How to Choose the Right Kjeldahl Distillation Unit for Your Lab

Nitrogen and protein analysis are cornerstones of quality control in industries from food to environmental science. At the core of these analyses is the Kjeldahl method, still regarded as the gold standard for its accuracy and adaptability. But not all Kjeldahl analyzers are created equal—and choosing the right system can make a world of difference in lab efficiency, data integrity, and throughput.

VELP Scientifica brings decades of analytical expertise to laboratories worldwide, offering a full suite of Kjeldahl-based solutions, from digestion to distillation and titration. Our UDK Series distillers are designed to cover every need, from basic to fully automated analysis, all while ensuring compliance with international standards like TKN, TVBN, phenols, Devarda, cyanides, and more.

Let’s explore how to choose the right unit for your lab’s specific demands:

Need Maximum Throughput and Zero Supervision? Go Fully Automated.

UDK 169 is the flagship model for high-productivity labs. With a fully automatic workflow—from distillation to colorimetric titration—it works seamlessly with the AutoKjel autosampler, analyzing samples autonomously and storing results without the need for manual intervention.

Why labs love it:

• Hands-off operation with continuous sample analysis
• Colorimetric titration (AOAC-compliant) ensures top-tier accuracy
• Fast turnaround thanks to online titration and real-time calculations
• Built-in reagent dosing, residue removal, and steam regulation
• 7” digital display and Smart User Interface for simplified control
• Remote monitoring and data storage via ERMES Cloud Platform

Seeking Full Automation, but with a Choice of Titration?

Looking for automation with different titration preferences? The UDK 159 features an integrated, AOAC-approved colorimetric titrator, while the UDK 149 is compatible with an external potentiometric system — ideal for labs that already rely on specific titration protocols.

Both units offer:

Fast, automated workflows

• High repeatability and accuracy
• Programmable steam output and reagent dosing
• Smart waste removal and intuitive interfaces
• ERMES connectivity for digital management

These models offer flexibility for those who want a powerful system tailored to their preferred titration method.

Prefer Control with a Touch of Automation? Choose Semi-Automatic.

Not every lab needs full automation. UDK 139 and UDK 129 offer reliable semi-automatic options that strike a balance between manual control and smart features.

• UDK 139 comes with a 7” touchscreen, programmable steam settings, and ERMES compatibility
• UDK 129 offers essential functionality with robust performance and user-friendly design

Ideal for labs with low to medium sample volumes, these units prioritize safety, durability, and ease of use, while maintaining analytical precision.

Which Kjeldahl Unit is Right for You?

Every laboratory is different—and your Kjeldahl solution should reflect that. Whether you need complete automation, flexible titration, or a compact, cost-effective unit, VELP has an analyzer to match your goals.

➡️ Download the full UDK Series brochure for detailed specifications, comparison tables, and everything you need to make an informed decision.