MadSci Network: Biochemistry |
Aloha, Violet, I'm not sure if egg yolks remove coffee stains or not. However, if they do, it would be most likely be due to the fat and fat-like compounds (especially lethicin, a phospholipid) in egg yolks that would dissolve the fat-soluble components (oils/fats) that make up the color of coffee. With regards to the tea stain/vinegar connection: The most probable answer would be that the colored phytochemical compounds (chemicals found in plants), such as polyphenols/tannins, that provide the color to tea are broken down by the vinegar (which is a weak acid) and become more soluble and can be washed away. These were my 'best guesses,' but I also checked with one of my food science/chemistry colleagues, Dr. Alvin Huang on the University of Hawai`i faculty, and he concurred with my answers. Since my training is in nutition sciences, it's always good to have someone confirm my answers to more food-related questions, especially when they are related to food chemistry.
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