Hot water in filter brewing

#1: Post by **mathof** » February 26th, 2016, 5:01 pm

I've just started filter brewing, with a Chemex. Before I was using French press. With French press, after the blooming phase, you just dump all the hot water in the glass receptacle and wait a few minutes. With French press, by contrast, you are adding small amounts of water for several minutes. My question is: do you put the kettle back on the hob to keep it boiling between pours, or do you just let it gradually cool down while you are waiting to pour more water into the paper cone?

Matt

#2: Post by **yakster** » February 26th, 2016, 5:03 pm

I overfill the kettle by 100 ml or more to help maintain the temps and do put it back on the HOB between pours to keep the temps up. I know that Todd Carmichael when he competed glued the base of his electric kettle on so that he could keep the water heated during the pour, but I think that might be going a bit far.

#3: Post by **treq10** » February 26th, 2016, 8:14 pm

Even though it may seem like you're brewing with different water temps, it's actually quite similar. After you pour in all the water into the french press, the temperature of the slurry will cool throughout the brew time. During a pour over, the same thing happens, perhaps at a slightly faster rate, but the finer grind size compensates for the difference. If you reheat the water in the kettle for the pour over, you'll extract faster than if you don't, although I'm not 100% confident about this. I'd say AB test and see what you find. Otherwise, most people who brew with a pour over system don't reheat the water so I wouldn't worry about it.

#4: Post by **happycat** » March 1st, 2016, 10:54 pm

yakster wrote:I overfill the kettle by 100 ml or more to help maintain the temps and do put it back on the HOB between pours to keep the temps up.

Me too. I roast light. Tastes great. I also vigorously bloom the coffee at start with a chopstick and maybe 2/3 water to gm of coffee then let bloom 30s. Seems to slow down the brew a lot... I use much coarser grinds with hot hot water.

#5: Post by **yakster** » March 1st, 2016, 11:26 pm

I think Happycat's on to something, keeping the water hot really helps with lighter roasts. I used to wait for the water to cool more but followed some pro Barista's advice to just use right off the boil water and it's been an improvement, at least for lighter roasts.