# Is there a way to proof yeast without a thermometer?

**URL:** https://boards.straightdope.com/t/is-there-a-way-to-proof-yeast-without-a-thermometer/232998
**Category:** Factual Questions
**Created:** [March 7, 2004, 7:31pm UTC](https://boards.straightdope.com/t/is-there-a-way-to-proof-yeast-without-a-thermometer/232998 "2004-03-07T19:31:56Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![criminalcatalog](https://avatars.discourse-cdn.com/v4/letter/c/e68b1a/32.png) [@criminalcatalog](https://boards.straightdope.com/u/criminalcatalog)
#### Post date: [March 7, 2004, 7:31pm UTC](https://boards.straightdope.com/t/is-there-a-way-to-proof-yeast-without-a-thermometer/232998/1 "2004-03-07T19:31:56Z")

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Is there a way that I can MacGyver my way through a yeast proofing? I’m supposed to get this water inside a 5-minute window temperature (115d - 120d), and I have no thermometers. How can I find the temperature of this yeast without one?

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### Author: ![quiltguy154](https://avatars.discourse-cdn.com/v4/letter/q/ad7895/32.png) [@quiltguy154](https://boards.straightdope.com/u/quiltguy154)
#### Post date: [March 7, 2004, 8:22pm UTC](https://boards.straightdope.com/t/is-there-a-way-to-proof-yeast-without-a-thermometer/232998/2 "2004-03-07T20:22:28Z")

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You can use the ol’ reliable baby bottle test. Drip a few drops of the warm water to be tested onto the spot on your wrist where you can feel your pulse. If it feels neither cold, nor uncomfortably hot, then you can use the water to proof yeast. Even if the water IS too cool, the yeast will eventually proof. If it is too hot, you’ll kill the yeast and no evidence[bubbling, rising level within the proofing container, etc] will be in evidence. A pinch of sugar added to the water with the yeast will hurry things along. OR, you can use the fresh, compressed yeast that is sold in small, foil wrapped cubes in the dairy sections of supermarkets.

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### Author: ![criminalcatalog](https://avatars.discourse-cdn.com/v4/letter/c/e68b1a/32.png) [@criminalcatalog](https://boards.straightdope.com/u/criminalcatalog)
#### Post date: [March 7, 2004, 8:34pm UTC](https://boards.straightdope.com/t/is-there-a-way-to-proof-yeast-without-a-thermometer/232998/3 "2004-03-07T20:34:18Z")

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thank you, **quiltguy154**

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### Author: ![Chefguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chefguy/32/138_2.png) [@Chefguy](https://boards.straightdope.com/u/Chefguy)
#### Post date: [March 7, 2004, 11:37pm UTC](https://boards.straightdope.com/t/is-there-a-way-to-proof-yeast-without-a-thermometer/232998/4 "2004-03-07T23:37:14Z")

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Like he said. After dissolving the yeast, stir in some sugar. The yeast mixture should start to foam within a few minutes. No foam=dead yeast.