|MadSci Network: Chemistry|
I'll have to admit that, as a nutrition scientist, I wasn't quite sure of the answer to your question. My first guess was carmel flavoring (burnt sugar flavor). However, I have a dear colleague, Dr. Alvin Huang, who is a food scientist, and upon whom I rely for information in just such cases. Dr. Huang had a number of years working for the food industry, although he and I have both been university faculty members here together at UHManoa for about 10 years.
Alvin got back to my voice-mail message to him, this morning. The major 'natural flavor' agent in cola-type drinks (such as Coke and Pepsi) is actually caffeine. Alvin said it is the caffeine that is obtained from the process of decaffeinating coffee beans, and the food industry doesn't want to waste it, I guess. Caffeine imparts a 'bitey' or astringent taste to the drink. Also, sugar is actually a 'natural flavor,' but it is listed, sometimes, directly as an ingredient.
I hope this answers your question. I really enjoy this type of question, because it makes me do some 'digging' for the answer, myself... good practice for me.
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