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Rennet Dosage

How Much Rennet Should You Use?

Short answer

Start from the dosage stated on your product label, then adjust so you hit the set time your cheese style calls for. Dosage is not a single universal number: it depends on the coagulant's clotting strength, your milk, temperature, pH and the style you are making.

By Bixa Products, Editorial teamUpdated July 30, 20268 min readReviewed by Luis

Dose to a target set time

Professional practice is to decide the set time the style needs, then dose to reach it. Fresh cheeses and pressed cheeses are not managed the same way, and the flocculation and clean-break points you are aiming for differ accordingly.

What changes the dosage you need

VariableEffect on the set
Coagulant clotting strength (IMCU)Higher activity means less product per litre
Milk protein and calciumLeaner or lower-calcium milk generally sets more slowly and softer
TemperatureBelow the style's range, coagulation slows markedly
pH at additionA lower pH generally speeds coagulation
Heat treatment of the milkHigh-heat treatment can weaken curd formation
Product age and storageActivity declines with age and warm storage

A responsible way to dial it in

  1. Fix everything you can: same milk source, same temperature, same procedure.
  2. Dose at the label recommendation for one batch and record the flocculation and clean-break times.
  3. Change dosage by a small increment on the next batch — nothing else.
  4. Repeat until your set time is where the style needs it, then write down the settings.

Bixa dosage guidance

Technical information to be supplied by Bixa.Product-specific dosage tables for Bixa coagulants.

Frequently asked

Should I add more rennet if my curd was weak last time?

Not as the first step. Check milk heat treatment, temperature, pH and coagulant age first. Increasing dosage to compensate for a different problem tends to create a new one.

Does dosage change when I scale up?

Dosage per litre stays the reference, but mixing, temperature uniformity and timing become harder at volume — which is often what actually changes your results.

About the author

Bixa ProductsEditorial 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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