Novasina LabTouch-aw Desktop Temperature-Controlled Water Activity Analyzer

Overview

The Novasina LabTouch-aw is a precision desktop water activity (a_w) analyzer engineered for laboratories and production environments requiring traceable, thermally stabilized measurements across the full physiologically and microbiologically relevant range (0.030–1.000 a_w). Unlike conventional chilled-mirror or capacitance-based systems, the LabTouch-aw employs Novasina’s patented Resistive Electrolyte Measurement System (REMS)—a NIST-traceable, equilibrium-based method that directly quantifies the vapor pressure of water above a sample by measuring the electrical resistance of a highly stable, temperature-controlled electrolyte solution in dynamic vapor-phase equilibrium. This principle eliminates hysteresis, drift, and cross-sensitivity to volatile organic compounds (VOCs), delivering inherently high reproducibility (<0.001 a_w repeatability) and long-term stability without routine recalibration. The integrated Peltier-based temperature control (15–30 °C, ±0.1 °C) ensures compliance with standardized test conditions specified in ISO 21807, AOAC Official Method 975.34, and USP , making it suitable for regulatory submissions, shelf-life modeling, and HACCP-critical process validation.

Key Features

• Patented REMS sensor technology—no moving parts, zero consumables, lifetime probe stability
• Active temperature regulation (15–30 °C) with real-time monitoring and digital PID control
• High-resolution 7-inch full-color TFT touchscreen interface with intuitive icon-driven workflow
• Integrated NIST-traceable calibration verification using long-life saturated salt standards (e.g., LiCl, MgCl₂, NaCl, KCl)
• Optional VOC filtration kits (activated carbon + hydrophobic membrane) for samples containing ethanol, acetic acid, or essential oils
• Compact benchtop footprint (1 kg net weight) with low power consumption and silent operation
• Compliance-ready audit trail logging (time-stamped a_w, T, RH%, measurement duration, operator ID)

Sample Compatibility & Compliance

The LabTouch-aw accommodates solid, semi-solid, paste, powder, and liquid samples in standard 35 mm or 55 mm sample cups—compatible with common laboratory workflows in food R&D, pharmaceutical stability testing, and nutraceutical QC. Its REMS architecture is insensitive to sample color, opacity, viscosity, or particulate load, enabling direct measurement of chocolate, cheese, dried herbs, baked goods, lyophilized APIs, and fermented products without pretreatment. Regulatory alignment includes full support for FDA 21 CFR Part 11-compliant data integrity when paired with Novasina’s optional LabSoft software (electronic signatures, role-based access, immutable audit trails). Instrument performance meets requirements outlined in ISO/IEC 17025 for accredited testing laboratories and satisfies GMP/GLP documentation standards for pharmaceutical and dietary supplement manufacturing.

Software & Data Management

LabSoft PC software (Windows-compatible, optional) provides advanced data acquisition, statistical analysis (mean, SD, CPK), trend charting, and automated report generation in PDF or Excel format. All measurements are timestamped and stored with full metadata—including ambient lab temperature, user ID, calibration status, and filter usage history. Data export supports CSV and XML formats for LIMS integration. Firmware updates are performed via USB or network connection, ensuring ongoing compliance with evolving pharmacopeial revisions and internal SOPs. Remote monitoring capability enables centralized oversight across multiple instruments in distributed production facilities.

Applications

• Food safety validation: Determining critical a_w thresholds for pathogen inhibition (e.g., Staphylococcus aureus growth limit at 0.86 a_w, Clostridium botulinum proteolytic type at 0.97 a_w)
• Shelf-life prediction: Correlating a_w with lipid oxidation rates, Maillard browning kinetics, and microbial lag-phase extension
• Pharmaceutical excipient qualification: Monitoring hygroscopicity of lactose, microcrystalline cellulose, and amorphous polymers under controlled T/RH
• Process optimization: Validating drying endpoints in spray drying, freeze-drying, and fluidized bed granulation
• Regulatory testing: Supporting FDA Food Safety Modernization Act (FSMA) preventive controls and EU Regulation (EC) No 2073/2005 microbiological criteria

FAQ

How does the REMS principle differ from chilled-mirror dew point measurement?

REMS measures vapor-phase water activity via resistive equilibrium of a reference electrolyte, eliminating condensation artifacts, mirror contamination, and thermal lag—making it more robust for routine QC and high-humidity samples.
Is temperature control mandatory for every measurement?

Yes—ISO 21807 and USP require measurement at a defined, stable temperature (typically 25 °C); the LabTouch-aw’s active thermal regulation ensures compliance without external incubators.
Can the instrument measure samples with high ethanol content, such as spirits or tinctures?

With the optional VOC filter kit installed, the LabTouch-aw maintains accuracy for ethanol concentrations up to 40% v/v by preventing sensor interference and condensate formation.
What calibration standards are supplied, and how often must they be replaced?

Two long-life saturated salt standards (LiCl and NaCl) are included—certified for ≥24 months under sealed storage; no field recalibration is required between annual verification checks.
Does the system support 21 CFR Part 11 compliance out of the box?

Hardware-level audit trail logging is built-in; full Part 11 compliance (electronic signatures, system validation protocols, access controls) requires LabSoft software and site-specific IQ/OQ documentation.