2. The main industrial extraction techniques for natural tannins

2.1 Tannin extraction in history

Tanning skins to make them rot-proof was invented at the very beginning of human activity. The first observations date back to the Upper Paleolithic, with the arrival of Homo Sapiens 45,000 years ago . The first leathers were made by immersing hides in water in which tree bark or tannin-rich wood had been left. This artisanal method took up to a full year to produce good leather. However, it wasn't until the 19th century that the tannin extraction industry was established. The industrial adventure began in Lyon, France and northern...