{
  "key": "Emulsion",
  "value": "A stable mixture of two liquids that do not naturally combine — usually fat and water — held together by a third ingredient such as egg yolk, mustard or starch. Mayonnaise, vinaigrette, hollandaise and a carbonara sauce are all emulsions. They break when overheated or when the fat goes in too fast, which is why such sauces want gentle heat, steady whisking and, for pasta, a splash of the starchy cooking water."
}