Name: Hollandaise Sauce
Ingredients: 1 tablespoon minced parsley; ¾ tablespoon lemon juice; ½ teaspoon onion juice; 1 beaten egg yolk

Why it works: Parsley and lemon match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and 14,037 recipes mention both. Both carry beta-phellandrene, which smells minty, terpene. The science ↓

Hollandaise Sauce

Ingredients

1 tablespoon minced parsley
¾ tablespoon lemon juice
½ teaspoon onion juice
1 beaten egg yolk

Directions

In a saucepan, combine the drawn butter sauce with minced parsley, lemon juice, onion juice, and beaten egg yolk.
Stir over low heat for a moment until well mixed.
Serve immediately with fish.

Recipe from a historical cookbook (Internet Archive).

Transcribed from a scanned cookbook and modernised for today's kitchens. Where the book gave no heat or time, or said "a moderate oven", the temperatures and times here may be modern equivalents rather than the book's own figures.

Explore the science

The flavor team

The pairs that carry this dish. Each one is judged two ways: how much aroma chemistry they share, and how many recipes mention both.

Parsley + lemontop 1% of all pairs

Aroma overlapstrong

Mentioned together14,037 recipes

Shared aroma: beta-phellandrene (minty, terpene).
Parsley + oniontop 9% of all pairs

Aroma overlapmoderate

Mentioned together25,843 recipes

Shared aroma: 2,4-decadienal (seaweed).
Lemon + eggtop 19% of all pairs

Aroma overlaplow

Mentioned together44,316 recipes

Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
Lemon + oniontop 19% of all pairs

Aroma overlapmoderate

Mentioned together15,646 recipes

Shared aroma: decanal (soap, orange peel).
Parsley + eggtop 21% of all pairs

Aroma overlapmoderate

Mentioned together18,765 recipes

Shared aroma: 2,4-decadienal (seaweed).

Lemon and egg share little aroma chemistry, yet 44,316 recipes mention both: they likely work on texture and structure more than aroma.

Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs

Flavor stand-ins for the onion

How well each one fits the dish's main ingredients (parsley, lemon, egg):

Shallotbetter flavor fit
Spinachbetter flavor fit
Asparagusbetter flavor fit
Onionthe original

Fit is the average pairing score against parsley, lemon, egg. Candidates are from the same food group and used in at least 100 recipes. This compares flavor only: it does not check the job the ingredient does in the dish (bulk, moisture, acidity, structure).