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Analysis of extracted coffee by gas chromatography
May 30, 2014 12:48 PM   Subscribe

Schrödinger’s water for the perfect cup of coffee
posted by pjern (26 comments total) 17 users marked this as a favorite

 
This is the alternate timeline where Walter White and Gale Boetticher decided to skip the whole meth thing and instead open up a coffee shop, isn't it.
posted by Drastic at 12:52 PM on May 30 [11 favorites]


Why do I find the name "Maxwell" so a propos for a coffee study?
posted by notsnot at 12:56 PM on May 30 [1 favorite]


I'd like to taste-test this theory. Can the ionic content of the water really make that much of a difference?
posted by Kevin Street at 1:09 PM on May 30


While it's still fetishizing food, I disagree with this:
However, it’s almost impossible for him to control the chemical composition of the incident water.
I'm pretty sure almost all college chem labs can do this easily and readilly.
posted by k5.user at 1:10 PM on May 30 [1 favorite]


It's physically possible to control the chemical composition, but it's almost impossible for the coffee shop guy to do it, since he doesn't have the equipment or expertise.
posted by Kevin Street at 1:13 PM on May 30 [2 favorites]


Overthinking a plate of coffee beans?

Just kidding... I enjoy this kind of stuff. Fascinating.
Also this why we need food replicators already!
posted by Hairy Lobster at 1:14 PM on May 30 [1 favorite]


I'm pretty sure almost all college chem labs can do this easily and readilly.

Right, but a coffee shop isn't a college chem lab. I mean, that's the point of the article: The chemist who wrote the article prepared water for the coffee guy, who used it to brew coffee and (apparently) got good results.
posted by my favorite orange at 1:20 PM on May 30


You would be surprised at how much the ionic content of water can affect flavor.

I'm a distiller now (former coffee guy), and it is mindblowing to taste our gin made with de-ionized water vs ionized water. The ionized water is significantly creamer, more rich of a mouthfeel... but we have to use D-I water because ionized water will form salts in the bottles. Like, little dandruff looking floaters in the bottles that form post-bottling, as a result of slow reactions taking place with the ionized water.

We switched to de-ionized water, and the salts went away, but the taste also significantly changed.

We recently made a 130 gallon batch that we (post-distillation) colored with red cinchona, in one of our yearly experimental gin batches. When we proofed down the cinchona infused gin with D-I water it turned brown. But when we proofed it down with non D-I water it stayed gloriously pink. And amazingly, now the salts didn't form.

Chemistry is weird. And terroir is real, and in the distilling world a lot of the terroir is the water. There's a reason why bourbons from different distilleries in a similar region can be so different. A lot has to do with aging conditions, obviously, but water is huge.
posted by special agent conrad uno at 1:20 PM on May 30 [21 favorites]


Today I learned the word terroir and I intend to use the shit out of it henceforth.
posted by rabbitrabbit at 1:26 PM on May 30 [7 favorites]


Ionic composition has a huge effect on organics extraction in water. It's not as simple as just pH effects or even dipole moments (the first moment), though those are important too, but you can talk about hard and soft ions (how polarizable the ions are, the second moment). Hyperpolarizability, the rate at which ions can polarize, the third moment, can be import too.

Salting-in (salts/ions making the organic more soluble) and salting-out (salts/ions making the organics less soluble) effects have large roles to play in taste profiles.

I suspect this is possible as just a few years ago there was some buzz that coffee had been "solved" chromatographically. That is essentially all of the flavour and odor compounds in coffee could be analyzed by gas or liquid chromatography (I can find a few articles on this, but they're paywalled, sorry. Here's an example.). So, that chemistry gives a baseline analytical toolbox for this kind of experimentation. It's only been possible at this level for the past 8 years or so.
posted by bonehead at 1:35 PM on May 30 [2 favorites]


I think beer brewers have this experience as well, that water source makes a tremendous difference in the product.
posted by Mei's lost sandal at 1:38 PM on May 30


That was an interesting read. I just ordered an Aeropress after years of settling for bad coffee at home, and I'm excited to start using it. I've heard that getting the water just right is sort of a big deal though...
posted by codacorolla at 1:41 PM on May 30


Awesome. Anyone with an ACS membership want to download the paper and tell us what the "best" cation blend is?

And while it may not be feasible to apply water treatments in a coffee shop, you could absolutely do it at home. A Brita filter is actually pretty good at eliminating most ions, though you could also get an RO filter if you really cared. And then you can get mineral water treatments at any homebrew store, or online.
posted by Joey Buttafoucault at 1:47 PM on May 30


Joey Buttafoucault: Awesome. Anyone with an ACS membership want to download the paper and tell us what the "best" cation blend is?

From the paper: "It should be noted that there is not one particular composition of water that produces consistently flavorsome extractions from all roasted coffee. Rather, there is water that has the most extracting ability (i.e., cation-rich), and the resultant flavor depends on the balance between both the cations in solution and the quantity of bicarbonate present (acting as a buffer). Furthermore, each bean is roasted to taste optimal when brewed with the water it was roasted to"
posted by James Scott-Brown at 1:52 PM on May 30


We recently made a 130 gallon batch that we (post-distillation) colored with red cinchona, in one of our yearly experimental gin batches. When we proofed down the cinchona infused gin with D-I water it turned brown. But when we proofed it down with non D-I water it stayed gloriously pink. And amazingly, now the salts didn't form.

I think this implies that red cinchona is a chelating agent, and that its red color depends on having a metal ion in its chelating center: deionized water pulls some of the metal out of the cinchona chelating center, causing it to turn brown; the non-DI water adds that metal back, re-reddening it, but then the metal is unavailable for combining with whatever was precipitating out as white flakes.
posted by jamjam at 1:54 PM on May 30 [7 favorites]


I used to make Aeropress right off the boil, but now stick to 170f. Much better.

Just learned about bulletproof coffee and this whole issue with molds and toxins including aflatoxin as found in moldy peanuts. What say you metafilter? Time to RTFA
posted by aydeejones at 2:03 PM on May 30


Can the ionic content of the water really make that much of a difference?

I can easily see that happening. The ionic content of water makes a huge difference in brewing beer, which is why brewing good copies of Pils and Burton Ales is basically impossible unless you either live in Pilsen* or Burton on Trent, or you modify your water to match the water in Pilsen/Burton.

Indeed, one term for adding substances to change the ionic profile of water in brewing is "Burtonization." Pilsen features remarkably soft water, with very low total alkalinity and very low levels of mineral ions in general. Burton-on-Trent water is very, very hard, very high total alkalinity, and extremely high levels of sulfate ions.

The different water make the hop extract rates and the flavors profiles will differ greatly. If you brew a Pilsner in Burton on Trent, you will get something that tastes very different than the Pilsner you brewed in Pisen.

* This is the city in the Czech Republic, not the neighborhood in Chicago. Chicago water is not ideal for Pilsners -- far too hard -- but is good for other beers.
posted by eriko at 2:11 PM on May 30 [3 favorites]


Just learned about bulletproof coffee and this whole issue with molds and toxins including aflatoxin as found in moldy peanuts. What say you metafilter? Time to RTFA

Technically it's Bulletproof® Coffee, because he's a douchebag.

He provides no sourcing on his coffee, so who knows for sure, but his spiel about toxins is likely just him shilling for his overpriced beans.
posted by leotrotsky at 2:21 PM on May 30 [3 favorites]


thank you for this, I just sent the link to 3 of my favorite chemists here at work. I work at a pharmaceutical manufacturing site and most of our processes involve this exact sort of organic chemistry (solvent extractions with an eye to the ion-cation balance; particle sizes and pH balance, etc.).

Many of us are coffee nerds, and one of the chemists I sent the link to famously wrote a snarkily hilarious rant memo that he posted up on the wall next to the office coffee machine a couple years ago that said something to the tune of "considering that the process of making coffee is a simple solvent extraction I find it highly troubling that no one in this place can brew a proper cup!"

he then wrote a sarcastic batch record (which is in essence our template for the "recipe" of proper procedure in a chemical process) and posted that up on the wall next to the machine, where it remains to this day. Well except that someone (not me) has laminated it. It has grown a set of approvals, change control forms and signatures as well and has become a huge inside joke.

I fully expect to see this blog post and the linked publication posted up in the coffee room by the end of the day.

:)
posted by lonefrontranger at 2:25 PM on May 30 [9 favorites]


My wife and I just had this happen after moving a few times in a row. Same method for making coffee; same beans; same equipment; same everything--but the coffee tastes totally different (and not always good different), even though the difference in water flavor isn't that noticeable when just drinking a glass of water straight from the well or tap.

I blame the terroirists!
posted by resurrexit at 2:26 PM on May 30 [2 favorites]


I think beer brewers have this experience as well, that water source makes a tremendous difference in the product.

A short discussion on water and beer.
posted by CheeseDigestsAll at 2:48 PM on May 30


I suppose gas is OK for some...
posted by paper chromatographologist at 4:45 PM on May 30 [2 favorites]


Can they do anything to the water to make Starbuck's not taste burnt?
posted by double block and bleed at 10:06 PM on May 30 [1 favorite]


However, it’s almost impossible for him to control the chemical composition of the incident water. Water’s ionic content fluctuates dramatically depending on region and quantity of rain – and it rains a lot in England.

Is there a reason why using bottled water from particular source can't be a solution for this problem? Breweries are founded upon deep water sources for a reason - water that springs from them comes from rains that fell long time ago and had plenty of time to mix thoroughly, evening out the ion content fluctuations.
posted by hat_eater at 2:11 AM on May 31


I think the real problem is that they're using bath water. That can't be sanitary.
posted by yoink at 7:39 AM on May 31 [1 favorite]


But yoink, they needed the bath salts for flavour. Wouldn't want to throw out the bicarbonate with the bath water.
posted by pulposus at 10:18 AM on June 1


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