Expansion of NIR Calibration for Soybean

Impact on Soybean Production and Value

Researchers throughout the US will be able to use the new calibration on multiple NIR platforms. The expanded range will improve their ability to measure and identify soybean seeds with a broad range of protein, oil, and carbohydrates to meet the needs of a broad range of end uses and provide increased value to growers and processors.

George Graef and Charles Hurburgh (2013)

Key Terminology

Near Infrared (NIR) is a range of wavelengths that are just beyond the visible light spectrum that humans can see

Study Objectives

The objective of this work is to extend the high and low ends of the range of the NIR calibrations for soybean seed protein and oil content currently used by public soybean breeders and other researchers working to improve soybean compositional quality.


The project was successful in expanding the range of NIR calibrations used for quick and accurate measurement of soybean seed protein and oil concentration. The new ranges were made possible by evaluation of the high protein and high oil soybean germplasm lines we developed at the University of Nebraska. The calibration can reliably measure soybean seed oil and protein ranging from about 30% to 60% Protein and 11% to 28.5% oil on a dry matter basis. The ranges that were used for calibration are listed below:

Range – 13% moisture basis
Protein: 24.72 (Low) to 52.08 (High)
Oil: 9.77 (Low) to 24.72 (High)

Range – dry (0% moisture) basis
Protein: 30.39 (Low) to 59.86 (High)
Oil: 11.23 (Low) to 28.41 (High)

Next Steps

The Nebraska soybean breeding program germplasm made the calibration expansion possible to the extremes for both protein and oil. The calibration will be useful to researchers throughout the US for quick and accurate, high-throughput measurement of soybean seed composition in their research and development programs to improve soybean compositional quality for end users for food, feed, fuel, and other industrial applications.