Empire and indigestion: Materializing tannins in the Indian tea industry

In the mid-1800s, plantation-produced tea from India came onto the British market. Tea retailers blended this more malty and black tea with the lighter Chinese-grown tea to which consumers had become accustomed. By the turn of the 20th century, blending helped Empire-grown tea supplant Chinese-grown tea on the market. Scholars of tea have shown how British tea companies working in South Asia stoked racialized fears that Chinese tea arrived in Britain in an adulterated state, laden with impurities that included dyes, perfumes and even human sweat. This article describes how concerns about protecting tea leaves from outside adulteration gave way to concerns about the potential digestive threat that lay inside tea leaves themselves. Medical journals linked the increased consumption of Indian teas to a population-wide 'epidemic' of indigestion. The most cited culprits in this epidemic were tannins, chemical compounds that were also thought to give black tea its characteristic bitterness and color. The normalization of black tea consumption among the British public was not just a work of marketing or branding but a work of resolving uncertainty about what tannins were at a material, biophysical level. As this uncertainty was resolved scientifically, tea was materialized not as a singular, unified product but as an active chemical assemblage.