Name: Colouring for Jellies, Creams, Ices, and Cakes
Ingredients: ⅓ cup water; 20 grains cochineal; 20 grains alum; 20 grains cream of tartar (finely pounded); saffron (for yellow); handful of spinach leaves (for green)

Why it works: Saffron and spinach match in chemistry and in kitchens. They rank in the top 2% of all ingredient pairs, and cooks put them together in 149 recipes. Both carry nonanal, which smells fat, citrus. The science ↓

Colouring for Jellies, Creams, Ices, and Cakes

Ingredients

Directions

Boil water slowly in a saucepan.
Add cochineal, alum, and cream of tartar; reduce to half.
Strain the mixture and store in a small bottle.
For yellow, use an infusion of saffron.
For green, boil spinach leaves in a covered saucepan, then press to extract juice.

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 their aromas overlap, and how often cooks already put them together.

Saffron + spinachtop 2% of all pairs

Smell alikestrong

Cooked together149 recipes

Shared aroma: nonanal (fat, citrus).
Cream + spinachtop 17% of all pairs

Smell alikemoderate

Cooked together1,130 recipes

Shared aroma: octanal (fat, soap).
Cream + saffrontop 20% of all pairs

Smell alikelow

Cooked together243 recipes

Shared aroma: acetic acid (sour, vinegar).