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- Complaint Case Studies Coloration of Black Tea
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Complaint Case Studies Coloration of Black Tea
Last updated on March 3, 2025.
1.Overview
After drinking a soft drink (tea), two people vomited in 15-20 minutes.
Black tea (left: Complaint right: Target product)
2.Results of the survey
- Appearance: It was black-brown and found sediment.
- ｐH： 3.7 (Contrast 3.9)
3.Conclusion
The tannin contained in the ingredients in the tea became iron tanninic acid and turned black.
4.Reference
Tannin: A generic term for aromatic compounds with complex structures with a large number of phenolic hydroxy groups. It binds with iron (3.) ions to form dark green or purple complex compounds. It is widely distributed in the plant world.
Published on March 8, 2007
Inquiries to this page
RIKEN, Medical Care Bureau Institute of Hygiene
Phone: 045-370-9451
Phone: 045-370-9451
Fax: 045-370-8462
E-Mail address [email protected]
Page ID: 978-043-407
