A few weeks ago I made a European-ish buttercream with roughly these ingredients:

4 large whole eggs plus two yolks; ~1.5 cups of white sugar; ~1T vanilla bean paste (I scraped out the rest of my jar); 5 sticks of salted butter (I like salted butter. Haters gonna hate.)

I beat it over a double-boiler until it was foamy, cooking it to at least 140F. Then I transferred it over to the stand-mixer, beat it until it was cool to the touch, added the butter bit by bit, and continued to beat it until soft and fluffy. It was perfect for my affogato cupcakes.

Half an hour ago, I made a lemon-polenta loaf, but I don't like powdered sugar glazes, so I thought I'd beat a bunch of lemon juice and lemon juice powder into some of the left-over vanilla buttercream living in my fridge. I did that, and the texture is weirdly reminiscent of mayonnaise. Not bad, just noticeable.

And when I thought about it, I realised it has all the necessary components. Eggs, oil (in this case just butter), and acid (about a tablespoon each of King Arthur lemon juice powder and fresh lemon juice). The eggs and oil were already emulsified, which seems to be the hardest part of mayonnaise-making, and I just beat the acid into my preexisting emulsion. Except for the vanilla and lots of sugar, it fits the definition (I think).

So my question is, could I, in fact have turned my fancy buttercream into mayonnaise? Or is this just a trick of texture? Is there any way I can tell for sure with a little I save out? If it's not mayonnaise, then why not?

Corollary-type question: If this is mayonnaise, would there be anyway to make a tart European-ish buttercream without it turning into mayonnaise...?

  • A little OT, but wouldn't a "European" buttercream be the traditional creamed butter and sugar?
    – Niall
    Jun 24, 2017 at 11:46
  • 3
    Nope. Butter and powdered sugar creamed together with a little milk is considered American buttercream, as made famous by Wilton decorating. It's the easiest and sweetest. European buttercreams, in general, involve emulsifying pasteurized, partially cooked eggs with butter. I'm doing a sort of French buttercream, since it involves the yolks, but using a sort of Swiss meringue method, although I beat the eggs a lot longer over the hot water than you're supposed to, to make sure they're pasteurized. That's why I called it "European-ish." I still need to try a German buttercream. :P
    – kitukwfyer
    Jun 24, 2017 at 13:24

1 Answer 1


It might have the consistency of mayonnaise but so do many sauces, sweet or savory. If it tastes good to you, it's fine so use it.

What I do when I want a tart citrus taste (for many things, not just icing) is add citric acid crystals. I consider citric acid to be essential in a well-stocked kitchen. If you'd like it to taste like lemon or orange, add some finely grated peel of which ever you prefer. I find a slightly tangy orange flavored icing goes wonderful with chocolate cake.

I can't say how much citric acid to add as I rarely use a recipe. When you're adding butter and whipping the icing, I think that's the best time to add a little citric acid (and peel, if you wish). Start off with just 1/8 teaspoon and after incorporating it well, take a taste. Start adding it well before you've whipped in all the butter. Keep adding 1/8 teaspoonful at each time (or less when you think it's almost right). Keep track of how much you've added so you can write it down for next time. Use a little less if you include orange zest as oranges aren't meant to be as tangy as lemons. Personally, I like tangy taste to many foods.

I use salted butter in all my baking too and simply don't add any extra salt. I like salt. I've asked friends if they found it a little salty and no one said they did.

  • 2
    I use salted butter and still add salt, generously. That's a really smart idea-- I'm lucky since I happened to have lemon juice powder this time. What I've done in the past is actually cook corn starch with whatever fruit juice I'm looking for to make a concentrated, gelled paste that I can break up and beat in. But that affects the texture in its own way too. Still, I'm curious if the emulsification of egg and fat here counts as a mayonnaise, and if the acid chemically changes anything to make it feel mayonnaisey...
    – kitukwfyer
    Jun 24, 2017 at 0:18
  • 1
    No, I don't think anyone would consider an emulsion of eggs, fat or oil and acid being a mayonnaise despite the texture. Hollandaise sauce is an emulsion of butter, egg yolk and lemon juice. Same with Caesar dressing (not the horrid bought stuff). There's no chemical reaction when acid is mixed with fats and egg yolk. The IUPAC (International Union of Pure and Applied Chemistry) defines an emulsion as a fluid system in which liquid droplets are dispersed in a liquid. en.m.wikipedia.org/wiki/Emulsion
    – Jude
    Jun 24, 2017 at 18:12

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.