How to Make Mayonnaise by Hand

Mayonnaise is an emulsion. Emulsions are created when two substances (often fat and liquid) are forced together in such a way that it produces a smooth, slightly thickened mixture, where naturally they would separate. Other commonly used examples of stable emulsions are hollandaise and beurre blanc.

Mayonnaise is a stable emulsion. It will not separate once it has formed. A vinaigrette, on the other hand, is an unstable emulsion and its component parts will separate over time.

The basic ratio is 1 yolk: 150ml mild/flavourless oil.

If making mayonnaise in the machine, be sure to make a quantity large enough to ensure the blades make sufficient contact with the ingredients for emulsification to happen.

Vigorous whisking and the very gradual incorporation of ingredients are key to producing an emulsion.

When making mayonnaise the emulsion is created by mixing fat (the oil you’re using) with the water present in egg yolk. When adequately emulsified, the fat is held in suspension within the liquid, creating a smooth homogenous emulsion.

Whether made by hand or by machine, the addition of oil to the yolk needs to be very slow to begin with. Add the oil too quickly and it will split/curdle.

On our Essential Cooking course [see recipe below] we show you how to make mayonnaise by hand, first using a fork to drip in the oil gradually (we use this method for the first third of the oil), then adding just a quarter teaspoon at a time, progressing to a half teaspoon at a time. Only once half to two thirds of the oil has been added, do we add the rest in a slow thin stream.

When mayonnaise splits, it is most likely because the oil has been added too quickly.

You can remedy a slightly split mixture (one that looks greasy) with a splash of lemon juice, warm water or vinegar and vigorous whisking. If badly curdled (completely separated) you need to start with a new egg yolk (and a pinch of mustard powder - the lecithin in mustard powder is a natural emulsifier) and gradually whisk in the curdled mixture and the rest of your oil.

When all the oil is incorporated, you have your mayonnaise, a ‘mother’ or ‘primary’ sauce. Other flavourings can be added to alter its profile, transforming it into a ‘daughter’ or ‘secondary’ sauce. For example, add garlic and you have a new sauce: aioli.

Taste your mayonnaise, and season with salt and white pepper, adding lemon juice or white wine vinegar as needed to balance the oil and acidity.

A well-made mayonnaise will hold it shape on a spoon.

Method

1. Put the yolk into a small, fairly deep bowl and add a pinch of salt and mustard powder. Using a sauce whisk, mix the egg yolk and seasoning together. Place the bowl on top of the damp kitchen paper or cloth.
2. Dip the sauce whisk into the oil and then drip the oil onto the egg yolk. Vigorously whisk the oil into the egg yolk. Continue to add a third of the oil using this drip method.
3. Once a third of the oil has been added and the emulsion created, start adding the oil in a slow and steady stream. If the mayonnaise becomes very thick and looks greasy, add ¼–½ tsp of warm water or lemon juice, depending on whether you think the mayonnaise needs acidity or not. This will make it less greasy, thin it and help it to absorb more oil. Watch to the end of the clip for how to salvage a split mayo!
4. As the mayonnaise thickens and more oil is incorporated, the stream of oil can be increased. Try to incorporate all of the oil to balance the flavour.
5. Taste the mayonnaise. Season it with salt and white pepper and add lemon juice or wine vinegar as needed to balance the oil and acidity.
6. The mayonnaise should be smooth, shiny, and thick. If it is not to be used immediately, cover and refrigerate.