Determination of Lactose in Bakery Products and Baked Goods

CDR FoodLab® allows you to determine lactose on bakery products and baked goods in order to verify the exact residual amount of lactose present in the lactose-free products.

The sample preparation is very easy and it is carried out in 4 easy steps:

  • Grind the sample and weigh it as it is written in the method
  • Add a specific amount of water
  • Homogenise
  • Centrifuge and collect the supernatant to carry out the analysis

In 10 minutes with this easy method you can obtain affordable and precise results as you obtain with the reference method (HPLC) that needs chemical skill and expertise being also very time consuming.


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.

Correlation curve

Here below we have the correlation of the results obtained doing the analyses with CDR FoodLab® and the reference method on low lactose milk. The correlation R2= 0,9882 is great considering the difficulty of the reference method.

Correlation chart Analysis of lactose on CDR FoodLab® delactosed milk and HPLC method (ISO 22662). Correlation R² = 0.9882

In the case of finished products, with a sample preparation, a limpid supernatant containing lactose  is obtained. The analysis is carried out on this supernatant.

Reagent test Kits

Measuring range

AnalysesMeasuring rangeResolutionRepeatability

The Analyzers CDR FoodLab® for a complete quality control on bakery products, baked goods, snacks and spreads


CDR FoodLab®

  • Complete analysis panel, supplied already configured
  • Up to 16 determinations simultaneously
  • Possibility of carrying out analyses of the same sample
  • Integrated printer
  • Full connections (LAN - USB - Bluetooth barcode/QR code reader)

CDR FoodLab® Jr

  • Partial analysis panel, supplied configured with 3 analyses of your choice, implementable
  • Up to 3 determinations simultaneously
  • Wireless connection to external printer
  • USB connections