Near-Infrared (NIR) spectroscopy has transformed quality control in the grain and milling industry. What once required a panel of separate wet chemistry tests — each taking hours and consuming reagents — can now be accomplished in seconds with a single, non-destructive scan. Understanding what NIR can and cannot do is essential for any modern grain handler or flour miller.

The Principle of NIR Analysis

NIR instruments illuminate a sample with near-infrared light across a range of wavelengths. Different chemical bonds in the sample — those of protein, moisture, starch, and fat — absorb light at characteristic wavelengths. By measuring the reflected or transmitted light pattern, the instrument uses mathematical calibration models to predict the composition of the sample.

The result: protein content, moisture, starch, ash, and even wet gluten estimates — all from a single measurement taking less than 30 seconds and requiring no sample preparation beyond ensuring the grain is representative.

Key Applications in the Grain Chain

• Intake quality control: Screen incoming grain loads for protein and moisture at the elevator.
• Milling optimisation: Blend wheat lots to achieve target flour protein specifications.
• Flour release control: Verify flour quality before release to bakery customers.
• Feed production: Analyse protein and energy content of feed ingredients.

Calibration: The Critical Factor

An NIR analyser is only as good as its calibration. Calibrations are built using reference samples with known values determined by reference methods (e.g., Kjeldahl for protein, Karl Fischer for moisture). Using the wrong calibration — one built for soft wheat on hard wheat, for instance — produces systematically incorrect results. Always verify that your instrument’s calibration matches your grain type and origin.

Leading Instruments on the Market

Perten DA 7250, Foss Infratec, and Bruker instruments are among the most respected NIR platforms in the industry. At Fuhler Labor, we offer pre-owned NIR analysers with documented calibration histories, allowing mills to access this technology at a fraction of the new price.