LIBS in Manufacturing
Adulteration control, along with the authentication of manufactured goods and origin certification are all very complex processes. In some cases, fraud detection can be challenging due to the similar chemical composition of the used adulterants.
Tobacco is an agricultural product originating in America that is obtained by processing the leaves of various plants of the genus Nicotiana tabacum. It is the inedible product occupying the most plantings in the world, according to a recent report from the United Nations Food and Agriculture Organization. It is consumed in various ways, but the most popular form of consumption is, undoubtedly, by smoking cigarettes. A particular segment of the tobacco industry is the manufacturing of handmade cigars, which for some third-world countries is an important source of income. There are different qualities of cigars, and a major problem is the adulteration that occurs, for example, when authentic high-quality leaves are replaced by lower quality leaves. A factor that influences the quality of the cigars is the smoke combustion process, which depends on several factors, particularly the composition of the leaves. We present a simple and quick technique for the quality control and origin identification of handmade cigars that measures the Mg/Ca ratios in the tobacco leaves and wrappers of the cigars using laser-induced breakdown spectroscopy.
SEM image of the laser-treated surface, magnification x500.
(a) Outside parts of a cigar. (b) Dried bunches of leaves inside a cigar
SEM image of the non-treated surface, magnification x500.
Typical spectrum of tobacco. Inset: The Mg and Ca characteristic lines used for measurements.
Total Mg/Ca ratio intensity bar graphs, defined as (Mg/Ca)leaves þ (Mg/Ca)wrapper for the 10 brands of cigars. Bra, Basil; Mex, Mexico; Nic, Nicaragua; R Dom, Dominican Republic.