If your mayonnaise is too oily, whisk in a tablespoon of warm water or lemon juice. If it's too thin, slowly whisk in more oil, drop by drop, until it emulsifies.
Mayonnaise separates when the emulsion breaks down, usually due to adding oil too quickly or using ingredients at different temperatures. Here's how to fix it:
For Oily Mayonnaise (Separated):
Start Fresh: In a clean bowl, place 1 tablespoon of the broken mayonnaise. This will act as your base.
Add Water or Lemon Juice: Add 1 teaspoon of warm water or lemon juice to the base. The warmth helps re-emulsify the mixture.
Whisk Vigorously: Whisk the water/lemon juice and the base mayonnaise together until it forms a smooth, creamy paste.
Slowly Incorporate the Broken Mayonnaise: Very slowly, drop by drop, whisk in the remaining oily mayonnaise. As the emulsion starts to form, you can gradually increase the rate at which you add the oily mixture.
Adjust Consistency: If needed, add a tiny bit more water or lemon juice to reach the desired consistency.
For Thin Mayonnaise:
Continue Whisking: Keep whisking the mayonnaise vigorously.
Add Oil Slowly: Add more oil, drop by drop, while continuously whisking. The key is to add the oil very slowly to allow the emulsion to form properly.
Increase Oil Flow Gradually: Once the mayonnaise starts to thicken, you can gradually increase the flow of oil to a very thin stream, but still whisking constantly.
Check Consistency: Stop adding oil when the mayonnaise reaches your desired thickness.
To prevent mayonnaise from separating in the first place, ensure all your ingredients (eggs, oil, lemon juice/vinegar) are at room temperature. This helps them emulsify more easily.