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Tea/tea pasteurization


QUESTION: John, we are able to brew sweet tea at a top temperature of 252F for one hour. What do you think would be the stable shelf life stored at ambient temperature?

ANSWER: Hello, and thank you  for your question! When we brew tea, we remove natural oils from the leaves to flavor the water. This is why we don't usually reuse teabags. After a certain number of brews, there would be no flavor left to be steeped from the leaves. The same thing applies to tea storage. You can store tea for a pretty long time in a dry environment,  but you have to keep it in a sealed container to prevent the oils from evaporating. With bagged tea, that means leaving it in its packaging. With loose leaf, that usually means a tea tin. Even so, the flavor will begin to escape. Depending on the quality of the tea and the airtightness of the container, you've got anywhere from 6 six months to 3 years of storage before the flavor is gone. Consult the packaging or manufacturer for a more  exact date (but bear in mind that they tend to give early estimates so that customers will buy new tea!) The tea is probably safe to drink after that, but it won't have much flavor left. Additionally, proper storage relies on a dry environment. The leaves can't start to rot while they remain dry, but if they're kept in a humid environment for too long, they'll start to gain their moisture back, giving bacteria the opportunity to start breaking the leaves down. I hope this helps, and  don't hesitate to let me know if you have any other questions!

---------- FOLLOW-UP ----------

QUESTION: Read the question again, please. I asked about brewed tea.

Sorry for the confusion! After tea is brewed, the shelf life is dramatically shortened. While it is being brewed, the high temperature lowers the risk of bacterial infection. The CDC does not recommend brewing at room temperature as this provides an environment more conducive to bacterial growth. Contamination becomes possible once the tea is being held at room temperature with the risk increasing the longer it is held there. If the tea is refrigerated after brewing, it has a shelf life of about three days or up to five if the mixture hasn't started to cloud over. If it's being held at room temperature without refrigeration, I wouldn't give it more than eight hours before it starts to become unsafe for consumption.


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I can answer questions about the preparation of tea, the different kinds of tea and their properties, and many of the other questions I know you tea drinkers and would-be tea drinkers have.


Tea has become something of an obsession for me. I prepare loose-leaf as well as bagged tea, and am starting to explore the many different kinds.

Graduated high school with high honors

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