FOOD FOR THOUGHT: Marvelous Glop

I have always had an inquisitive mind, and as a professional cook I question foods and recipes -- what they are made of, how they are made, when and where they originated, that sort of thing. I am also drawn to simple foods; ones where a few ingredients combined together create something altogether different and good. These are the types of foods that are often readily available to purchase, but when made from scratch you realize how and why they came about -- because they are simple to make and extremely delicious. In most cases these simple homemade foods are far superior to their supermarket cousins. Bread is a good example of this, tomato sauce is another, and homemade mayonnaise is too. Mayonnaise is so commonplace in today's world that it's used without thinking about what it actually is. You may already know that it's high in fat, and that it contains a high proportion of oil and egg, at least the "real" ones do (imitation, low fat, and no fat mayonnaise are a stark contrast and cannot even be considered a comparison). Mayonnaise is a luxury, there's no question, and it is also food science in a bowl. It's an amazing thing, actually, to make mayonnaise from scratch, it's nothing short of alchemy.

Mayonnaise is an emulsion. The definition of an emulsion is the combining of two or more ingredients that do not normally combine. In the case of mayonnaise the lemon (or vinegar) and oil are emulsified into a homogonous mass. There are two types of emulsions: temporary and permanent. An example of a temporary emulsion is vinaigrette sauce; mayonnaise is a permanent emulsion. To create a permanent emulsion an emulsifying agent has to be employed. The emulsifier in mayonnaise is lecithin, which is a naturally occurring protein that is found in eggs, specifically in their yolks.

The concept of an emulsion is simple--whisk and beat together two ingredients that normally do not combine until they break apart into small enough droplets that they seemingly blend together and are indistinguishable from one another. Ultimately the two previously separate ingredients become one. The tricky part is keeping them that way. This is where an emulsifier comes in.

Classically, when mayonnaise is made egg yolks are vigorously beaten with a little acidic liquid (lemon juice or vinegar), salt, and mustard. Beating the yolks aerates them, meaning that it incorporates air into them and will ultimately make a more light and fluffy sauce. Once the eggs are sufficiently aerated, oil is slowly incorporated into the yolks. This is initially done in a very thin stream but once it "catches," the oil may be added at a much faster rate. As the oil is whisked and beaten into the yolks an amazing thing happens: the ingredients in the bowl change color and become a thick mass. What is happening is as the oil is being broken into smaller and smaller droplets--through whisking--and the lecithin is wrapping itself around each droplet, which keeps them separate, and sort of piles them up rather than allowing them to run together. This is the reason that a properly made mayonnaise does not run, that it is thick enough to be spread.

This may sound somewhat technical, but it's just meant to sort of deconstruct what mayonnaise is, to illustrate how it is made. And while making mayonnaise is a simple process, as with any recipe there are a few guidelines to follow. The two most important considerations have been previously mentioned--aerate the yolks sufficiently, and add the oil in a slow but steady stream. Another thought is to keep the liquid, yolks, and oil in proper proportion. One yolk has enough emulsifying power to thicken 1 cup of oil, any more and you risk breaking (separating) the emulsion; there simply would not be enough lecithin to coat all of the oil droplets. And slightly more than 1 tablespoon of lemon or vinegar is enough acidic liquid to offer 1 cup of oil proper flavor and consistency; any more and the mayonnaise may be runny.