How mayonnaise is made
A jar of mayonnaise is mostly oil, held in tiny droplets by the lecithin in a little egg yolk.
- stations
- 6
- things upstream
- 38
- raw sources
- 19
- steps from the ground
- 8
The short version
Mayonnaise lives or dies on droplet size. Factories start from a water phase with egg yolk, then inject oil into a high-intensity mixer, often a rotor-stator mixer or a colloid mill, which tears it into tiny droplets that the yolk coats. Smaller droplets make it thicker, whiter and milder tasting. Too much shear thins the batch or breaks it.
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Disperse yolk in water
Egg yolk goes into water in the mixing vessel. It works as both emulsifier and texturizer, so more yolk gives a thicker product with smaller droplets.
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Add seasonings
Salt, sugar, mustard and vinegar join the water phase. The blend can run in batches or continuously, depending on how the plant combines its mixers and tanks.
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Inject cooled oil
Oil is metered into the vessel under strong agitation. Starting with cooled oil gives a firmer texture, and good flow in the vessel lets it go in faster without hurting quality or stretching the mixing time.
Goes in -
Shear the droplets small
A high-speed rotor-stator mixer or colloid mill pours its energy into a tiny volume of product, ripping oil droplets apart. Smaller droplets scatter light differently too, which is why fine mayonnaise looks whiter.
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Mill at the discharge
An inline mill at the outlet of the batch tank gives the emulsion its final shear. Too little or too much leaves it thin, and too much can split it, so operators adjust the mill gap or speed with care.
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Check, fill and seal
Each batch is checked by a taste panel and by lab instruments that measure texture, yield stress and viscosity. A jar of the finished product holds its shape until stirred. It is then pumped into jars or bottles and sealed.
Worth repeating
- Mayonnaise is thought to come from Mahon in Menorca, during the French occupation in the Seven Years' War.
- In 1815 the chef Antonin Carême wrote of a cold magnonaise emulsified with egg yolk, the same year the word mayonnaise is first attested in English.
Back to the ground
Follow every input upstream and mayonnaise starts as these 19 raw sources.
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Sources
- Tetra Pak: How to achieve high-quality mayonnaise
- Admix: Addressing mayonnaise processing inconsistencies
- Mayonnaise
- Vinegar
Cite this page: "How mayonnaise is made." Assembly Line, 2026-11-03. https://assemblyline.org/make/mayonnaise