The chief purpose of egg whites in baking is to lend structure to your baked goods. Their unique properties help them to leaven such things as cakes without the aid of any yeast or chemical leaveners.
Don?t get confused if a recipe calls for beaten egg whites when it says ?"until foamy", "until batter falls from the beaters in ribbons", "until soft/stiff peaks form".
Some say to use copper bowls - I don't. I feel that the copper ions migrate into the egg whites and they will also take on a yellowish hue and I do not want copper in my food, nor do I want that yellowish tinge.
For that extra stabilization you can add cream of tartar or a pinch of salt when you are beating them, if you want.
Your "frothy" stage is the first stage you will hit - which takes about 30 to 60 seconds to reach. It is at this point that you would add your salt or cream of tartar.
Once your cream of tartar is fully incorporated, you can begin to add your sugar slowly - either in a small steady stream of one tablespoon at a time - your preference.
Once your sugar is fully incorporated, the batter will look thick and creamy. Lift your beaters and the batter is going to ?stream? down off them. You can lift the beaters to check your whites any time. Beat a bit longer and you will have "ribbons".
The difference between the streams and the ribbons - the streams do not rest on the surface of the batter; the ribbons will.
The next thing you will see are ripples on the surface of the eggs as you beat them - and they remain on the surface. You are getting close to the "soft peaks".
Soft peaks and glossy are the very same thing. Soft peaks can be anything from a very soft peak that fall almost immediately to those that stand a little longer.
Stiff peaks are just that. They do not fall at all. At this point you need to be careful that you do not overbeat.
You will know when you overbeat your whites - they have lost their glossiness due to the proteins breaking down. They've lost air.
Remember - soft peak egg whites should stick to the side of the bowl and not look liquidy; the peaks will for and the tips of the peaks will curl over.
But by incorporating beaten egg whites in a cake, pancakes, waffles, etc. you are producing a much lighter finished product - one that is not so dense.
Hope this helps.
