What can we use to make these foams? Well, one of the most common agents used is something we’ve all likely got in the kitchen: egg white. Egg whites are largely water, but most of the remainder consists of protein. These proteins can act as surfactants, stabilising air bubbles to generate a foam. Some people get worried about the risks of salmonella from raw eggs, but in reality the chances aren’t to dissimilar from that of being struck by lightning. Though there is a small risk, it’s often vastly exaggerated.