. This is the closest home version of what we make in our kitchens.
Dress at the right moment
Dress delicate greens immediately before serving. Salt draws water out of leaves, and a dressed salad left sitting for twenty minutes is a wilted salad.
The opposite is true for sturdy ingredients. Chickpeas, grains, roasted vegetables, cucumbers, and tomatoes all benefit from twenty to thirty minutes in the dressing, because they absorb rather than collapse. If you are making a chickpea salad, dress it early — we make that point in our chickpea recipes as well.
Use less than you think. Most home salads are overdressed. The leaves should be lightly coated and glossy, with nothing pooling at the bottom of the bowl. Dress in stages, tossing between additions.
Storing
A basic vinaigrette keeps in the refrigerator for about two weeks. Ones containing fresh garlic, fresh herbs, or dairy should be used within three or four days.
Olive oil solidifies when cold, which is normal and not a defect. Take the jar out twenty minutes before you need it, or run it under warm water and shake. If it separates, shake it — that is what separation means, not that it has gone bad.
Store the oil itself away from heat and light. Rancidity is the most common olive oil defect and it is caused mostly by exposure.[2] The cupboard next to the stove is the worst place in the kitchen, and it is where most people keep their oil.
One reason to use more of it
Beyond flavor, there is a reasonable case for eating olive oil regularly. Olive oil is roughly 70 to 80 percent oleic acid and carries phenolic compounds in the range of 50 to 800 milligrams per kilogram.[3] In the PREDIMED trial, a Mediterranean diet supplemented with extra virgin olive oil was associated with a stroke hazard ratio of 0.60 compared with a control diet.[3]
Salad dressing is one of the easiest ways to eat olive oil in meaningful quantity without thinking about it. That is a better argument for making your own than any flavor claim.
What we do
Every dressing in our kitchens is made in house, and they all start from the same California olive oil we bottle and sell. If you would rather have us make the salad, come see us in Hattiesburg, Tuscaloosa, or Ocean Springs.
References
[1] "Olive Oil and Olive-Pomace Oil Grades and Standards." USDA Agricultural Marketing Service.