Determination of Lactose in milk

The chemical analysis of the milk and dairy products  for quality control in every stage of the production chain with CDR FoodLab

CDR FoodLab allows to make lactose test in milk at production line, without skilled staff help and in accordance to the reference method (Fehling), a volumetric method that instead requests training, special skills and so much time at disposal. With a simple analytical kit, 10 minutes of time and few steps you can obtain reliable and accurate results.

Analyzers for determining Lactose in milk and dairy products


  CDR FoodLab Touch version for performing a range of tests in milk and a variety of dairy products CDR FOODLAB TOUCH CDR FoodLab Touch version for performing a range of tests in milk and a variety of dairy products CDR FOODLAB JUNIOR
Analyses e-Fructosyl Lisine
L-Lactic Acid
Alkaline phosphatase (ALP)
Hydrogen peroxide
Urea Milk Nitrogen (MUN)
Peroxide value (PV)
Free Fatty Acids (FFA)
Configuration with tailored panel of analyses
Simultaneous Sample Analyses 16 3
Multiple Analyses on a Sample si

It is not necessary skilled staff nor a laboratory for the analysis.
Results are correlated with reference method results.
It is free of service and maintenance cost.
With the same analyzers you can also perform analysis of egg, tomato, vegetable purees, cheeses and fats.

Calibration curve

The calibration curve was performed with lactose standard solutions.

Lactose calibration curve with CDR FoodLab milk ana dairy analysis system


Test type: End Point
Time of test: 10 minutes
It is possible to carry out several test sessions with a maximum of 16 samples.
Calibration can be performed by aligning the test to reference values.

Test principle

Lactose is a disaccharide sugar that is found in milk and is formed from galactose and glucose. Lactose makes up around 4.5~5% of milk (by weight). The enzyme lactase is essential for digestive hydrolysis of lactose in milk. Deficiency of the enzyme causes lactose intolerance.

Lactose is split in glucose and galactose. Glucose reacts with a phenolic compound through an enzymatic reaction, with peroxidase, and forms a pink coloured complex. The absorbance of the complex is read at 505 nm, and the value is directly proportional to the concentration of lactose in the sample.

Composition of the Kit and Reagents

Reagent test kit *300015 suitable for 100 tests, contains:

  • 1 box includes: 10 x reagent test kit *300010

Reagent test kit *300010, suitable for 10 tests, contains:

  • R1: package with 10 pre-filled cuvettes with bufferr.
  • R1a: bottle with enzymatic solution
  • R2: bottle with starter reagent

Processing – Sample volume – Measuring range

Milk: Dilute 1 part of milk + 10 parts of water. E.g. take 100 uL of milk and add it to 1mL of distilled water
Mozzarella: weight 10 grams of mozzarella and add 100 mL of distilled water. Mix in a Stomacher for about 3 minutes. Take the filtered solution to test

Measuring range
(% lactose)
Sample volume Resolution
(% lactose)
0.01 – 0.25 5 µL diluited 0.01 0,005%

Reagent developed by CDR S.r.l - ISO 9001 certified company


Click and Discover more about CDR FoodLab: Tests in few minutes, reference methods compliant. Easy to use also by unskilled staff

Lactose was last modified: July 11th, 2016 by CDR s.r.l.