Near Infrared Spectroscopy, A New Tool to Characterize Wood for Use by the Cooperage Industry

Auteur(s)

Gilles Chaix,^1,2,3 Thomas Giordanengo,⁴ Vincent Segura,⁵ Nicolas Mourey,⁴ Bertrand Charrier⁶, Jean Paul Charpentier,⁵

Résumé

It is important for the industry to be able to quickly measure and/or evaluate the mechanical, physical and chemical properties of wood. Whether it is upstream in the field, on a living tree, when transformed into timber or in industrial product, during and after the material is put into operation. Among the non-destructive measurement techniques that have been developed since the 1980s, spectroscopy based on emission or absorption in the near infrared (NIR spectroscopy), i.e., in the frequencies between 800 and 2500 nm, offers a new field of possibilities for analysis and evaluation of the quality of materials. While NIR spectroscopy is still not widely used in the wood industry, it is more developed in other industrial sectors such as petrochemicals, pharmaceuticals, agriculture, agrotechnology, food and textiles.
Since the early 1990s, numerous research studies have explored the value of using NIR spectroscopy to estimate the properties of wood material. This represents more than 500 scientific articles published in this sector with an average since the end of the 2000s of about 40 articles published each year (Tsuchikawa 2007, Tsuchikawa and Kobori 2015). This chapter attempts to take stock of the theoretical and practical aspects of SPIR technology and highlights through multiple examples, the wide potential of this measurement tool in the field of wood quality assessment and in the use and processing of wood material.
In the first part, is discussed the general elements of the NIR spectroscopy methodology and present the significant results of the scientific literature. In the second part, we report the first industrial application of NIR spectroscopy in the field of the chemical quality of oak wood for cooperage. We do not seek to be exhaustive but rather to describe some of the most iconic applications, and to make the reader want to go further, such as the examples of durability conferred and cooperage. For an exhaustive view, we recommend reading bibliographic reviews (Tsuchikawa 2007, Tsuchikawa and Schwanninger 2013, Tsuchikawa and Kobori 2015) and specialized works (Osborne et al. 1993, Bertrand and Dufour 2006).