How Do You Keep Egg Whites From Deflating?

How Do You Keep Egg Whites From Deflating? Cream of tartar (potassium acid tartrate) is a byproduct of wine production (and an essential ingredient in snickerdoodles). Adding the proper amount of cream of tartar will prevent overbeating of egg whites 100% of the time. How do you keep egg whites from collapsing? If clumps are