Name: Butter, to Preserve
Ingredients: 2 parts common salt; 1 part loaf sugar; 1 part saltpetre

Butter, to Preserve

Ingredients

2 parts common salt
1 part loaf sugar
1 part saltpetre

Directions

Prepare the cure

Pound the salt, sugar, and saltpetre together in a mortar until well combined.

Pack and preserve

Pack the butter into glazed earthen pots.
Sprinkle the salt mixture over the butter to preserve it.

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

What each ingredient does

Common salt: Draws out moisture and acts as the main preservative in the butter.
Loaf sugar: Balances the salt's sharpness and adds a mild sweetness to the butter.
Saltpetre: Helps inhibit spoilage and supports the preserving action of the salt.

“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.