How do I rescue mayonnaise that has split?
The one rescue that reliably works on any broken emulsion, step by step — and the two situations where a simpler fix will do instead.
- Difficulty
- intermediate
- Time
- 8 min
- Read
- 4 min
Short answer
Stop whisking. In a clean bowl, whisk a fresh egg yolk, or a teaspoon of Dijon, or a tablespoon of warm water. Add one teaspoon of the split mayonnaise and whisk until thick. Then add the rest a tablespoon at a time, whisking each fully in. Nothing is lost and the volume comes back.
A split mayonnaise looks catastrophic — a greasy, curdled mess with oil pooling on top. It is entirely recoverable, and it recovers by exactly the same method every time. You are not repairing the broken emulsion. You are starting a new one and feeding the broken one into it, treating it as if it were oil.
What you'll need
- A second clean bowl
- A fresh egg yolk, or Dijon mustard, or warm water
- Whisk
Step by step
- Stop, and take the whisk out.Continuing to whisk a broken emulsion makes the oil droplets larger, not smaller. Every second of extra agitation makes the rebuild slightly harder.
- Pour the split mixture into a jug so you can add it in controlled amounts.You are going to be adding it teaspoon by teaspoon and then spoonful by spoonful. A jug with a spout makes that far easier than a bowl.
- Put a new starter in a clean bowl.Best: a fresh room-temperature egg yolk. If you do not want to use another egg: a teaspoon of Dijon mustard. If you want to add nothing at all: a tablespoon of warm water, which works more often than people expect. Whisk it for a few seconds.
- Add exactly one teaspoon of the split mixture and whisk until thick and smooth.This is the whole rescue. Do not add any more until this teaspoon has emulsified. If it goes thick and glossy, everything from here is mechanical.
- Add the rest a tablespoon at a time, whisking each addition in completely.Exactly as if it were oil going into a fresh mayonnaise. The volume rebuilds in front of you and you finish with slightly more mayonnaise than you started with.
- Taste and correct.The rescue has added an unseasoned yolk, mustard or water, so the sauce is now underseasoned and slightly diluted. Salt, then acid, then taste again.
Tips
- Warm water alone as the starter is worth trying first if you are short of eggs. It dilutes the sauce slightly but it costs nothing to attempt.
- A stick blender in a narrow jug is very good at rebuilds because it shears the mixture right at the bottom where it starts.
- If the split sauce has been sitting for an hour, put it somewhere warm for a few minutes first. A cold, semi-solid split mixture is difficult to add in controlled amounts.
- A hollandaise that split from heat must be cooled first — this same sequence otherwise applies to it unchanged.
Common mistakes
- Whisking the split sauce harder and faster — There is no emulsifier available to coat new droplet surfaces. Agitation alone cannot create an emulsion.
- Adding the split mixture in a stream during the rebuild — You are repeating the mistake that caused the split. The first spoonful sets up the new emulsion and it needs the same care as the first drops of oil.
- Throwing it away — It is a functioning ingredient. Even if you do not want to rebuild it, split mayonnaise stirred into a potato salad, a coleslaw or a dressing behaves fine.
If it doesn't work
It split and the bowl feels cold
Cause: Temperature mismatch between yolk and oil, which is the usual cause of a cold split — Fix: Before rebuilding, try standing the bowl in warm water and whisking hard for a minute. A cold split will sometimes come back with no new emulsifier at all.
It split just as the last of the oil went in
Cause: The oil has exceeded what the yolk can coat — Fix: Rebuild on a fresh yolk. Do not add any more oil to the rebuilt sauce — it is already at the limit for the emulsifier now present.
The rebuild will not take even the first teaspoon
Cause: Too much split mixture went in at once, or the starter is cold — Fix: Start a third bowl with a yolk and half a teaspoon of warm water, whisk it properly, and add a quarter teaspoon at a time to begin with.
Questions people ask
Does hot water work as well as an egg yolk?
Water is not an emulsifier, so it does not raise the ceiling on how much oil the sauce can hold — but the split mixture still contains its original yolk, and giving that yolk a fresh water phase to work in is often enough to let it re-emulsify. It works most of the time and it is the first thing to try. If it fails, a fresh yolk almost always succeeds.
Why does adding the whole lot back at once never work?
Because the new emulsion has to be built droplet by droplet, just as the original was. Adding the whole split mixture to one yolk gives you a large volume of loose oil and a small amount of emulsifier trying to cover it, which is precisely the state you are trying to escape.