Cheesemaking Science

What Determines Curd Firmness?

Short answer

Curd firmness is determined by milk protein and calcium content, temperature, pH, coagulant dosage and how long the gel is left to develop before cutting. No single one of these controls it on its own.

By Bixa Products, Editorial teamUpdated April 26, 20265 min read

Variable	Firmer curd	Softer curd
Milk protein/calcium	Higher	Lower
Temperature	Within style range	Below style range
Time after clean break	Longer	Shorter
Heat treatment	Standard pasteurization or raw	Ultra-pasteurized
Coagulant dosage	Higher (with trade-offs)	Lower

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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