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Rennet Dosage

What Does IMCU Mean?

Short answer

IMCU stands for International Milk Clotting Units. It is the standard way to express how much milk-clotting activity a coagulant has, which is what makes dosage comparable between products instead of guesswork.

By Bixa Products, Editorial teamUpdated February 18, 20265 min readReviewed by Luis

Why a unit is needed at all

Two bottles of liquid coagulant can look identical and differ substantially in clotting activity. Without a shared unit, 'one teaspoon per gallon' means nothing across products.

IMCU expresses activity per unit of product. A higher figure means more clotting activity in the same volume, so less product is needed for the same set.

How to use it in practice

  1. Read the IMCU figure and recommended dosage on your product label.
  2. Dose for your target set time, not for a number you read elsewhere.
  3. Record the set time you observe.
  4. Adjust in small steps, changing one variable at a time.

Bixa product strengths

Technical information to be supplied by Bixa.IMCU values for Bixa Liquid Microbial Rennet and Bixa Liquid Chymosin.

Frequently asked

Can I convert dosage between two coagulants using IMCU?

IMCU makes activity comparable, which helps as a starting point. Still run a trial batch: products differ in more than raw clotting units, and your milk and process will have the final say.

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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