How to Choose a Moisture Analyzer: A Buyer's Guide for the UAE & GCC

Loss-on-drying (LOD) moisture analyzers: how they work

LOD moisture analyzers heat a sample on an integrated balance pan using a halogen heating element and measure the weight loss continuously until a stable endpoint is reached. The result is expressed as % moisture content (weight of water / original weight × 100). Modern halogen moisture analyzers using A&D Japan's Secondary Radiation Assist (SRA) technology achieve uniform heat distribution without hotspots, enabling reproducible results in 3–8 minutes for most sample types.

LOD is the most practical method for routine QC moisture determination in food, pharmaceuticals, chemicals, and building materials. It correlates well with reference oven drying methods (ISO 712, AOAC methods, BP/USP procedures) for most matrices. The key advantage is speed: where oven drying requires 1–24 hours, an LOD moisture analyzer returns a result in minutes.

Choosing the right resolution

A&D Japan's moisture analyzer range spans four resolution levels. The MS-70 (0.001% resolution, 0.001 mg balance) is the research-grade instrument for pharmaceutical QC and materials science where the last digit of moisture percentage is meaningful. The MX-50 (0.001% resolution, 0.1 mg balance) provides the same moisture resolution at lower cost, suitable for pharmaceutical production floor use. The MF-50 (0.01% resolution) covers most food industry and chemical QC applications. The ML-50 (0.1% resolution) is the entry-level screening instrument for routine production use.

Resolution selection should follow the same minimum sample weight logic as balance selection: the moisture percentage resolution you select must be appropriate for the moisture range you are measuring. For a product with 5–15% moisture, 0.01% resolution (MF-50) is more than adequate. For a hygroscopic API at 0.05–0.15% moisture, 0.001% resolution (MS-70 or MX-50) is required to detect meaningful variation.

When to use Karl Fischer titration instead

Karl Fischer (KF) titration is the gold standard for very low moisture content — typically below 0.1% — in liquids, gases, and samples that cannot be heated without degradation. KF measures total water content (free and bound) rather than loss-on-drying, making it more accurate for moisture-sensitive samples such as oils, solvents, and certain APIs. If your specification requires moisture below 0.1% in a temperature-sensitive product, KF titration is the required method, not LOD.

For most food, chemical, and routine pharmaceutical applications where moisture is above 0.1% and the sample tolerates heating at 50–200°C, LOD with a halogen moisture analyzer is faster, lower-cost, and easier to operate than KF titration. AND Gulf can advise on the correct method for your specific application.

Drying temperature settings

Most halogen moisture analyzers allow drying temperature to be set between 50°C and 200°C. The correct setting depends on the sample matrix: food products typically dry at 105°C, pharmaceuticals at 105°C (USP ⟨731⟩) or method-specific temperatures, spices and volatile-rich samples at 80–90°C to avoid volatilising non-water components. A&D moisture analyzers support multiple saved drying programs, allowing different products to be tested without manual temperature entry.