10 thoughts on “The Key To Coffee”

  1. Coffee inspires science! In more ways than one…

    I recently picked up a cheap barbecue thermometer with a prong thin enough to fit through the whistle hole on my kettle, and finally quantified the brew-temp-versus flavor matter.

    I was surprised – peak flavor happens a lot lower than I’d thought, down around 165-170F. (Lower than that and the coffee is lukewarm – even there, the cup needs preheating.) Which explains why getting the really rich almost chocolatey (tastes-almost-like-it-smells!) flavor was such a hit-or-miss thing – before I ran instrumented tests, I’d only brew that far below boiling by accident.

    I’m not shocked that water mineral content affects coffee flavor. I eliminated that factor a long time ago when I started using reverse osmosis filtered water for all cooking, due to a bout with kidney stones. (OW) Turns out water in the southwest tends to have a LOT of dissolved calcium in it. (Going to RO water worked, no repeats in twenty years, knock wood.)

    Meanwhile, an eight-buck Walmart barbecue thermometer is probably an easier coffee upgrade than tinkering with the water chemistry.

    1. What brewing method are you using?

      For coarse grounds in an insulated French press I’ve found that 185-190F works best, and filtered water is a requisite.

      1. I use an Aeropress. Gets the full immersion of a french press with the quick flavor extraction of an espresso and the convenience of a drip coffee maker. I use an electric kettle which auto shuts off at 212F and then let it sit for a minute which brings it down below 205F. Then, when I pour into the Aeropress it quickly drops down to approx. 185F. I pour just one or two ounces on the beans first to produce a frothy “bloom” an let it sit for 10 seconds. Then, I pour water up to the top of the brew chamber which about 5 ounces and then stir for about 3 seconds. Put the plunger on and let it sit for 10 seconds and then start pressing slowly till about T+30 seconds. With that you end up with nearly espresso strength coffee but I pour in another 5 ounces of water for an americano. I can’t recommend the Aeropress enough. You get a very clean cup of coffee that is low in acidity but still has full flavor and body. Plus, it is much easier to cleanup than a french press and you don’t get a layer of sludge in the bottom of the cup.

    2. I have found that is similar with tea. Too hot and tea can turn bitter. Currently using water around 180-185 and the flavor is much better than with water at a full boil. Currently on an Earl Grey Green tea kick and this flavor is pretty good and quite affordable, http://www.amazon.com/Bigelow-Green-Tea-20-Count-Boxes/dp/B000GFYRHQ

      Can usually stretch out one tea bag into 3 or 4 12oz cups of tea.

      I filter the water through a brita but it is still really hard. Will have to play around and see if different types of water make a difference in flavor. Hard water is a pain. Both the keurig and cuisinart tea pot get descaled monthly.

      1. A Britta filter is basically an activated carbon (AC) filter. AC is pretty ineffective at filtering out metal ions, e.g. sodium, magnesium, calcium. AC does well against organic molecules like benzene,

  2. The same is true for making doughs. A while back there were articles about why the same recipe for pizza dough didn’t taste the same when not cooked in NYC and they determined it was water. One pizza maker even went so far as to import water from NYC. But Gothamist thinks this is a myth and relates the findings of a taste test which shows there was no difference from the water but the crispness of the crust determined what tasted best. http://gothamist.com/2010/01/08/the_water_makes_the_pizza.php

  4. Bourbon and Tennessee whiskey are produced almost entirely in Kentucky and Tennessee because the local water is free of iron, and the whiskey made from it is superior to that made elsewhere (an observation made years before anyone knew about dissolved iron). The first time I went to Europe, in 1969, I found that Coca Cola didn’t taste the same as it did in the U.S., and didn’t taste the same from one country to the next. It was all due to differences in the water.

    Municipal water treatment has become ubiquitous and somewhat standardized, so regional variations have diminished greatly – but they still exist. Given what we now know about water (how to manipulate its purity to the ppb range with relative ease) it would seem that a small processing device could be installed in every coffee shop to do a finish optimization on the local feedstock.

  5. I’ve found that coffee tastes best when brewed from the gallon jugs of filtered ‘drinking water’ from the store. The water suppliers filter the water down to 0 PPM with reverse osmosis. Then they add back a proprietary mixture of calcium carbonate, magnesium carbonate, and sodium/potassium salts to reproduce the taste of “fresh water”. On some cheap store brand water I’ve seen the only ingredient is just calcium carbonate. And indeed, if you roll this water around in your mouth and swallow it just tastes like a piece of chalk (yes, I’ve licked chalk….). When you spend more on water you’re really just paying for a more diverse blend of minerals.

    Still though, just removing the stuff that causes funny tasting water will certainly improve the flavor of brewed coffee or tea.The Brita filter removes the aromatic compounds that cause the off putting smells and tastes but doesn’t do much to the overall mineral content. I’ve tested water filtered through a Brita with a dissolved solids water tester and it has pretty much the same PPM as if it came right straight out of the tap. Tap water is about 160 PPM in my area and after being filtered through a Brita is about 145. My county water report shows the majority of the water has dissolved solids of calcium and magnesium with organic compounds in the ten’s of PPM.

Comments are closed.