An increasing number of portable instruments based on near-infrared spectroscopy have now been on the market for a decade. This technique, which has long been used mainly in the laboratory, is evolving to bring its use closer to the sample, and closer to the user of the result provided. How good are these instruments? Are they of equal quality?
What distinguishes the various portable instruments is their compact appearance, ease of use, the fact that they can be controlled via a smartphone (or even a watch) with a wired or wireless connection, and their low cost compared with conventional infrared devices. Some can also be adapted to include predictive models for the simultaneous determination of various product parameters or criteria, or can be coupled to a GPS device enabling geolocation of measurements, or connected to the cloud in order to offer custom-made solutions, or directly embedded into a smartphone. These instruments make use of sensors that bring new technologies and strategies into play, to generate part of the near-infrared spectrum resulting from the interaction of light with matter.
The CRA-W has been evaluating some of these portable instruments for several years. This is because they must be subject to rigorous evaluation to ensure that they represent a real opportunity for those working in the world of agriculture and food. Furthermore, they require optimisation of the measurement protocols in order to take into account the heterogeneity of the products, adaptation regarding the presentation of the sample, and the development of a calibration strategy adapted to the new technologies implemented. The CRA-W is also working on the most suitable methodology for transferring databases constructed decades ago, with laboratory devices, to portable instruments.
These portable devices will obviously play an increasing part in our farms and businesses, to determine the key parameters necessary to bring quality control as close as possible to the products. They will form an integral part of future decision-making tools, including precision food production, raw material quality control, batch segmentation, product traceability and fraud detection. Due to their design, the new technologies involved can readily act as sensors in our processes. They will increasingly support the ongoing digital revolution in our farms and businesses.
Figure: Examples of portable spectrometers tested at the CRA-W.