Phase one: the enzymatic phase
Nothing visible happens at first. Chymosin is working through the milk, cleaving kappa-casein micelle by micelle. The milk still looks like milk.
Phase two: aggregation
Once enough of the stabilising layer is gone, micelles start linking. This is where you see thickening, then flocculation, then a gel that spans the vat.
What speeds each phase
| Condition | Effect |
|---|---|
| Higher enzyme dose | Shortens the enzymatic phase |
| Temperature within the style's range | Supports both phases; cold milk slows aggregation sharply |
| Lower pH | Generally speeds coagulation |
| Available calcium | Supports aggregation and curd firmness |
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