Technique #4: Make Great Vinaigrettes

In many ways, vinaigrette is really the ultimate sauce, bringing brightness, acidity, and richness to just about any savory dish, from roasted vegetables to grains to sandwiches to cooked seafood or poultry.

The key to a great vinaigrette is emulsification. An emulsion is simply a cohesive combination of two liquids that don’t ordinarily mix (like oil and water). In a vinaigrette, those two liquids are oil and, typically, vinegar or lemon juice. The only way to mix them properly is to combine them strenuously enough so that the oil breaks down into such tiny droplets that they remain separated and surrounded by the vinegar droplets.

Thus the two liquids become one. Such oil-in-liquid combos are the most common type of kitchen emulsion, but they’re not the only one. Butter and peanut butter are both examples of water-in-oil emulsions: Their fat content is so high that droplets of water are dispersed throughout the fat.

An emulsified vinaigrette works best for keeping your salad greens crisp and unwilted because the vinegar surrounding the droplets of oil prevents the oil from directly contacting the greens. (Plus an emulsified vinaigrette clings more effectively, guaranteeing balanced flavor in every bite.) Whisking a vinaigrette right in the bottom of the salad bowl lets you tailor its flavors to the salad you’re serving.

But we also like to make a larger batch of vinaigrette to have on hand anytime the mood strikes. How do you make that emulsion last? It’s not about the method used for combining, be it shaking, whisking, or using a blender or food processor. Rather, it’s about the emulsifiers and stabilizers used.

Many vinaigrettes contain mustard or mayonnaise because they are effective short-term emulsifiers. We have learned that molasses is the secret weapon for longer-term stabilization. It contains compounds that increase the viscosity of the emulsion so much that it becomes difficult for the oil droplets to coalesce back into larger drops. (Genuine aged balsamic vinegar contains similar compounds.) And fortunately, the amount needed to stabilize an emulsified vinaigrette is not so much that it results in a sweet dressing.