What Makes Scum on Teacups?

Written by sachiko schott
  • Share
  • Tweet
  • Share
  • Pin
  • Email
What Makes Scum on Teacups?
The scum of black tea is caused by molecules left behind. (black tea image by Horticulture from Fotolia.com)

Black teas can leave a scum on the inside of teapots and teacups that is difficult to remove using normal dish detergents. This stain is caused by pigments left behind when the water in the tea evaporates.

Pigments in Tea

Black tea contains pigments that are formed during the fermentation of the tea leaves. Part of the scum left in teacups is made up of these pigments, which are partly absorbed into the porcelain of the cup.

Tea Scum and Oxidation

Tea scum is also composed of organic and inorganic compounds that undergo oxidation reactions that stabilise them onto the teacup. Oxidation reactions occur between oxygen and other molecules, and in this case occur when the compounds in the tea are exposed to air as the water in the tea evaporates.

Removing Tea Scum

The tea scum that forms inside teapots and teacups is difficult to remove. But a good scrubbing with a damp rag and some baking soda usually works.

Don't Miss

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the eHow.co.uk site, you consent to the use of cookies. For more information, please see our Cookie policy.