Cheesemaking Science

Understanding Curds and Whey

Short answer

Curd is the protein-and-fat gel formed when milk coagulates; whey is the liquid released as that gel contracts. Watching whey colour and clarity is one of the fastest ways to read how a make is going.

By Bixa Products, Editorial teamUpdated April 30, 20265 min read

Syneresis: how cheese loses water

After cutting, the curd pieces contract and expel whey. How far this goes — driven by stirring, temperature and time — largely sets the moisture of your finished cheese, and therefore its texture and shelf life.

Reading the whey

Clear, greenish-yellow whey: normal separation.
Cloudy, milky whey: fines from cutting too early or stirring too hard.
Very slow whey release: check temperature, pH and curd firmness at cutting.

About the author

Bixa Products — Editorial team

Educational content written by the Bixa Products team, a family-owned cheesemaking ingredient company specializing in rennet and chymosin. Technical guidance is written conservatively: where a value depends on your milk, process or product, we say so instead of guessing for you.

Family-owned cheesemaking ingredient company
30+ years in the Latin American cheesemaking market
Specialists in rennet, chymosin and milk coagulation

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