For most cooks, learning to beat or whip egg whites—into "soft peaks" or otherwise—is a rite of passage. It seems simple: Just whip away until they get light and fluffy, right? Not quite. In fact, the right bowl, beater, eggs and temperature can all affect the volume and texture of your egg white foam. With a little kitchen science, however, anyone can beat egg whites into white, fluffy, dream-like clouds every time.
The Right Bowl
• Use a small deep bowl with a rounded bottom for 4 to 5 egg whites, or a large, deep bowl for more.
• A copper bowl is ideal since it will react chemically with egg whites to form fluffy, high peaks.
• When using a stainless steel or glass bowl, add cream of tartar or lemon juice to achieve the same result as with a copper bowl.
• Avoid aluminum bowls, which can cause whites to turn gray, and wooden bowls, which tend to absorb oils from other usages and can retard the whipping. Plastic bowls can also have a thin, oily residue that may inhibit the whipping process.
• The bowl and beater should be completely clean and dry.
The Right Eggs
• Fresh eggs will achieve the fullest volume as they are slightly acidic and this helps stabilize the proteins. As eggs age, they slowly become more alkaline, which make the proteins less stable.
• The addition of an acid will fluff up your whipped egg whites.
It stabilizes the whites and adds volume. Add 1/8 teaspoon of an acidic ingredient (such as lemon juice, vinegar or cream of tartar) per egg white, except for meringues, where 1/8 is used for 2 egg whites. The acid should be added to the whites just as they begin to become frothy during the beating process.
• You will get more volume when beating egg whites if you first bring them to room temperature. Set the eggs out on your counter at least 30 minutes in advance of your preparation. For a quick method, place the eggs in a bowl of very warm, but not hot, water for 5 to 10 minutes.
• If your recipe calls for the eggs to be separated, do this when the eggs are cold. Then, place the bowl of egg whites in a pan of warm water. Make sure there is no yolk in the whites--if there is any yolk present the whites will not whip up.
The Beating Process
It is best to begin at a slow speed and gradually move up to high when beating egg whites. They will go through the following stages.
• Foamy: The egg whites are still primarily liquid, with some bubbles that may cause the egg whites to look slightly opaque.
• Soft Peaks: The egg whites are now opaque white, will hold their shape in the bowl, and will not slide out if the bowl is tipped sideways. When the beaters or whisk is lifted out of the egg whites, they will form soft peaks that slump over to the side.
• Firm Peaks: When the beaters or whisk is lifted out of the egg whites, the peak will stand erect and not bend over.
• When your egg whites get fluffy...STOP!
If you overbeat them, they will liquify again. Once eggs are overbeaten, they cannot be salvaged.
• Use beaten egg whites right away. Do not let them sit.
Adding to Egg Whites
Other ingredients are often added to beaten egg whites either to help the stability and increase volume or to add flavor.
• To add stability, use a pinch of salt or cream of tartar and add to egg whites prior to beating. This will help stabilize the protein matrix and increase the volume.
• Sugar is often added to egg whites when making meringues and other desserts. The sugar needs to be added gradually to prevent the foam from collapsing--egg whites beaten with sugar added at the same time will not create firm peaks. Unlike plain beaten egg whites, the sugar will cause the egg whites to take on a glossy appearance.
Using Whipped Egg Whites
Whipped egg whites should be used immediately as they may lose volume or weep moisture as they sit.
Never beat or aggressively stir egg whites into other ingredients. Rather, other ingredients should be gently folded into the egg whites. Fold as few times as possible to combine the ingredients and maintain as much volume as possible.