In the kitchen, an emulsion is normally the combination of fat and water (or water-based) ingredients. We first encounter natural emulsions when we drink milk and then use cream. We make emulsions when we create a Hollandaise or mayonnaise sauce or a vinaigrette to dress a salad. The result of emulsifying is twofold, dispersing a strong flavour in a usually blander medium, think of the taste of shallot, tarragon and white wine vinegar in the classic Béarnaise and the resulting mouthfeel, the smooth, glossy experience of eating mayonnaise.
So how do cooks combine fat and water even though they don’t like to mix? By using shearing power, that is shaking, stirring, whisking and blending. The physical action disperses one ingredient throughout the other. Emulsions are unstable by nature, your fresh hollandaise splits and your vinaigrette separates but this can be prevented by using emulsifiers and stabilizers. Egg yolks, mustard, and garlic all act as emulsifiers which chemically bind fat and water molecules together. In commercial food production and molecular gastronomy gums, starches and plant particles all act as emulsifiers.
100 ml Virgin Olive Oil
100 ml Sunflower Oil
2 free-range Egg Yolks*
2 tablespoons good White Wine Vinegar
1 tablespoon freshly squeezed Lemon juice
½ teaspoon fine Salt
½ teaspoon English Mustard powder
A pinch of Caster Sugar
Place a glass bowl on a damp cloth to prevent slipping. Whisk together egg yolk and the dry ingredients. Combine lemon juice and vinegar in a small jug then thoroughly whisk half into the yolk mixture. Whisking briskly add the oil a few drops at a time until the liquid starts to thicken (you have formed an emulsion). Increase the flow of oil to a constant, thin stream. Once half of the oil is in add the rest of the lemon juice mixture. Continue whisking until all of the oil is incorporated. Store in the refrigerator.
If your mayonnaise separates or curdles you can recover the mix by whisking in a tablespoon of boiling water to the mayonnaise which should combine the mixture together. If this does not recombine the mixture start the process again with a further egg yolk in a clean bowl and whisk in the curdled mixture a tablespoon at a time.
*There is a slight risk of salmonella and other food-borne illnesses from using raw unpasteurised egg, use only unbroken fresh eggs and do not consume if pregnant or feed to infants.
3 free-range Egg yolks
200 gr Unsalted Butter
2 teaspoons fresh Lemon juice
2 teaspoons warm Water
A pinch Cayenne Pepper
Place the butter in a small pan and set on the back of your stove or hob. The pan does not need to be heated directly just placed somewhere warm enough to melt the butter. Allow the milk solids to sink to the bottom of the pan and decant off the clarified butter. Set aside and keep warm. Place a medium glass or stainless steel bowl over a pan of gently simmering water, being careful not to let the bowl touch the water. In the bowl whisk the egg yolks until they are pale yellow and the resulting mixture has a thick creamy texture. Switch off the heat.
Using a small ladle pour in a thin stream of the warm butterfat while continuously whisking. Continue until all the liquid is incorporated. If the resulting sauce becomes too thick, thin with a little warm water. Add the lemon juice, season to taste and serve. The Hollandaise will keep warm set above the warm water covered lightly with tin foil for fifteen to twenty minutes.
If your Hollandaise splits or curdles you have probably tried to add the butter too quickly, a couple of teaspoons of freshly boiled water whisked vigorously into the split sauce may help retrieve it. If this does not work, you can whisk up a further egg yolk in a fresh clean bowl then slowly add the split hollandaise whisking all the time.