Near-Infrared Spectroscopy

Near Infrared Spectroscopy (NIRS) has been labelled as the “magic black box” for years. No other analytical technique can match the speed of analysis that can be completed in a matter of seconds, without destroying or even touching samples. The interaction of infrared light (700–2500 nm) with food products generates specific spectral fingerprinting related to the physical and, more importantly, chemical composition of food products. A basic understanding of the scientific principles behind this predictive analytical technique will empower researchers and professionals to develop food applications for any food product. The vast literature available demonstrates the flexibility of NIRS in predicting chemical composition (moisture, fat, protein, carbohydrates), but also in determining the best harvest time, or identifying adulteration or authenticity. A focus has been placed on understanding which scanning mode (reflectance, transmittance, transflectance, or interactance) is best suited for different products, also in relation to the cost of the instruments and optimization of the accuracy of predictions. With the progress in sensor technology, new instruments are entering the market, with a definite trend toward portability and miniaturization, lowering the costs and accessibility of this technology also in less developed countries.