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Name: Ruth
Status: student
Grade: other
Location: Outside U.S.
Country: USA
Date: Spring 2013

Why must trypic soy agar cooled below 50 C before poring and inoculation?

Agar doesn't have to be cooled to 50 C before pouring a plate; it can be poured at any reasonable temperature that won't be dangerous to handle. The reason people frequently wait to pour the agar until it is cooler is because it will solidify quickly in the plate. This keeps excessive moisture from condensing on the underside of the plate cover.

S. Unterman Ph.D.

Hi Ruth,

Thanks for the question. I would think that the agar needs to be cooled below 50 degrees C so that it can begin to precipitate and begin form a uniform gel.

I hope this helps. Please let me know if you have more questions. Thanks Jeff

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