Comments on: Brew temperature http://www.jimseven.com/2009/10/27/brew-temperature/ James Hoffmann's coffee blog. Tue, 16 Mar 2010 23:37:25 +0000 hourly 1 By: Chris Ilias http://www.jimseven.com/2009/10/27/brew-temperature/#comment-98432 Chris Ilias Thu, 25 Feb 2010 21:15:24 +0000 http://www.jimseven.com/?p=1161#comment-98432 I've been thinking about this for tea for some time, and of course, it's equally valid for coffee. I started brewing tea at home inside a <a href="http://www.flickr.com/photos/ilias/4388347248/" rel="nofollow">simmering pan of water</a>. I figure it's about as controlled as I can get with the simplest of hardware. I’ve been thinking about this for tea for some time, and of course, it’s equally valid for coffee. I started brewing tea at home inside a simmering pan of water. I figure it’s about as controlled as I can get with the simplest of hardware.

]]> By: Tom Jagiello http://www.jimseven.com/2009/10/27/brew-temperature/#comment-97655 Tom Jagiello Sat, 28 Nov 2009 11:15:59 +0000 http://www.jimseven.com/?p=1161#comment-97655 just got my datalogger and made a few tests with it. It all really depends how you brew your coffee, is it with a boiler that can supply water at a steady temperature throughout the whole process, with slow flow and good dispersion, or is it using a kettle and pouring from it manually? I normally use an ordinary kettle to boil the water (not PIDed yet), transfer that to a metal jug, let it cool to around 92*C and pour. Today I measured the temperature under the coffee bed and it's 85*C at the beginning and 82*C at the end, the coffee itself was 72*C. I know that it's only one test, but I was curious if anyone did anything similar and what differences did he/she find. Regards, dsc. just got my datalogger and made a few tests with it. It all really depends how you brew your coffee, is it with a boiler that can supply water at a steady temperature throughout the whole process, with slow flow and good dispersion, or is it using a kettle and pouring from it manually? I normally use an ordinary kettle to boil the water (not PIDed yet), transfer that to a metal jug, let it cool to around 92*C and pour. Today I measured the temperature under the coffee bed and it’s 85*C at the beginning and 82*C at the end, the coffee itself was 72*C. I know that it’s only one test, but I was curious if anyone did anything similar and what differences did he/she find.

Regards,
dsc.

]]> By: Rasmus Helgebostad http://www.jimseven.com/2009/10/27/brew-temperature/#comment-97595 Rasmus Helgebostad Wed, 18 Nov 2009 15:20:08 +0000 http://www.jimseven.com/?p=1161#comment-97595 James, just a quick note on the vessel: I usually preheat the brewing wessel with boiling water, then measure the temperature of that water before tossing it out. This to try to be as consistent as possible with vessel temperature before brewing. For french press I use a pre-heat temp of 80 degrees celsius, more because it's easy replicable than anything else. Thoughts? James, just a quick note on the vessel: I usually preheat the brewing wessel with boiling water, then measure the temperature of that water before tossing it out. This to try to be as consistent as possible with vessel temperature before brewing. For french press I use a pre-heat temp of 80 degrees celsius, more because it’s easy replicable than anything else. Thoughts?

]]> By: jeff verellen http://www.jimseven.com/2009/10/27/brew-temperature/#comment-97546 jeff verellen Fri, 06 Nov 2009 12:43:58 +0000 http://www.jimseven.com/?p=1161#comment-97546 Erik, thank you for referring to that author. I have looked into him, and will read his work. Brewing longer at lower temperatures definitely changes the taste, but the amount of flavor seems comparable to classic methods. I think that some flavors can only be extracted if the brew is exposed to higher temperatures, but also, I think that deeper, earthier flavors can only come to their right if extracted at lower temperatures and longer times. The heat could have an adverse effect to that range of flavors. Erik, thank you for referring to that author. I have looked into him, and will read his work. Brewing longer at lower temperatures definitely changes the taste, but the amount of flavor seems comparable to classic methods. I think that some flavors can only be extracted if the brew is exposed to higher temperatures, but also, I think that deeper, earthier flavors can only come to their right if extracted at lower temperatures and longer times. The heat could have an adverse effect to that range of flavors.

]]> By: AndrewF http://www.jimseven.com/2009/10/27/brew-temperature/#comment-97545 AndrewF Fri, 06 Nov 2009 04:39:14 +0000 http://www.jimseven.com/?p=1161#comment-97545 I've often wondered if the people who say they prefer to french press their coffees, as opposed to brewing them in a vacpot, prefer it because of the lower temp the french press tends to brew at. If I start with a room temp french press (10 oz, glass) it brews around 185 F. I tried to see what the lowest I could get my vacpot to so I could compare the cups together, and could only get it to 192 F. I still want to try some other things to lower this temperture but this is certainly something to think about. I’ve often wondered if the people who say they prefer to french press their coffees, as opposed to brewing them in a vacpot, prefer it because of the lower temp the french press tends to brew at. If I start with a room temp french press (10 oz, glass) it brews around 185 F. I tried to see what the lowest I could get my vacpot to so I could compare the cups together, and could only get it to 192 F. I still want to try some other things to lower this temperture but this is certainly something to think about.

]]> By: Erik Fooladi http://www.jimseven.com/2009/10/27/brew-temperature/#comment-97542 Erik Fooladi Thu, 05 Nov 2009 22:10:37 +0000 http://www.jimseven.com/?p=1161#comment-97542 Jeff: time and temperature are linked in a complicated way, and would be differently so for different substances. Hence, the <i>change</i> in rates of extraction for various compounds with temperature will not be the same. Consequence: coffee extracted at low temperature for longer time will inevitably have a different flavour than coffee extracted for a shorter time at a higher temperature. A simple model experiment is to make tea and compare degree of astringency and bitterness. Steep the leaves in water at ambient temperature for as long as you like and see if you can make a tea that tastes as astringent and/or bitter as one that is overextracted for just a few minutes at high temperature. For scientific studies on coffee extraction, look for references to Michael Spiro which has published loads on the topic for more than two decades. Jeff: time and temperature are linked in a complicated way, and would be differently so for different substances. Hence, the change in rates of extraction for various compounds with temperature will not be the same.

Consequence: coffee extracted at low temperature for longer time will inevitably have a different flavour than coffee extracted for a shorter time at a higher temperature.

A simple model experiment is to make tea and compare degree of astringency and bitterness. Steep the leaves in water at ambient temperature for as long as you like and see if you can make a tea that tastes as astringent and/or bitter as one that is overextracted for just a few minutes at high temperature.

For scientific studies on coffee extraction, look for references to Michael Spiro which has published loads on the topic for more than two decades.

]]> By: Jeremy http://www.jimseven.com/2009/10/27/brew-temperature/#comment-97538 Jeremy Wed, 04 Nov 2009 05:16:08 +0000 http://www.jimseven.com/?p=1161#comment-97538 Great. Now I won't sleep tonight. Great. Now I won’t sleep tonight.

]]> By: jeff verellen http://www.jimseven.com/2009/10/27/brew-temperature/#comment-97530 jeff verellen Sat, 31 Oct 2009 14:10:01 +0000 http://www.jimseven.com/?p=1161#comment-97530 you are saying that output temperature from lets say a boiling water from a kettle to pouring that water on the ground coffee resulting in the brewing muck should be researched and clarified. This implies knowing the humidity, ambient temperature and temperature of the brewing device itself. you are saying that output temperature from lets say a boiling water from a kettle to pouring that water on the ground coffee resulting in the brewing muck should be researched and clarified. This implies knowing the humidity, ambient temperature and temperature of the brewing device itself.

]]> By: Cecil http://www.jimseven.com/2009/10/27/brew-temperature/#comment-97528 Cecil Sat, 31 Oct 2009 03:43:32 +0000 http://www.jimseven.com/?p=1161#comment-97528 That different coffees will react well to some temps more than others is something we are used to. But there is a need to describe brew temps better than by the output temp, maybe a average temp at the start of brewing in the brew vessel. This would be less useful in espresso but more so in press or other types of brewing. -C That different coffees will react well to some temps more than others is something we are used to. But there is a need to describe brew temps better than by the output temp, maybe a average temp at the start of brewing in the brew vessel. This would be less useful in espresso but more so in press or other types of brewing.

-C

]]> By: jeff verellen http://www.jimseven.com/2009/10/27/brew-temperature/#comment-97521 jeff verellen Thu, 29 Oct 2009 09:20:38 +0000 http://www.jimseven.com/?p=1161#comment-97521 I must correct myself, this CAN imply a smooth curve of brewing. But, depending on the type of graph you are using and the markings, it can have a steep slope. I must correct myself, this CAN imply a smooth curve of brewing. But, depending on the type of graph you are using and the markings, it can have a steep slope.

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