Quantitative Characterization of Feed and Agricultural Samples Using a Handheld Near-Infrared Analyzer

Background Near-infrared (NIR) spectroscopy has been widely accepted for use in the food and agricultural areas, beginning with the work of Karl Norris at the USDA to develop quality methods for agricultural products. However, since NIR spectra are overtones and combinations of fundamental IR spectra, the peaks tend to lose definition and broaden, representing general features due to CH, NH and OH stretch and bend frequencies, as contrasted to their fundamental frequencies that define IR. Thus, it was not until mathematical and computer modeling of NIR spectroscopy was utilized, that information could be obtained from NIR. With the implementation of chemometrics methods, a valuable tool for differentiation and quantification of agricultural and food components became available. Coupled with the reduced requirement for sample preparation, one of the major strengths of NIR and the implementation of NIR in a portable, handheld unit such as the Thermo ScientificTM microPHAZIRTM analyzer, NIR spectroscopy and the subsequent identification and quantification of food, feed and agricultural samples can be taken from the laboratory directly to the field or warehouse.