Rubber like skin on surface of chocolate mousse

Question

When I make chocolate mousse, I usually end up with a slightly rubbery surface on the mousse.

To make the mousse, I do the following:

• Melt dark chocolate in a bowl over simmering water
• Separate 2 or 3 egg whites from the yolks
• Whip the egg whites
• Mix the yolks in with the chocolate and add a bit of sugar
• Fold the egg whites in with the chocolate mix
• Transfer to bowls and put in the fridge

Usually when I go to eat them the next day, there is a rubber like surface on the mousse, but underneath it's nice and soft.

I am just wondering what causes this, and how to prevent it?

Asked by GRA

Answer

The cause is that the mousse dries out on the surface. It builds a skin of dehydrated mousse. It happens with most cremes, not only your yolk foam.

To prevent it, put plastic wrap on the mousse. Don't span it over the bowl, press it on the surface itself, without leaving air between the mousse and wrap. Your mousse will stay soft. This also works for custards and starch-thickened puddings.

In general, also cover other things you put in the fridge, or they can get an unpleasant odour.

Answered by rumtscho

Check more discussion of this question.