Hollandaise (Warm Butter Emulsion) — Cross-Reference

Sauce

What it is

Hollandaise is a warm O/W emulsion of clarified or whole butter into egg yolks loosened with acid and a little water, the foundational warm emulsion of the French repertoire and the parent of béarnaise, choron, maltaise, and mousseline.

Why it lives in S-01

Because hollandaise and the warm-butter emulsions form a tightly related technical cluster — clarified-butter ratios, the sabayon whisking stage over gentle heat, the narrow safe-temperature window — they are catalogued in full under S-01: Warm Emulsion Sauces of the French Repertoire. The complete entry there covers the science, the rescue, and the derivative family.

The one science point that belongs here

Hollandaise is the clearest everyday demonstration of why temperature breaks emulsions: the egg yolks must be cooked just enough to thicken (form a sabayon) but kept below the ~85 °C / 185 °F threshold where yolk proteins coagulate. Too cool and it never thickens; too hot and the proteins scramble, ejecting the butter as the emulsion shatters. It is the canonical warm-emulsion tightrope.

Reference notes

See: S-01 Warm Emulsion Sauces (full entry).
Cross-links: Emulsification (Foundation) · Béarnaise · Clarified Butter · Eggs Benedict (Dish).

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