Comments on: The Laser Thermometer http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html In LA, but Still Exploring Desserts Tue, 06 Jan 2009 02:52:17 +0000 http://wordpress.org/?v=2.6 By: I Love Stirring Caramel {blush} - Sweet Napa http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html#comment-21026 I Love Stirring Caramel {blush} - Sweet Napa Thu, 07 Feb 2008 05:24:26 +0000 http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html#comment-21026 [...] So, I continue to stir and add sugar until all my sugar is in the pot. This is when doneness counts. At this point, there is already so much heat under the pot and in the pot — sugar caramelizes at about 310F (as a comparison, bread is done at an internal temp of only 195F) — that I turn the heat down to medium so that the remaining crystals melt and caramelize without burning the sugar that has already caramelized. The sugar is already quite brown and caramel-y at this point, so I only vaguely go by a nice rich caramel color. I think that the most important thing is that all the sugar crystals are melted. It’s slightly tricky because the caramel naturally has air bubbles in it, which also look like crystals, so I look closely at it. I then stir gently, b/c stirring vigorously wouldn’t accomplish anything except letting heat escape. When there are no more visible crystals and it’s a lovely deep caramel color, I stop cooking it by adding fats on low heat. If there are still sugar crystals, they can lead to graininess or clump into hard bits. I’ve found that my laser thermometer can pick up the temp of caramel just fine; mine usually gets to around 340F. If you think it’s close to being done but are scared of burning it, you can take it off the heat and it will finish due to the residual heat. Unless you go all Michael Recchuiti, burnt sugar isn’t good for much. I think it’s better to go slower at the end than to risk wasting the whole batch. Candy thermometers are not so useful here because you’ve lost so much moisture while caramelizing that the caramel usually isn’t deep enough to get a good reading. And if you were to add fats to it, there’s a chance that the sugar on the thermometer wouldn’t dissolve completely when added. Also, if you have a lot of caramelized sugar, chances are you’re adding a lot of fat that will bubble up, so you want the caramel to be as shallow as possible so that it won’t bubble out of the pot. A candy thermometer should be added only after you’ve added any additional wet ingredients and have stirred to incorporate. [...] [...] So, I continue to stir and add sugar until all my sugar is in the pot. This is when doneness counts. At this point, there is already so much heat under the pot and in the pot — sugar caramelizes at about 310F (as a comparison, bread is done at an internal temp of only 195F) — that I turn the heat down to medium so that the remaining crystals melt and caramelize without burning the sugar that has already caramelized. The sugar is already quite brown and caramel-y at this point, so I only vaguely go by a nice rich caramel color. I think that the most important thing is that all the sugar crystals are melted. It’s slightly tricky because the caramel naturally has air bubbles in it, which also look like crystals, so I look closely at it. I then stir gently, b/c stirring vigorously wouldn’t accomplish anything except letting heat escape. When there are no more visible crystals and it’s a lovely deep caramel color, I stop cooking it by adding fats on low heat. If there are still sugar crystals, they can lead to graininess or clump into hard bits. I’ve found that my laser thermometer can pick up the temp of caramel just fine; mine usually gets to around 340F. If you think it’s close to being done but are scared of burning it, you can take it off the heat and it will finish due to the residual heat. Unless you go all Michael Recchuiti, burnt sugar isn’t good for much. I think it’s better to go slower at the end than to risk wasting the whole batch. Candy thermometers are not so useful here because you’ve lost so much moisture while caramelizing that the caramel usually isn’t deep enough to get a good reading. And if you were to add fats to it, there’s a chance that the sugar on the thermometer wouldn’t dissolve completely when added. Also, if you have a lot of caramelized sugar, chances are you’re adding a lot of fat that will bubble up, so you want the caramel to be as shallow as possible so that it won’t bubble out of the pot. A candy thermometer should be added only after you’ve added any additional wet ingredients and have stirred to incorporate. [...]

]]> By: Nina http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html#comment-520 Nina Mon, 22 May 2006 05:20:46 +0000 http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html#comment-520 fattypr - You just have to figure out how to justify using one of these in your lab.... :) From Our Kitchen - I think it's great for tempering chocolate, and will probably save me money and time with wasted chocolate. :) But I've realized that for creme anglaise -- and probably other egg-based sauces -- it just can't produce a perfect reading for the whole pot -- but I don't think that other thermometers really can, either; I'll have to eyeball it. I also like it for glazes that need to be heated to a certain temp, and for stove top temperatures. I'm still playing around with it, so I'll probably write a post in a while that's more comprehensive about uses that I've found for it. Paul - I'm glad you like my site. :) And you're right. Technically, this uses "infrared technology" to measure the temperature, while the red laser sight dot is just used for aim -- it can even be turned off to save the battery. The company probably just emphasizes the laser because it sounds cool. As far as distance goes, it has a Distance to Spot Ratio of 8:1, so the field of view does get larger the farther away you are from it. I did some tests to measure a spot on a wall from about 30 ft away and then from up close, and the difference was about .5-1.5 degrees, with the temp taken from farther away always being lower. So yeah, I'll usually be standing right at the pot that I'm measuring, though I can give a rough idea of a temperature to someone further away. Gerald - I got mine at this site for $74.95 with free shipping. http://www.kitchen-universe.com/detail.aspx?s=shopping&ID=1260 fattypr - You just have to figure out how to justify using one of these in your lab…. :)

From Our Kitchen - I think it’s great for tempering chocolate, and will probably save me money and time with wasted chocolate. :) But I’ve realized that for creme anglaise — and probably other egg-based sauces — it just can’t produce a perfect reading for the whole pot — but I don’t think that other thermometers really can, either; I’ll have to eyeball it.

I also like it for glazes that need to be heated to a certain temp, and for stove top temperatures. I’m still playing around with it, so I’ll probably write a post in a while that’s more comprehensive about uses that I’ve found for it.

Paul - I’m glad you like my site. :) And you’re right. Technically, this uses “infrared technology” to measure the temperature, while the red laser sight dot is just used for aim — it can even be turned off to save the battery. The company probably just emphasizes the laser because it sounds cool. As far as distance goes, it has a Distance to Spot Ratio of 8:1, so the field of view does get larger the farther away you are from it. I did some tests to measure a spot on a wall from about 30 ft away and then from up close, and the difference was about .5-1.5 degrees, with the temp taken from farther away always being lower. So yeah, I’ll usually be standing right at the pot that I’m measuring, though I can give a rough idea of a temperature to someone further away.

Gerald - I got mine at this site for $74.95 with free shipping. http://www.kitchen-universe.com/detail.aspx?s=shopping&ID=1260

]]> By: Gerald http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html#comment-486 Gerald Thu, 18 May 2006 18:57:05 +0000 http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html#comment-486 I've been thinking about getting one of those, how much was it? I’ve been thinking about getting one of those, how much was it?

]]> By: Paul Dulaney http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html#comment-485 Paul Dulaney Wed, 17 May 2006 20:52:07 +0000 http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html#comment-485 Great website! As an engineer I would just say that this device is almost certainly not measuring the temperature with the laser; the laser just acts as a sight. It uses some kind of infrared receiver to measure the temperature whose beamwidth is much larger than that the laser. What that means practically is that you should hold the device as close as is comfortable to the object being measured -- it's accuracy across the room, say, is probably terrible. Great website!

As an engineer I would just say that this device is almost certainly not measuring the temperature with the laser; the laser just acts as a sight. It uses some kind of infrared receiver to measure the temperature whose beamwidth is much larger than that the laser. What that means practically is that you should hold the device as close as is comfortable to the object being measured — it’s accuracy across the room, say, is probably terrible.

]]> By: From Our Kitchen http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html#comment-483 From Our Kitchen Wed, 17 May 2006 03:06:47 +0000 http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html#comment-483 I've always wanted one of those! Does it live up to the price? I’ve always wanted one of those! Does it live up to the price?

]]> By: fattypr http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html#comment-482 fattypr Wed, 17 May 2006 01:59:56 +0000 http://www.sweetnapa.com/2006/05/15/the-laser-thermometer.html#comment-482 hahahaha!!!! i love it. hahahaha!!!! i love it.

]]>