Name: Vinegar
Ingredients: 1 lb coarse brown sugar; 1 gallon water; 1 thick slice of bread; yeast

Why it works: Sugar and bread are a kitchen classic. They rank in the top 32% of all ingredient pairs, and cooks put them together in 8,638 recipes. Both carry 2-nonenal, which smells fatty, green. The science ↓

Vinegar

Ingredients

1 lb coarse brown sugar
1 gallon water
1 thick slice of bread
yeast

Directions

Prepare the sugar water

In a saucepan, combine 1 lb of coarse brown sugar with 1 gallon of water.
Boil for 15 minutes, skimming the surface as needed.
Remove the mixture from heat and let it cool until nearly cold.

Start the vinegar

Toast a thick slice of bread and spread yeast on it.
Add the yeast‑covered bread to the cooled sugar water.
The next day, transfer the liquid into a cask and cover the bung‑hole with a cloth.

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.

Sugar + breadtop 32% of all pairs

Smell alikelow

Cooked together8,638 recipes

Shared aroma: 2-nonenal (fatty, green).

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

What each ingredient does

Brown sugar: Provides the sugars that yeast converts into alcohol, which later becomes acetic acid.
Yeast: Ferments the sugar water into alcohol, the first step toward vinegar.
Bread: Carries the yeast so it can be added to the liquid evenly.

“What each ingredient does” and “The step that matters” were written by Claude from this recipe’s own method and reviewed in samples by CompKitchen.