A Guide to Raw Material Analysis Using near Infrared Spectroscopy

In this paper, we discuss the theory and principles behind the construction and validation of near infrared (NIR) spectroscopic libraries for raw material identification and qualification. The considerations we present for raw material library construction are based on precedents that appear in the literature and upon the experience of the authors. This treatise takes a holistic approach. The development of a raw material programme is delineated in a 12-step plan that will give the reader a comprehensive perspective. The limitations of commercial NIR libraries and the advantages of customised libraries are then briefly discussed. Finally, we describe the development and validation of a small raw materials library to illustrate the principles of library construction and validation.