lignin is a complex organic polymer that gives vascular plants their fibrous, woody character. Lignin is a major component of wood (between 15 and 35 percent of the dry material), supplying the material for the rigid tubular systems (xylem and phloem) that are necessary for the distribution of water and nutrient fluids (sap) throughout the plant. When altered by heat or fire, lignins offer aromas of vanilla, eugenol (clove), and 4-methylguaiacol (or vanilla/spicy/smoky aromas). See aroma.
“Lignin.” American Chemical Society. https://www.acs.org/content/acs/en/molecule-of-the-week/archive/l/lignin.html (accessed February 9, 2021).
By: Doug Frost