FPD calibration sets

Freezing point depression (FPD) is a key quality marker for detecting dilution and safeguarding milk integrity. Because it reflects osmotic balance driven by lactose and minerals, FPD is the most sensitive routine indicator of added water or unintended dilution from cleaning solutions or condensate. Reliable FPD screening underpins fair payment, regulatory compliance, and stable processing yields. Mid-infrared (MIR) spectroscopy enables rapid, high-throughput FPD checks alongside other milk constituents in routine labs and plants.

To ensure accuracy, reproducibility, and harmonization of FPD results across instruments and sites, MIR analyzers like the DairySpec FT and FTS should be calibrated regularly using robust, traceable reference materials. That’s why Bentley Instruments has developed dedicated FPD calibration sets – precisely formulated mid-infrared SRMs (Standard Reference Materials), traceable to the cryoscopic reference method (e.g., ISO 5764|FIL 108) – to optimize analyzer performance and deliver consistent, reliable decisions over time.

Bentley Instruments’ FPD calibration sets are available in two formats:

• 20 raw cow’s milk samples, 40 mL each, covering 0.480–0.555 °H
• 11 raw cow’s milk samples, 60 mL each, covering 0.470–0.590 °H

These mid-infrared calibration standards are store at cold positive and contain a stabilizer to preserve sample integrity over time.

Specifically validated for FPD analysis in milk, these calibration sets provide optimal control of mid-infrared analyzers such as the DairySpec FT and FTS. They ensure long-term stability, enhanced analytical accuracy, and early detection of instrument drift.

Reference values for each calibration sample are established using the cryoscopic reference method in accordance with ISO 5764 | IDF 108.

Our FPD calibration sets are shipped monthly according to a predefined schedule. Each shipment is prepared in isothermal packaging with ice packs to maintain the cold chain and ensure optimal sample preservation. A sealed water bottle is included to monitor temperature stability upon delivery. All shipments are sent via express carrier for rapid and secure transport.