Behr S5 Automated Kjeldahl Distillation and Titration System

Overview

The Behr S5 Automated Kjeldahl Distillation and Titration System is a high-precision, fully automated solution for quantitative nitrogen determination in accordance with ISO 8968, AOAC 981.10, AOAC 984.13, ASTM D1122, and USP <467>. Engineered for laboratories requiring regulatory compliance and reproducible results, the S5 implements classical Kjeldahl methodology—comprising digestion (performed separately on dedicated digesters), alkaline distillation under controlled steam conditions, and acid-base titration—to convert bound nitrogen into ammonia, which is then quantified via volumetric titration. Unlike semi-automated or manual systems, the S5 integrates programmable distillation timing, precise steam generation, and seamless bidirectional communication with external titrators—enabling end-to-end automation from distillate collection to final %N calculation. Its robust stainless-steel housing, thermally insulated steam manifold, and fail-safe condensate management ensure stable operation across high-throughput environments including food safety labs, agricultural research centers, pharmaceutical QC facilities, and environmental testing institutes.

Key Features

• Fully programmable distillation cycle (1–99 minutes) with adjustable steam intensity and condensation temperature control
• High-recovery alkaline distillation architecture achieving >99.5% nitrogen recovery across diverse matrices (cereals, dairy, meat, feed, soil, wastewater)
• Repeatability of ≤0.5% CV (RSD ≤1%) verified per ISO 5725-2 under routine laboratory conditions
• RS232 serial interface compliant with GLP/GMP data integrity requirements; supports audit-trail-enabled titrators (e.g., Metrohm 809/856, Hanna HI84532)
• LCD user interface with 100 preloaded method templates—including AOAC, ISO, and internal SOP configurations—and password-protected parameter editing
• Integrated cooling water flow monitoring and automatic shutdown upon flow interruption or overheating
• Modular design compatible with Behr’s behrotest® CAN Set KAS sample handling accessories for unattended batch processing

Sample Compatibility & Compliance

The S5 accommodates standard 100–500 mL Kjeldahl digestion tubes (including borosilicate glass and quartz variants) and supports both macro- and semi-micro digestion formats. It is validated for use with ammonium sulfate, urea, casein, and glycine reference standards per ISO 8968-1 Annex A. All operational parameters—including distillation time, base addition volume, and condensate temperature—are configurable to meet matrix-specific requirements defined in FDA Bacteriological Analytical Manual (BAM) Chapter 17, EU Regulation (EC) No 152/2009, and Codex Alimentarius Standard 202–1995. The system complies with IEC 61010-1 for electrical safety and meets CE marking requirements for laboratory equipment. Documentation packages include IQ/OQ protocols aligned with 21 CFR Part 11 readiness for regulated environments.

Software & Data Management

While the S5 operates as a standalone distillation unit with embedded firmware, its RS232 interface enables direct integration with third-party titration software (e.g., Metrohm tiamo™, Hanna HI902C PC Suite) for synchronized method execution and raw data export in CSV or XML format. All method parameters, run timestamps, operator IDs, and titration endpoints are logged locally on the device’s non-volatile memory. When paired with a 21 CFR Part 11-compliant titrator, full electronic records—including digital signatures, change history, and audit trails—can be generated without intermediary PCs. Data export supports LIMS integration via standard ASCII protocols, and calibration logs adhere to ISO/IEC 17025 traceability frameworks.

Applications

• Protein content determination in food and feed products (calculated as %N × conversion factor, e.g., 6.25 for cereals, 6.38 for dairy)
• Crude protein verification in animal nutrition studies and aquaculture feed formulation
• Nitrogen balance analysis in soil science and fertilizer efficacy trials
• Residual ammonium quantification in pharmaceutical excipients and active ingredients
• Wastewater treatment plant monitoring per EPA Method 351.2 and ISO 14253-1
• Method validation and reference material certification in national metrology institutes

FAQ

Does the S5 include an integrated titrator?
No—the S5 is a dedicated distillation module designed for interoperability with external titrators via RS232. This architecture ensures flexibility in titrant selection, endpoint detection (potentiometric, photometric, or pH-stat), and regulatory alignment.
Can the S5 be used with digestion systems from other manufacturers?
Yes—provided digestion tubes conform to DIN 12331 or ISO 8968 tube geometry specifications and sample transfer is performed using standardized Kjeldahl transfer funnels or automated handlers (e.g., behrotest® CAN Set KAS).
What maintenance is required for long-term accuracy?
Monthly cleaning of the steam generator chamber and condenser coil with 10% citric acid solution is recommended. Annual verification of steam pressure regulation and base dosing pump linearity is advised per ISO/IEC 17025 preventive maintenance schedules.
Is method validation support available?
Behr provides application notes, recovery validation datasets, and IQ/OQ templates upon request. Third-party validation services are coordinated through authorized distributors for GxP-aligned installations.