We’ve already explored temporary emulsions with a basic vinaigrette salad dressing as an example. Now let’s look at permanent emulsions. Once you get the hang of permanent emulsions you’ll be able to produce homemade mayonnaise; creamy salad dressings including blue cheese, ranch, thousand island and caesar; aiolis; and sauces such as hollandaise and béarnaise. But it’s worth a warning I think. The first time you make a homemade chipotle mayo for your sandwich or a béarnaise from scratch for your steak or eggs benedict, you’ll never be the same. You’ll be spoiled by the secrets of a chef!
The science: Stabilizers can keep temporary emulsions suspended longer, but a true emulsifier is needed to make a permanent emulsion. Egg yolks contain a powerful emulsifier called lecithin. Lecithin is a long chain molecule that has one area that likes water (in the vinegar) and another area with an affinity for oil. Enough lecithin molecules surround an oil droplet- bringing their water with them- that the oil drop becomes essentially coated by water. This prevents the oil drop from recombining with other oil drops, and the emulsion is now permanent.
The example: To understand the creation of a permanent emulsion, begin with the following method for making mayonnaise. I’m not generally a big fan of mayonnaise, but this takes less than twenty minutes. And once you have mayonnaise, it can be used as a base for almost all creamy salad dressings and aiolis. The process for making hollandaise and béarnaise is similar but also involves the addition of heat. We can cover that in another post.
Ingredients for Mayonnaise:
- 2 egg yolks
- 1 tsp plus 2 tsp white wine vinegar
- pinch salt
- pinch of cayenne or splash of tabasco
- 8-12 oz salad oil (or any vegetable oil, olive oil, etc) Note: up to 6 oz of oil can be added per egg yolk- more than this and the emulsion can break
- 1 lemon
- In a large bowl, beat the egg yolks, 1 tsp of vinegar, salt and cayenne or tabasco with a wire whip until the eggs become pale yellow. It may be helpful to sit the bowl on a towel or nonskid mat while beating.
- Begin to add oil, drop by drop at first, whisking constantly. The mixture will become slightly thicker as your emulsion begins to form. Patience is key here. If the oil is added too quickly, especially in the beginning, the emulsion will break.
- Once your emulsion has begun, oil can then be added in a thin stream, still beating constantly. The remaining 2 tsp of vinegar can be added, alternating with the oil.
- Continue to add oil and beat until the mayonnaise is thick enough to hold its shape. Adjust with more seasonings if needed, and beat in a squeeze of lemon juice for a brighter flavor.
Mayonnaise can be stored covered and refrigerated for about a week. Technically, pastured eggs are preferred as there is no heating process. You now have perfectly good homemade mayo to use as you would any store bought mayo product. You also have a blank slate for adding any other flavorings to transform your mayonnaise into creamy salad dressings! If there’s interest I can provide ingredient additions for common creamy dressings starting from this mayonnaise base.
Working with emulsions can be tricky. Emulsions can ‘break’ or become unmixed liquids again for many reasons. Adding oil too quickly, not beating constantly, or adding too much oil are probably the most common culprits causing broken emulsions. I broke my first mayonnaise and my first hollandaise in class, but the third time was a charm. Don’t get discouraged… and enjoy your yummy emulsions!