This article is an extension of a previous topic Tea Aroma. I talked about types of aroma and where they come from and how some are produced.
True aroma is one of the natural essences of the plant, nothing different than the smell from a rose. Added scent on the other hand isn't naturally an essence of the tea itself. Popular Jasmine tea is traditionally scented with natural flowers, nowadays some producers add scented oil to simulate the aroma. Although both are not naturally part of the tea, the former is some what more natural then the later. How can one identify the difference? Aside of experienced nose to detect the chemical content of the scented oil, a simple step can help you separate the two.
Use separate cups for each tea, add hot boiling water to each cup, then place a thin scent free tissue over each cup covering the top for 5 minutes. If you can smell a scent on the tissue after it's dried, the tea in the respective cup is scented with oil.
This method is primarily to determine the authenticity of tea aroma, however does not apply to blended tea or teas that are flavored as part of a recipe.