For instance, in a traditional real custard (crème anglaise) or confectioner's custard (french pastry cream) recipe, you will find it comes up frequently: first you are instructed to boil the milk, then to beat the egg yolks and sugar together for a good while until the mixture turns pale. This happens as the beating incorporates air into the mixture in the form of tiny bubbles, which create the paler colour.
Then we pour the hot milk into the mixture and mix well. Result: a liquid (milk+yolks+sugar) and, most noticeably, a lot of froth, which we don’t need, from all the bubbles created earlier.
This froth will drive you up the wall for the whole time you are trying to cook the custard, as it hides the surface and only disappears when the custard starts to thicken. In a word, this froth on the top is a pain!
So, what can we do about it? Well, that’s easy: it's better just to mix the egg yolks and sugar briefly with a whisk or soft spatula, then continue with the recipe. Beating the yolks for longer until pale doesn’t add anything significant to the recipe.
While we’re on the subject, here are answers to a few basic questions:
- Does beating the egg yolks until pale serve any purpose ? No.
- Will it make any difference to the texture in my recipe if the yolks are beaten or not? No (I tested this by making a confectioner’s custard without creaming the yolks: impossible to tell the difference in either taste or texture).
- Will beating the yolks or not make a difference to how the recipe tastes? No, none whatsoever.
- Will beating the yolks until pale make any real difference to my recipe? No, other than making it take longer, for nothing…
In other words, when a recipe tells you to beat the egg yolks until pale, you can quite happily dispense with this step, as it serves no useful purpose, other than wasting your time and creating annoying froth while you cook the custard.
To sum up: Is it necessary to the cream egg yolks when making a custard? The clear answer is no. In fact, it serves no purpose in the vast majority of recipes (I’ve been looking for an exception where it might be useful, but not found one).
PS: Just one slight damper on what I’ve just said, chipped in by my son Nicholas, who is a professional cook (and his dad’s pride and joy!). He tells me that he systematically creams his egg yolks because that’s how he was taught. The froth, which is admittedly annoying, disappears just as the custard is cooked, so this is a pretty good indicator that it’s time to stop the cooking. Now that makes sense…
