Determination of Lactose in milk
CDR FoodLab® allows to make lactose test 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 perform the test with a simple analysis method, in 10 minutes and in few steps you can obtain reliable and accurate results.
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® |
 CDR FOODLAB® JUNIOR |
|
|---|---|---|
| Analyses | e-Fructosyl Lisine L-Lactic Acid Ammonia Chloride Alkaline phosphatase (ALP) Peroxidase Hydrogen peroxide Milk Urea Nitrogen (MUN) Lactose Peroxide value (PV) Free Fatty Acids (FFA) |
Configuration with tailored panel of analyses |
| Simultaneous Sample Analyses | 16 | 3 |
| Multiple Analyses on a Sample |  |
– |
Determination of Lactose content in lactose-free dairy products with CDR FoodLab® in-depth
In this work a new improvement for lactose determination 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.
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 (% lactose) |
Sample volume | Resolution (% lactose) |
Repeatability |
|---|---|---|---|
| 0.01 – 2 | 10 µL diluited | 0.01 | 0,005% |
| 0.1 – 5.5 | 5 µL diluited | 0.01 | 0,005% |
Download the CDR Kit Lactose_0,01-5,5% method in pdf format
