Chymosin 101

Chymosin for Aged Cheese

Short answer

Cheesemakers often choose chymosin for pressed and aged cheeses because it is specific in how it acts on milk protein, which matters over weeks or months of ripening. Ripening results still depend on milk, culture, moisture, salt, pH and ageing conditions.

By Bixa Products, Editorial teamUpdated March 1, 20266 min readReviewed by Luis

Why the coagulant matters longer in aged cheese

In fresh cheese the coagulant's job is essentially finished within hours. In an aged cheese, residual coagulant activity stays in the curd and participates in protein breakdown throughout ripening. That is why dosage discipline matters more in aged styles.

The bitterness question

Bitterness in ripened cheese is often discussed in relation to excessive coagulant, but it can also come from culture selection, moisture, salt distribution, pH and ageing temperature. Treat it as a process investigation, not a single-cause verdict.

Bixa guidance for aged styles

Technical information to be supplied by Bixa.Aged-cheese dosage and application guidance for Bixa Liquid Chymosin.

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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