I have a bunch of egg white protein powder to take as a supplement. Only when I mix it in a shaker bottle, it foams up. Reading the answers about souffles I got the idea that if the egg yolk prevents foaming, and that yolks contain lecithin--that must be what the soy lecithin is for in the commercial egg proteins which don't foam up at all. But that didn't work. What is a powder--natural if possible--that I can add so that it mixes like the store bought stuff?
You're looking for a "food grade" antifoam agent. A brief look at the linked search results shows antifoam powders look to be mostly silicone based. They may or may not work for your heavy protein foam.