cart Shopping Cart cart(0)


Email me when new posts are made to this blog

Science and Cooking: Mayonnaise!

Written by Jacqui on April 5th, 2018.      0 comments

One of the most memorable lab session during my university years was in chemistry, when we made mayonnaise. It was part of a module on colloidal suspensions, since mayonnaise is an emulsion. The experiment was so much fun, but I lamented the fact that we couldn't take it home and eat it because it was not made in a food-safe environment! So today, I'm repeating it in my kitchen!
A bottle of oil, blue bowl, bottle of rice vinegar, 2 brown eggs, black electric whisk on green and blue Fizzics Education tablecloth
What you will need
  • 2 egg
  • 1 cup of oil
  • 1 tablespoon of vinegar/lemon juice
  • Electric whisk or beater, or food processor if you have one
  • Small bowl

  1. Separate eggs to get the egg yolks, place in the bowl.

    2 egg yolks in a blue bowl next to broken egg shell on green tablecloth
  2. Start mixing with the electric whisk, adding oil one teaspoon at a time. Whisk for a good 15 seconds before each addition!

    Whisk in the egg yolks in a blue bowl as oil pours in, all on green tablecloth
  3. Once the desired consistency has been reached, stir in vinegar. This an important step, because the acidity will help the mayonnaise keep for longer by preventing bacteria from growing too much in the raw egg.

    bottle of rice vinegar next to blue bowl of yellow mayonnaise with red spatula sticking out of it all on green tablecloth
  4. Add seasoning (Salt, pepper, garlic, wholegrain mustard) if you wish!

    Silver spoon full of mayonnaise poised over a white ramekin of mayonnaise homemade on Fizzics green tablecloth
What is an emulsion anyway?

It is when two liquids that are normally immiscible or don't mix, come together where one is dispersed within the other in tiny little bits. This can happen through a lot of vigorous and rapid mixing. The main components in mayonnaise that makes up this emulsion is oil and water (in the form of vinegar). If you've done our Layered Liquids or Lava Lamp experiments from the Free Experiments section, you will know that water and oil don't mix. Just like if we were making a salad dressing with oil and vinegar and it goes cloudy when shaken up, but will eventually settle out into two layers. So how do the components of mayonnaise manage to stay together?

Enter lecithin, an emulsifier present in egg yolks. It is an amphiphilic compound, which means it is hydrophilic and hydrophobic at the same time! Parts of the lecithin molecule are structurally very similar to fats with long carbon chains (highlighted in blue and green in the picture below), but it also contains charged groups (in red) on the other end that is water-loving. This combination of features allows lecithin to bridge the oil droplets and the water it is dispersed in, preventing the oil from gathering into a big clump and keep the emulsion stabilised.

lecithin molecular structure

Chemical structure of lecithin

You may notice that your homemade emulsion separates if you add too much oil too quickly, or if each addition was not whisked in enough. Why not use this as an opportunity for some fair-testing and more:
  • How much is too much? Record how much oil you can mix in before the emulsion collapses and separates out!
  • Does the order matter? Try changing the order in which you do each step and see if it makes a difference. Why might that be?
  • What would happen if you used the whole egg? Try it and see!

  • Emulsions are delicate systems; what can destroy it? Check out the milk rainbow experiment for more information on this one!
More science education posts

>100 free science experiments on this website here
Science and cooking Baked Alaska
Science and cooking:
Baked Alaska!
keyboard white buttons green button blog
10 most popular teaching
ideas from 2017!

Happy teaching,


Jacqui from Fizzics
Find out more about the author

NEW Primary science teaching book

Be Amazing; How to teach science, the way primary kids love

Be Amazing; How to teach science, the way primary kids love!

Read more; orange arrow
Want more ideas for teaching science?

Subscribe to the FizzicsEd Podcast!

Listen to FizzicsEd on Apple Podcasts

FizzicsEd podcast available on Stitcher

Join our newsletter for more science teaching thoughts & ideas

Join the Fizzics Newsletter

Got any comments or want to share your own science teaching experiences? We'd love to hear from you below!

Teaching Topics: edchat, food, kitchen chemistry , teaching


Be Amazing Book Front Cover; Ben Newsome, teacher & founder of Fizzics Education. Be Amazing -how to teach science the way primary kids love
Be Amazing!
How to teach science, the way primary kids love

Read more about Be Amazing

Want more science? Subscribe to the FizzicsEd podcast!

Listen to FizzicsEd on Apple Podcasts logo

FizzicsEd podcast available on Stitcher

Australian Small Business Champion for Educational Servicestop 100 coolest company CILC Pinnacle AwardAustralian Science Teachers Association PwC 21CM-Initiative

Love Science?

Signup to our fortnightly email! Learn more

Contact us

1300 856 828

Unit 10/55 Fourth Ave
Blacktown, NSW 2148, Australia
facebook-icon Apple Podcast Icon  twitter-icon
linkedin-icon youtube-icon   pinterest-icon