What is the method and ingredients for making small hard meringues using a whipped cream charger? How do I combine the ingredients in the charger prior to whipping? Please help - I can't find this anywhere.
Actually, this can be done but it may not be convenient to do if you aren't in a restaurant setting where this can streamline your process. If you take equal parts egg whites and sugar, beat them together, cook at 74C for 30minutes and then transfer them to the siphon and charge with 4 cartridges, dispense to desired shape, and then bake at 150C until set (this will vary depending on size and shape) you should be good to go.
As I said, this is about the same as doing it the old fashioned way, time wise.
As the comments above have summarized, this probably is not practically possible.
Egg whites form a foam when the proteins are coagulated, trapping the water in a film that holds the air bubbles. This may require extended mechanical emulsification not provided by the pressurized gas.
Aaronut also notes that in regard to the pressurized devices:
Note that I wikid this so I am not farming rep; feel free to edit and clarify.