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Science in the neighborhood: How to make really good coffee


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Sitting at the end of the long wooden bar, I watch with curiosity as Richie begins his pour. He starts the stopwatch on his cell phone and proceeds to pour steaming hot water over the coffee grounds in a precise choreographed motion. The water hits the grounds and starts to seep through while small bubbles rise up to form a layer of foam in its place. Richie adds the water in successive streams spiraling outward from the center of the grounds, an ounce at a time. The water level rises and then falls. At 2 minutes and 31.48 seconds, there is a mound of dissolved grounds left in the filter and a rich, caramel-colored liquid fills the glass below. For the first time in my life, I find myself eager to taste a cup of plain coffee.

Rich Nieto, or Richie as I know him, is a co-owner of my local coffee bar, Sweetleaf, which is a stone’s throw from my apartment in Queens. Since its opening in the spring of 2008, Sweetleaf has become a staple both in the neighborhood and in my daily life. I stop in each morning for a mocha to satisfy my sweet tooth and for a chat with the baristas who have come to know me as their “local astrophysicist.” Most of the time, we engage in small talk about the day ahead, the weather, or the weekend, but occasionally the conversations wander deeper into what I’m teaching, what they’re reading, or what’s new in the neighborhood. With Richie, these conversations often veer into science.

When Richie decided to open Sweetleaf, he knew very little about the world of specialty coffee. But he threw himself into learning all there was to know about its production and consumption. He identified the variables he had to play with as a barista and started experimenting. On more than one occasion, I’ve stopped in to find Richie enlisting the staff and even a customer or two in blind and double blind taste tests as he played with the settings on the coffee machines. His co-owner, Alfred Arundel tells me, "Richie has always been like this, he’ll spend hours just studying one thing, thinking about what the variables are and how they interact."

His systematic approach impresses me, and we’ve often discussed the importance of th scientific method. While I’ve never stopped to think about the variables he is working with, his baristas are all too familiar with his tinkering. Georgia Sanford has been working in coffee shops most of her life, but was only ever trained to get the same tasting product each time, and not to question whether the taste itself could be better. "Richie started asking why not play with the process and see what happens to the taste? Now not only are all our baristas trained to consistently deliver the best tasting results, but we understand more about the variables and how they affect the outcome."

It was a slow Wednesday afternoon when I discovered three electronic scales sitting neatly in a row at the end of the bar. Seeing my curiosity, Richie walked over to explain they were for a new drink he wanted to offer called a "pour over." Essentially a single serving of coffee brewed to order, a pour over is the coffee world’s return to basics.

Coffee trees grow primarily in a belt around the equator in remote regions at moderate altitudes with mild climates. The beans themselves are actually the seeds inside the fruit of the coffee tree, known as the “cherry.” Unfortunately, coffee cherries don’t all ripen at the same time between trees or even between branches. They must be individually inspected and hand-picked. The cherries are put then through one of two processes, dry versus wet, to separate the beans from the pulp of the fruit. Once dry, the last protective layer around the bean, the husk, is removed and the beans are sorted, packaged, and shipped to commercial customers around the world. Upon reaching local distributors, the beans are then roasted and delivered to retail clients such as coffee bars and cafes where they are finally transformed into your beverage of choice.

Coffee drinks generally take two forms: espresso based or brewed. A shot of espresso is ‘pulled’ by forcing hot water through coffee grounds at 135 pounds per square inch. From beginning to end, water is in contact with the grounds for all of 30 seconds. Contrast this with brewed coffee, which requires upwards of five minutes depending on the number of cups being brewed at a time. The grounds are poured into a filter and the requisite amount of water is added. Then you wait. Drip by drip the water makes its way through the grounds under the force of gravity alone, dissolving the grounds in its path. Cafes tend to brew up to a dozen cups at a time in advance so they add a large amount of water all at once to use the weight of the water to speed the process. However, neither of these methods allow the barista full control over the extraction process.

Extraction is the process of dissolving the coffee grounds in water. When the water hits the grounds, acids are the first chemical components to be dissolved, then sugars and finally, the bitter components. The more grounds that dissolve, the higher the “extraction.” But more is not necessarily better. Too much and the bitter flavor is overwhelming; too little and the coffee is on the sour side. But in between 19%-22% is the “sweet spot” – literally. Proper extraction brings out complexities within a coffee that are imparted during its production but often get lost in more commercial consumption. The percent extraction for a given cup of coffee can vary based on several factors, the most important of which are: the size of the grounds, the time that the water is in contact with the grounds, and the distribution of the water among the grounds.

Brewed coffee is often characterized by uneven extraction. The automated system of passing water through a conical mound of coffee grounds inhibits even extraction. The grounds in the center get doused with the most water and as a result, the coffee from these grounds is over- extracted. Other grounds around the perimeter barely interact with the water at all producing coffee that is under-extracted. And unfortunately the law of averages is no help as the average extraction is often dragged upwards towards 22% into borderline bitter territory.

Espresso, by contrast, is the product of even extraction, but comes with its own concessions. While not automated, the process of pulling a shot of espresso is extremely standardized with little room for variation. In order to have repeatable success (i.e., a consistent product), the grounds must be finer and made up of a blend of beans. The espresso grind size allows water to come into contact with more of the grounds as it is forced through them at high pressure. If the grounds were larger, the water would pass straight through without barely any extraction. Smaller, and more pressure would be required to extract anything at all. A blend of beans is used to defend against noticeable differences in an individual coffee harvest from year to year.

With the pour over, the barista can now control all aspects of the extraction process; the precise timing and distribution of the water can ensure that the grounds are evenly extracted in both time and space. The set up is roughly the same as any filter or drip coffee machine; the difference lies in scale and technique.

At the end of the bar, I watch as Richie measures out 21 grams of coffee beans from a Colombian roast. He puts the beans in the grinder and adjusts the knob to set the grind size. With the touch of a button, the machine whirls to life and the beans are transformed into a coarse powder. Richie transfers the coffee to an inverted conical ceramic cup that sits atop a glass receptacle on one of the scales. The cup has a nickel-sized hole in the bottom and is lined with custom-sized filter, which Richie has dampened with water so that the filter sticks to the wall of the cup. He fills a small kettle with twelve ounces of hot water and tilts it over the coffee grounds.

As he pours the water, he explains that he is pre-wetting the grounds, "The point of the pre-wet is to get the coffee ready to receive the water. There’s a lot of carbon dioxide trapped in the grounds so we have to de-gas them first." As the hot water hits the grounds, it forms a layer on the surface before it starts to drop and seep through them. He gives the grounds a stir to wet them evenly and the water begins to bubble and foam as more and more carbon dioxide is released.

When the water level drops to just about level with the grounds, Richie picks up the kettle again and starts his stopwatch. This time he adds a couple of ounces of water to soak the coffee again and then he begins his pour.

"I’m going to work in a circular motion, starting from the center and making bigger and bigger circles around it. By doing this, I’m controlling a few different things. One, I’m controlling the time of the extraction [the time that the water is in contact with the grinds]. And two, I’m controlling the distribution of the water. If I fill the water all the way up, I can speed it [the extraction process] up. If I only put a little bit [of water in], I can slow it down. What I don’t want is for the water to drop below the coffee because any coffee that’s not touching water is not extracting."

Richie adds two ounces at a time, each one in an expanding spiral pattern. Gravity draws the water down through the grounds, dissolving them along the way, and drawing their rich flavor out and into the glass below. After the third spiral pour, he puts the kettle down and picks up a teaspoon. He gives the mixture a stir, creating a small vortex. "This little whirlpool here is going to keep the coffee grounds in the center and off of the side of the walls. The most important part about the brewing process is that all the grounds be in contact with the water," he explains.

The stopwatch is still running, approaching two minutes and thirty seconds, Richie’s target time for the water to have completely filtered through the grounds and into the cup below. At only 1.48 seconds past his mark, the last of the water flows down into the glass below leaving behind a small, porous dome of dissolved grounds.

Richie can tell when he’s between 19-20% extraction now by taste alone, but when he was learning he had to rely on data – scientific data. He bought a refractometer to measure the total amount of dissolved solids in the resulting cup of coffee and he has a program that can translate this number into the percent extraction. He spent well over fifty hours perfecting his technique, but through research, conversations with other baristas, and experimentation, he began hitting the sweet spot again and again. As Richie says, "When you’re converting coffee beans into a cup of coffee, you can play a major role in what that ends up tasting like."

As a novice with a sweet tooth, I’ve never strayed from my preferred mocha, fearing the bitter taste I associate with straight coffee. I admit that impression is at least a decade old and I can’t recall the last time I gave coffee a chance. So after witnessing my first pour over, I was eager to taste coffee again for the first time. The sweetness hit me immediately and the subtle layers of caramel were immediately apparent. It was so smooth and rich and complex. As clichéd as it sounds, I’d never experienced anything like it. The pour over is a drink that tells a story. It captures all that the beans have seen and reveals how each part of the process has left its fingerprint. After tasting my first pour-over, my mocha tasted like a chocolate milkshake.

Image: Coffee Pour Over, by Kate.moon at Wikia Coffe Wiki

About the Author: Summer Ash is currently a postdoc at Columbia University in the Astronomy & Astrophysics Department and an instructor for Frontiers of Science in the Core Curriculum. Her doctoral research was on the evolution of radio galaxies and active galactic nuclei. She values the power of the scientific method, the history of science and the necessity of skeptical inquiry. As a self-professed space cadet, Summer grew up dragging friends and family out at all hours of the day or night to look up at the sky. In her previous life she was a rocket scientist, but now enjoys getting paid to spread her love of space with anyone who will listen. She attempts to blog at Newtonianism for the Ladies, tweets as @Summer_Ash, and is the in-house Astrophysicist for The Rachel Maddow Show.

The views expressed are those of the author and are not necessarily those of Scientific American.

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Comments 33 Comments

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  1. 1. jangchup 2:41 pm 03/8/2011

    You neglect the properties of the filters used. You don’t even mention the French press where the grounds swirl in the water making equal contact for the brewing time. Nor does your supposedly scientific discussion go into the older methods such as boiling and percolation.
    This ends up being just a poor piece of fluff rather than an illuminating discussion of coffee.

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  2. 2. eaglewoman59 3:23 pm 03/8/2011

    Summer, This is excellent, and completely in line with a recent post by America’s Test Kitchen on coffee-making. QUESTION: As you indicate, THE SIZE OF THE GROUNDS is a prime variable. But then you don’t tell us what that should be. How many seconds in a burr grinder or a blade grinder to reduce coffee "cherries" to the best size? Or descriptively—fine? medium? coarse? very coarse? I love it that one can do this at home without expensive hardware. Thank you!

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  3. 3. doclark 3:39 pm 03/8/2011

    Thank you for the interesting article. You covered a lot of variables. I’m guessing that different models of grinders would create different sized particles, and this is just one of the things to experiment with at home. I’m also guessing the brand and the roast of the coffee beans would also be a local variable. Looks like I’ll have to start experimenting this Sunday morning while making brunch.
    You are one of the few people who can accurately answer this question: Is this rocket science or is this not rocket science?
    Congrats on the Rachel Maddow in-house residency.

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  4. 4. Geoff 3:41 pm 03/8/2011

    Some things simply don’t deserve mention in a quality article. For anyone with a taste for good coffee, the French Press is a tool of the devil. Even the Greeks have given up on boiling, having discovered they like (ugh) Nescafe better. And percolation? Shame on you.

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  5. 5. eaglewoman59 3:55 pm 03/8/2011

    Aha. SF Weekly in its SF Foodie section published a Feb.3 article about the Japanese V-60 pour-over technique now in use in some coffee shops in San Francisco, Seattle, and a few Starbucks. Like the barista in Summer’s neighborhood, it uses a cone and carefully heated water, versus the $20,000 Japanese siphon machine highlighted recently in a NYTimes piece.

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  6. 6. jangchup 3:08 am 03/9/2011

    Of course, I do not recommend either percolation or boiling, but wherein does a French Press not meet the criteria outlined in the article? The water makes equal contact to all the coffee grounds for an almost equal amount of time.
    Isn’t the title "Science in the Neighborhood"?

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  7. 7. mtgilbert 8:33 am 03/9/2011

    The grounds are not dissolved in water as the article states. At best they are suspended as the water extracts the various chemicals which become the coffee. If your grounds are dissolving in water, you are using instant coffee by mistake.

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  8. 8. Summer_Ash 10:13 am 03/9/2011

    Yes! Sweetleaf uses the V60 also. I was trying to highlight the science of the process instead of writing a technical how-to manual, so I didn’t mention details like this. But you are correct, compared to a Clover or the siphon machine, the price is right! I also neglected to mention that Richie is measuring his extraction using the ExtractMojo app for the iPhone (not sure if this exists for other smartphones).

    To answer your grind question, that’s just another variable to experiment with. Every grinder is going to be slightly different so it’s best to start with the product guidelines and then tweak as you see fit. In fact, Sweetleaf just got a new grinding burr, so Richie is once again recalibrating his process.

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  9. 9. Summer_Ash 10:18 am 03/9/2011

    Thanks I think I’m gonna go with "not rocket science." And, you’re right, there is no shortage of variables to play with. In the end, everyone has their own preferences, but I was primarily interested in how the result could be quantified – especially in the interest of consistency and repeatability (key factors for a barista).

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  10. 10. Summer_Ash 10:30 am 03/9/2011

    True, the grounds are suspended in the water, but by definition, extraction requires dissolution. The 19-22% extraction range means that 19-22% of the grounds are dissolved in the water (by weight).

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  11. 11. mtgilbert 12:50 pm 03/9/2011

    Summer- Thanks for the reply (with which I agree). The paragraph which begins with the definition of extraction should have contained the word "partially" or something similar to avoid giving a false impression about what is actually happening. The coffee (water + extract) itself is a solution, of course, but grounds + water + extract is a suspension. I strongly feel that we scientists (I was a Columbia post-doc once…) choose our words carefully when communicating with the public.

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  12. 12. greeney 2:03 pm 03/9/2011

    That’s silly! Get a French press! Perfect coffee – no fuss.

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  13. 13. oldfartfox 6:26 pm 03/9/2011

    Regardless of specific techniques employed, I am quite glad that Dr. Ash has discovered that good quality coffee, carefully brewed, has no need of any additives at all. Welcome to the wonderful world of straight, unpolluted coffee!

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  14. 14. EyesWideOpen 8:48 pm 03/9/2011

    Call me old-fashioned but I’m always raptured by using a good French Press and quality beans (ground no more than 10 seconds) from the Galapagos Islands Sanctuary and a host of other exotic locales. This is my answer to the endorphin alternative to "medical marijuana" for non-med uses primarily relating to sanity maintenance.

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  15. 15. tlmorrison 11:45 pm 03/9/2011

    Coffee has all the subtlety of a sledgehammer. Tea is a much more varied and refined beverage, with a variety of options that exceeds wine and a history that is at least a couple of thousand years older than coffee. In addition the caffeine boost of tea is complemented by L Theinine which has a calming effect so that the imbiber is both alert and calm.

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  16. 16. jshove 12:23 am 03/10/2011

    I grew up on coffee. I usually use Mr Coffee drip machine and never thought about water hitting all the grounds equally. I am going to try it with my French press right now. Thanks!

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  17. 17. nparmalee 12:29 am 03/10/2011

    I’ve been using my own pour over method for about a decade (and my coffee is brilliant, if I do say so myself), but now I wonder how much better it could be?!

    What I love about this story is the attitude of bringing science to bear on everyday life. The great thing about a scientific approach is the act of asking a question without knowing the answer, devising a way to test the question, and a way to measure the outcome. Science isn’t only for people with funny hair in white coats. Better coffee through Science. What more noble goal could there possibly be?

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  18. 18. lg_king@earthlink.net 1:47 am 03/10/2011

    I roasted coffee in Oregon for several years in the early ’80s. I don’t think coffee has changed much in the 30 years since then. A few points:

    The coffee will only foam right after roasting. CO2 is locked in the cellular structure of the bean after roasting and it will evolve out in a few days. One thing I rarely see emphasized in this type of article is the importance of fresh roasting. Grind it fresh, too. Use it within a few hours of grinding.

    The best coffee is the coffee you like the best! Various brewing methods will emphasize different flavors and textures. The resulting beverage contains a mix of dissolved and suspended substances, depending on the brewing method used the mix will be different. Its like choosing between original and homestyle orange juice. Avoid coffee makers with the basket type of filter they give a terribly uneven extraction. The Melitta or Chemex cone is a much better system. I use the electric maker in the morning, but for a special treat I grind the coffee by hand in my 50 year old Zassenhaus grinder and pour the water by hand- it does make a difference.

    Espresso- there is no reason why espresso has to be perfectly consistent in flavor from year to year or hour to hour. There are a whole range of flavors that are pretty good. "Consistency is the hobgoblin of little minds." It does need to be dark roasted or it comes out way too sour tasting. I suspect that a fact checker ran this past the giant Italian coffee company who’s CEO wrote a self-promoting article on coffee in SA a couple of years ago. Hopefully, the NPG version of Scientific American will weed out this type of writer in the future.

    It seems like the most precise way to determine the extraction percentage is by weighing the coffee before and after brewing (after drying to the same moisture level). Of course the coffee would be long consumed by the time you got the information so the refractometer reading seems like a good proxy. It would be interesting to see how consistently it really corresponds with the percentage by weight.

    Anyway, these are fine points. You really packed a lot of accurate information into a very short space. I pass by Sweetleaf a couple of times a week on my way from Greenpoint to a ballet class I take next to the 7 train. I’ll stop in and say I saw them in the blog!

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  19. 19. dkraft 6:55 am 03/10/2011

    Fluff. True.

    I have been achieving this extraction with proper temperature control in a french press for years.

    I’ve met several barista (not 16 year olds!) who agree that the french press can control this process of 20% extraction. The Pour is a theatric, well worth the experience but the science is in the extraction, one of several strained immersion techniques. There are more practical implementations with better variable control, french press just one of them.

    I’d expect more than a percentage character and a swirly to write a Scientific American piece.

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  20. 20. ddauerbach 8:46 am 03/10/2011

    Nice piece, despite the carping comments. French press is a perfectly worthwhile brewing method, but it produces a different flavor profile than a pour-over or even a vacuum pot.
    About grinding: Size is crucial but so is uniformity; you need uniformity to avoid channeling (and hence uneven extraction). And you only get uniformity (and repeatable size) with a good burr grinder.

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  21. 21. Summer_Ash 12:17 pm 03/10/2011

    Thanks for your insights. A full treatise on the science of coffee would clearly include details on all stages of the production process, such as roasting like you mention. However, this piece was written to emphasize a scientific approach being used where you might least expect it, i.e., your local coffee bar. The background information was provided mostly for context and to stress how many steps it takes to get from tree to cup.

    As for espresso, I agree that "perfect" consistency isn’t required. I was merely pointing out that it is more often a blend of beans (versus single origin) for consistency as a consumer product. Of course if you are making espresso for yourself, you are free to use any beans you like.

    And the full quote is: "A *foolish* consistency is the hobgoblin of little minds" – Ralph Waldo Emerson. Places of business, like Sweetleaf, tend to strive for some level of consistency to keep customers coming back, which is far from foolish in my book.

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  22. 22. DougAlder 12:57 pm 03/11/2011

    Nor was mentioned one of the single most critical factors in making a good cup of coffee, the temperature of the water. The ideal temperature for extracting the right aromatics is 93C (200F). Never ever use boiling water. Also the use of paper filters, particularly if making a single cup, can affect the taste negatively. The wetting of a paper filter is not to stick it to the wall of the filter holder but to partially remove the paper taste (suggest filling the filter completely with hot water and let it drain then add your ground and proceed.

    If you can find Kenneth David’s book Coffee – it’s highly recommended

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  23. 23. JSR10021 3:14 pm 03/11/2011

    Though I’m not an astrophysicist, my biochemistry PhD is yearning to point out a couple of, uh, issues. For one, you write "…dissolving the grounds in its path." Of course, the grounds don’t dissolve, only those components of the grounds soluble in hot water dissolve. After the water goes through, what’s left is exactly what didn’t dissolve. Second, I have to call a bit of BS to the carbon dioxide left in the beans. Ground coffee beans are air tight? How else could CO2 in there not get replaced with air? Just because adding water to the ground beans gives bubbles doesn’t mean there was CO2 in there. Just means there was something around that could form a bubble when the air went in, like when the baristas foam milk with steam…
    Whew, that feels better.

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  24. 24. lg_king@earthlink.net 10:33 pm 03/11/2011

    The comment about CO2 is based on empirical experience. Immediately after roasting the coffee doesn’t just foam a little bit, it ERUPTS with frothy foam. This effect dissipates after a few days. If you have never hand poured hot water on to truly fresh coffee you may never have seen this. In the 70s Michael Sivetz "Coffee Processing Technology" was the definitive source for information about the roasting process and my memory of reading that is where I get the idea that the gas is mostly CO2. That little valve on some coffee bags is there to let the coffee de-gas without blowing up the bag, otherwise you can’t really seal the bag tightly if you pack the coffee right after roasting.

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  25. 25. Rich Nieto 5:31 pm 03/12/2011

    I don’t think there is a need to be rude. But to answer your questions, the filter is bleached white paper which help produce a cup with a lot of flavor clarity. As far as the French Press goes I am no longer a fan, especially of the normal coarse grind and four minute brew time which is commonly used. Most coffee professionals I know also have moved away from the French Press because as coffee has gotten better we want a brew method that clearly brings out the flavors the coffee has to offer. French Press has very little flavor clarity. The flavors tend to be muddled and that is something I don’t want in my coffee. I have found other less orthodox ways of brewing with a French Press that I find better but that is another discussion.
    FYI if you brew with a coarse grind in a french press your coffee is certainly under extracted.

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  26. 26. Rich Nieto 5:39 pm 03/12/2011

    Grind size is one of the most difficult things to communicate accurately. Especially if you want to be precise. Fine, medium, coarse will get you in the ball park but hardly to your seat. When it comes to pour over coffee, it is easier to communicate in time. When Summer came to Sweetleaf I was brewing 12 oz of water and using 21 grams of coffee. I prewet the beans with about an 1 1/2 oz of water, wait about 30 sec for the coffee to degas (I am assuming you have freshly roasted coffee and are grinding yourself) then pour for about one minute and the water should be done pouring through the coffee in another minute (2 mins total).
    Begin time is when you pour after preset so if you pour for one minute (it’s ok to take short pauses) and the brew time is three minutes then your grind is too fine. If it take 1:30 then your grind is too coarse.
    These are times for 12 oz if you do 24 oz it should take about twice as long.
    Hope that helps.

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  27. 27. Rich Nieto 5:43 pm 03/12/2011

    I would say the perfect coffee is the one you enjoy most. Having said that I would suggest you try a properly brewed pour over and make your decision. I personally find a pour over on a v 60 is far superior to any french press I have ever tasted and I used to love French Press.

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  28. 28. Rich Nieto 5:44 pm 03/12/2011

    Amen!

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  29. 29. Rich Nieto 5:55 pm 03/12/2011

    How do you know you have achieved 20% extraction? French Press is normally underextraced to about 15-17%. Speaking to baristas (regardless of age) without some way of scientific measurement doesn’t really mean much. If you do want to extract to 20% with a french press you have to grind much finer than what most people(including baristas) do. When I do make a french press I use about the same grind I use for a pour over which is way finer than where grinders have their french press setting.

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  30. 30. Rich Nieto 6:00 pm 03/12/2011

    200 degrees is the stand temperature for brewing but with pour overs you have to go higher to about 206 to compensate for the heat loss since the brewing vessel is open.
    The wetting of the paper with brew temp water has three purposes:
    1) remove the paper taste
    2) helps paper stick to the wall
    3) helps heat the brewing vessel to reduce heat loss while brewing

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  31. 31. lg_king@earthlink.net 8:59 am 03/13/2011

    I don’t think I should make any more comments until I stop by and actually try the pour-over!

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  32. 32. hslade3 7:34 pm 04/4/2011

    Rich,

    Just wanted to say good job on replying to previous comments and that the author did a best-than-most job of writing the article. Nowhere near enough credit is given to the baristas that have been shaping the end-user side of the specialty coffee industry over last few years (of which, it sounds like you are one). It next to impossible to explain, even to the highly educated, in a single sitting, the realities of concentration area and grind size particle dispersement, much less the nuances of freshness, seasonality, or even the muscle memory of doing the exact same dialed-in cup recipe thousands of times. No matter how many scientists tell you that "X parameter" doesn’t matter or that you are interpreting the data wrong, YOU know the coffee in your shop and you know what is ending up in the cup. We’ve used the ExtractMojo in our shop for the last year or so and honestly, if one is not using a refractometer, there is absolutely no way to know what the extraction is. Such is the practice of coffee – much like the practice of medicine – a work in constant progress. Thanks for putting in the hours and caring about what goes out from your bar. Would love to have you write an article about this whole experience for our coffee site, dirtycup(dot)com. I think you will find welcome company there. Do what you do, brother.

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  33. 33. hslade3 7:38 pm 04/4/2011

    And by the way, Rich, we completely agree – french press is an inherently flawed brew method. The concentration area is too spread out and underextraction is nearly unavoidable. In fact, a $14-$20 a lb coffee is wasted in a french press because all of its clarity (that you paid for) is just right out the window. The best that can be done to get close to 20-22% is to over dose the crap out of it and grind it beyond all recognition. Ultimately, that’s exactly what you get in the cup – a mug of incognito coffee – a true cup o’ mud. We took all the presses off our bar.

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