Egg white: nutrition and how to use it

Fun facts

• Egg white is about 90% water, and nearly all the rest is protein. That is why 100g of egg white has only about 52 kcal, 10.9g of protein and 0.2g of fat.
• The white of one medium egg weighs about 33g and gives you around 3.6g of protein for under 20 kcal.
• All of the vitamin A and almost all of the fat sit in the yolk. Egg white lists 0 for vitamin A, so skipping the yolk means skipping that too.
• When you whisk egg whites, the proteins unfold and trap air bubbles. That is how egg whites become meringue, sponge cake and the fluffy foam on many desserts.

Choosing and storing

You can separate whites from fresh eggs yourself or buy pasteurized liquid egg whites in a carton. Separated whites should go in a sealed container in the fridge and be used within a few days. To keep them longer, freeze them, then thaw in the fridge and use as usual. For cartons, follow the use-by guidance on the pack once opened.

Cooking it well

Egg whites turn rubbery fast over high heat, so fry or steam them over medium heat to keep them tender. When whipping, the bowl and whisk must be spotless, with no oil and not a speck of yolk, because fat makes the foam collapse. Eat your egg whites cooked: raw egg white contains a protein that locks up the vitamin biotin, and cooking switches it off. For a full comparison, read egg whites vs whole eggs.

Frequently asked questions