Egg White

On the surface of it, an egg white isn’t a very interesting thing. It’s colorless with very little flavor and is made up of about 90% water. However there’s quite a lot of magic in that last 10%. How so? Because that’s where the proteins are. The white contains about half the total proteins of the egg, most of which are different from those of the yolk, and which do some pretty interesting biological jobs. Some of them bind up vitamins, others digest cell walls, still others bind to digestive enzymes rendering them useless. All combined they serve to make the white of an egg a very unfriendly place for invading microbes. They’re a big part of the reason an egg can be stored for so long.

When they aren’t busy protecting an embryo, egg white proteins are great for bakers. They’re rather unique in that they can be uncoiled with just a whisk and a little elbow grease. At that point they’re fabulous for creating foams. The reason they’re so good at this is because they have regions along their length that love water (are hydrophilic) and other regions that hate water (are hydrophobic). The end result being that they love the surface of bubbles, as all the sections of the protein can get their needs met. They can stick their water-loving parts in water, their water-hating parts in the air, and they’re happy.

The nice thing is that once all those proteins are arrayed at the surface of the bubble, they begin bonding to each other, if rather weakly. The network they create reinforces the wall of the bubble, preventing it from popping, even if other substances are subsequently introduced (fat, sugar, etc.). The end result is a foam, but not just any foam: one that will continue to maintain its volume after other delicious components have been added. So say hello to meringues, buttercreams and all sorts of other lovely things I couldn’t live without. So thank you, boring old egg white. My kitchen would be a much duller place without you.

16 thoughts on “Egg White”

  1. Can’t say they are my favorite eats without the yolk (as you know I collect yolks at times) but they do have their place in baking (and cooking too). Another great blog. Egg-cellent.

  2. Hi Joe,

    I went into an ice cream making spree this summer and am now left with 2-3 dozens of frozen egg whites in my freezer. Do you have any reco’s for some easy desserts I can make that use up a lot of egg whites besides angel food cake and meringue? I did find your Pavlova recipe and have already added it to the list.

      1. LOL – what ice cream? oh you mean the ones that added themselves to my spare tire? the only reason we made so much was cause we kept eating it all up…that and as a way to use up all those pounds of strawberry and black raspberry we picked. Thanks for the suggestions, looks like I’ll be making more yummies to add to my spare tire! 😀

        1. Well…store bought works too! 😉

          Black raspberry off the bush…I’m jealous!

          – Joe

          1. well if you’re ever in the mood for a road trip in late june/early july, stokes berry farm in wilmington, OH is where we went – not horribly long drive from louisville. the black raspberries are really fun to pick and were delicious. made some awesome black raspberry dark chocolate chip ice cream.

          2. Wow that sounds good. We may just do that. We’ve barely explored Ohio and there’s much there to see!

            Thanks Deb!

            – Joe

  3. Hey Joe,

    I like to make Swiss meringue buttercream but I am paranoid about using raw egg whites, especially if I’m feeding it to other people. My question is… what happens if I heat my egg whites too much when I’m melting it with the sugar? I’ve tried prolonging the mixture over the water bath while constantly mixing and nothing bad really happened but what else could happen aside from making syrupy scrambled egg whites?


    1. Hi Imdy!

      Sorry for the very late reply! I understand the worry about egg whites. Ever consider using pasteurized eggs? They’re not as great for whipping but should work pretty well for a buttercream like this.

      But to answer your question, too much heat will curdle the proteins, making them less whippable. You don’t have to take it all the way to the scramble point for the whites to be effected, so be careful!


      – Joe

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