24: Egg Yolk Animation Video
Transcript:
Technique: Thickening with Egg Yolk (Tempering)
There are a number of ways to thicken sauces. One of these techniques uses egg yolk as a thickening agent.
When using egg yolks to thicken hot sauces, care must be taken to avoid curdling. Curdling occurs when the liquid and solid portions of eggs or milk separate and create an unappealing, clumpy product rather than a smooth, homogenous one. If egg yolks are added directly into hot sauce, they are likely to curdle and ruin the sauce.
To avoid curdling, first mix the egg yolks with a small amount of chilled cream. This mixture is called a liaison.
Next, add a small amount of the hot sauce into the liaison.
Now the combined cream, egg, and sauce mixture can be added back into the pot of hot sauce. This process is called tempering.
Once the yolk mixture is added, cook the sauce slowly while stirring constantly.
The sauce will thicken between 160°F and 179°F (71°C and 82°C). If it reaches temperatures above 180°F (82°C), the sauce may curdle and thin out.