Determination of Lactose in milk and dairy products



The chemical analysis of the milk and dairy products for quality control for every stage of the production chain with CDR FoodLabCDR FoodLab® 
 allows to perform lactose determination in milk in accordance to the reference method (Fehling), a volumetric method that requests training, special skills and so much time at disposal.

Instead with CDR FoodLab®    you can estimate the lactose in milk and dairy products with a simple analysis method, in 10 minutes. In few steps you can obtain reliable and accurate results.

The CDR FoodLab® method can work easily on liquid or solid samples. For the latter it is required a very quick sample pretreatment in order to extract the solution for the analysis.

The test is suitable for use on lactose free products, where a part or all the lactose has been broken down to glucose and galactose by the lactase enzyme, it is also suitable for products where lactose is normally present.

Analyzers for determining Lactose in milk and dairy products

 

  CDR FoodLab for performing a range of tests in milk and a variety of dairy products CDR FOODLAB® CDR FoodLab for performing a range of tests in milk and a variety of dairy products CDR FOODLAB® JUNIOR
Analyses Lactose
e-Fructosyl Lisine
L-Lactic Acid
Ammonia
Chloride
Alkaline phosphatase (ALP)
Peroxidase
Hydrogen peroxide
Milk Urea 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

Determination of Lactose content in lactose-free dairy products with CDR FoodLab® in-depth

CDR FoodLab method for the determination of Lactose content in lactose-free dairy productsIn this work the new method  for lactose determination, that is in CDR FoodLab®, is assessed in terms of reproducibility, accuracy and recovery.

New method and traditional enzymatic method are also taken into comparisonon adding determined aliquotes of lactose in reallactose-free matrices.

The new method, that is in CDR FoodLab®, appears to be much quicker and with a friendly use for everyone if it is compared to the tradional enzymatic kit. Read More

Calibration curve

The calibration curve was performed with lactose standard solutions.

Lactose calibration curve with CDR FoodLab milk ana dairy analysis system

 

Methods

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.

Reagent test Kits

The reagents are packaged in foil pouches containing 10 tubes useful to perform 10 analyses.

This is the minimum package that allows the use of CDR systems even to those who need to make a few analyses, thus not wasting reagents.

There are also boxes of 100 tests, however, packaged in 10 bags of 10 tubes containing the reagent.

Reagent test kit *300015 suitable for 100 tests 

Reagent test kit *300010, suitable for 10 test

The reagents have a shelf-life of 12 months.

Processing – Sample volume – Measuring range

Sample

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

Cheese, yogurt, cream: weight 10 gr of sample and add 100 mL of distilled water. Mix in a Stomacher for about 3 minutes. Take the filtered solution to test.

Measuring range
(g/100g)
Sample volume Resolution
(g/100g)
Repeatability
0.01 – 2 10 µL diluited 0.01 ±0.02
1.5 – 5.5 5 µL diluited 0.01 ±0.02

Download the CDR Kit Lactose_0,01-5,5% method in pdf format

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: November 27th, 2017 by CDR s.r.l.