Archive for the ‘Espresso’ Category


  • Are You Afraid of the Dark?

  • August 13th, 2013
  • Currently the predominant style in high-end, artisan roasting is certainly light roasting or medium-light roasting, which allows the roaster to highlight the character of the bean rather than the roast.  However, there is no question that many coffee lovers still prefer the bittersweet bite of dark roasts, even if the subtle varietal characteristics have been muted by darker roasting.

    In the early days of Coffee Review, I often resorted to more familiar cooking analogies to explain the impact of roasting on coffee taste.  For example, I compared roasting coffee beans to toasting bread.   At the simplest level, I would explain the some people like their toast barely warmed and others prefer it nearly black.  The barely warmed bread tasted more like, well, the bread, while the blackened toast may make the taste of the original bread unrecognizable.

    The analogy inevitably was extended to consider the type and quality of the bread, which might inform how to toast it.  If the bread were a hearty pumpernickel, it’s character might be maintained or even enhanced during longer (and/or higher temperature) toasting.  The argument went that big, distinctive Sumatras, for example, could handle darker roasting better than, say, a mild Kona.

    The point of all of the analogies wasn’t to convince the consumer to choose a lighter roast, rather to help them understand the impact of the roasting on their coffee tastes.

    When I was in the mood for a livelier debate over the merits of dark roasts, I would draw the analogy to cooking steaks.  In this analogy, clearly dark roasting is considered a bad thing.  Even if most chefs and steakhouses will cook a steak to medium-well or well-done if asked to do so, they probably don’t show a grayish brown steak in their marketing materials.  In fact, most people cringe at the thought of cooking a Wagyu Kobe rib-eye steak to “well done.”

    For my tastes, the steak analogy holds for dark roasting high quality coffee beans.  Personally, I want to taste the terroir, the distinctiveness of origin, and the hard work of the coffee farmer appropriately enhanced by a tactful roaster.

    My personal preferences aside, I was interested in looking at how Kenneth Davids and Coffee Review actually score dark roasts relative to lighter roasts.   Kenneth addressed the issue as early as our June 1999 article titled Extreme and Not-So-Extreme Dark Roasts.  Quoting Kenneth from the article:

    I often am accused of “not liking” dark-roasted coffee. Whereupon I try to explain that what I don’t like are bad dark roasts: thin-bodied, burned dark roasts. Tactfully developed dark roasts, those in which the sugars have been caramelized rather than burned and in which enough fat survives to smooth the cup, are fine with me. And if some nuance also survives, or better yet, transforms in some interesting way under the impact of the roast, so much the better.

    The problem may be that many coffee lovers, and even a few coffee professionals, don’t understand that, at least up to a point, it’s not how dark you roast the coffee, it’s how you roast it dark. You can roast it slowly and sensitively, keeping the temperatures in the roasting chamber from escalating at the end of the roast, or you can, essentially, burn it and destroy it.

    I admit that I do have difficulty appreciating “French roast” blends, the consensus name for blends brought to the very most extreme dark end of the roast spectrum. No matter how skillful the roastmaster, very little tends to survive with these roasts except a rather thin-bodied bittersweet sensation.

    There is, of course, something attractive in the right kind of burned taste. And certainly bitter combined with sweet is a paradox that runs pleasurably through human cuisine, from sweet-and-sour East Asian dishes to Campari to bittersweet chocolate. But I often wonder whether people who buy French roasts wouldn’t be happier with roasts that are a little less extreme, and preserve a bit more sweetness, brightness, and nuance to go with the bitter tones. Perhaps they don’t understand what to ask for, and buy “French roast” because they’re not fully aware of the range of possibility on the dark end of the spectrum and don’t have names for those possibilities.

    You can read the complete article and reviews at CoffeeReview.com.

    In that cupping, the highest rated coffee earned 88 points, which is a solid score but far lower than the highest scoring coffees on Coffee Review.  What do we see if we look at all of the dark roasts that Coffee Review has reviewed over the years?

    Using the advanced search tool on CoffeeReview.com, you can see that Coffee Review has reviewed over 1,000 coffees that are classified as “medium-dark,” “dark,” or “very dark” as measured by their agtron numbers.  If you’re not familiar with agtron readings, you can learn more on our page about interpreting reviews.

    Of the more than 1000 dark roasts reviewed, 276 scored 90 points or higher.  That’s solid.  Of those, only three dark roasts earned 95 points, all of which were medium-dark roasts:

    Maui Mokka Peaberry by Rusty’s Hawaiian Coffee – 95 points, June 2012.

    Espresso Nuevo by Paradise Roasters – 95 points, August 2011.

    Kenya Peaberry Muthunzunni Estate by Atomic Café Coffee Roasters – 95 points, January 2011.

     

    Among “dark” dark roasts, there were numerous coffees that scored 90 points or higher, though with less frequency.

    Natural Decaf Espresso by Caribou Coffee – 94 points, March 2007.

     

    There was one 93-point “dark” roast, also an espresso:

    Organic Espresso N. Italian Style by Thanksgiving Coffee, 93 points, March 2005.

     

    Looking at the coffees categorized as “very dark,” several managed to score 92 points, again, all espressos:

    SWP Decaf Espresso by Portland Roasting, 92 points, March 2007.

    Organic Decaf Espresso by The Supreme Bean, 92 points, March 2005.

    Organic Yemen Mocha by Bartlett’s Premium Coffee, 92 points, August 2003.

     

    It’s interesting to note that all five of the highest scoring “dark” and “very dark” coffees were espressos.  I don’t find that surprising.  Dark roasts with lower acid levels tend to show well with espresso brewing, especially if presented in milk.  However, 3 of those 5 espressos were decaffeinated coffees.  That is a bit surprising.  I’d be curious if any roasters or baristas have observed a similar pattern that might suggest a beneficial link between dark roasting and decafs for espresso brewing.

    One other observation that relates back to my earlier comment about pumpernickel toast, of the coffees that are listed above, the three single-origin coffees are bold, distinctive coffee beans: A Kenya and two mochas, one from Yemen and one from Maui.  It seems that these bold beans held up very well to tactful dark roasting.

    Are you afraid of the dark?  Let us know your thoughts about dark roasted coffees and other roasting analogies.


  • How Does One Rate Milk!?

  • July 3rd, 2013
  • We’re currently testing new capsule espresso systems for July’s featured article.  There are three: the Starbucks Verismo, the Keurig Rivo (with coffee capsules produced by Lavazza), and a dark horse, the Singolo, with machine and capsules produced in Italy and imported by a Canadian company with distribution in the United States. We are benchmarking these three systems against the dominating diva of the category, the well-established and very successful Nespresso system.

    One of the major difficulties faced whenever one tries to review proprietary coffee systems is how to maintain a level playing field when evaluating coffees produced by different machines and systems. The most dramatic example of that difficulty among this month’s three systems resided in the milk heating and frothing functions.

    And, in the case of the Starbucks Verismo system, the identity of the milk, since the Verismo comes with its own proprietary milk capsules. I am sure that in Starbucks meeting rooms far above the folk who know something about coffee, the idea of selling proprietary milk as well as coffee (We can sell the milk too! Holy cow [sorry], that way we can sell twice, no, three times, no four times as much product!) was a persuasive bottom-line argument, bolstered by the idea that milk capsules remove the guesswork element from the beverage production. And, indeed, the photocopied “Reviewer’s Guide” to the Starbucks system was a superb model of clear, engaging communication.

    But the milk! It is beyond bad; basically, it is no exaggeration to report it tastes like detergent and old sponge, and utterly ruined any potential positive characteristics imparted to it by the Starbucks espresso capsules.

    Turning to milk delivery with the other two tested systems, the Keurig/Lavazza Rivo comes with a click-in milk-frothing jug that lets you choose your own milk, and which performs very well, almost as well as the stand-alone milk frother for the Nespresso system. In cappuccino mode it produced an impressively dense micro-froth.

    And the Singolo? Hey, you’re on your own when it comes to milk, friend, because this is an Italian machine and from an Italian perspective drinking espresso with hot frothed milk is a habit mainly limited to children and Americans.

    So, when we came to evaluating the espressos delivered with these machines in the “With Milk” category, what were we to do? On one hand, we could accept the milk option presented by each of the systems. Use the Starbucks milk capsules with the Starbucks espresso capsules, whole milk in the Rivo milk frothing jug with the Rivo/Lavazza capsules, and for the Singolo … what? Heat three parts milk to 150F as we usually do, using the steam wand on our La Marzocco, I suppose.

    My colleague Jason Sarley argued that this approach would not be fair, because the Starbucks coffees would labor under a huge disadvantage and because they would constitute exceptions to our general testing protocols. On the other hand, I argued that scores arrived at using whole milk properly steamed would mislead beginning consumers tempted to buy the Verismo system.

    I ended agreeing with Jason, though we decided to insert a caveat at the beginning of each review of a Verismo capsule warning consumers that using the Starbucks milk capsule reduced the overall rating by a minimum of two to three points. This is a number we arrived at through testing, by the way, in which the same coffee prepared with steamed whole milk consistently scored 6 to 7 for the With Milk category, but 4 when we used the Starbucks milk.




  • Are Espressos A Bargain?

  • June 18th, 2013
  • Coffee Review evaluates and rates coffees that are intended for both espresso and non-espresso brewing.  We are agnostic on brewing method from the point of view of rating a coffee.  So, it’s reassuring to see that the average posted score for espressos (92.10) by American roasters in the first half of 2013 is nearly identical to that for non-espressos (92.14).

    However, the average price of coffees intended for espresso brewing was dramatically less than than that for other coffees.  The average price for espressos, most of which were single origins, was $18.99 per pound.  The non-espressos averaged $24.32 per pound.  That’s a difference of $5.33, or more than 20%!

    Yes, we’re dealing with only 6 months of reviews so it’s possible that it is just a statistical anomaly.  However, looking at the data in more detail, it appears that high-end outliers drive much of the higher cost of non-espressos.  For example, we see a handful of outstanding Hawaiian coffees that cost upward of $50 per pound that we just don’t see as espressos.  We see expensive luwak or civet coffees that typically aren’t intended for espresso brewing.  High quality, more expensive Cup of Excellence coffees seem to appear more frequently as non-espressos than as espressos.

    However, even normalizing for these outliers, espressos are still almost $2 per pound less expensive than non-espressos.  Why is that?  Is it a conscious effort?  Do American roasters as a whole focus their resources on non-espressos?  Do they put their best and most expensive beans in non-espressos?  Or can they simply charge more for non-espressos?

    What are your thoughts?

     



  • The Presso Non-Electric Home Espresso Machine

  • August 24th, 2011
  •  

    If you frequent any one of the high end specialty coffee shops around the country these days you have observed the popular revival of manual, hands-on brewing. The movement has spawned books and blogs and even contests world-wide, but I think that the most beneficial thing to come out of it all is the consumer education that happens when the barista shows off their methodology while talking about their technique and the coffee that they are serving. This in turn creates not only customer loyalty, but also serves to inspire people to want to create great coffee at home themselves using the same techniques and equipment that their morning cup is created with. I find that the simple design of the manual brewing devices adds an intimate connection to my morning cup and the brew time and technique myself encourages a more direct and sensory connection to the process. Unfortunately the manufacturers of these devices had somehow seemed to forget one of the fundamental café experiences,–espresso.

    There have been home “espresso” machines on the market for a long time now and the refinement of their capabilities and the advent of “pro-sumer” machines have put the ability to pull a great shot into the hands of the home barista but the price tags are large enough to keep most impassioned coffee lovers at bay. The closest thing I had found to a manual, inexpensive, “espresso” brewer was the Mokka pot, which produces something close to espresso if you pay close attention to the brew cycle, but makes it very easy to accidentally produce a bitter, over extracted, beverage. Then a friend of mine introduced me to the Presso Espresso Machine. I was hugely skeptical when I first started playing around with it, but being such a coffee geek I couldn’t help but experiment. I was pleasantly surprised at the results that I achieved: authentic espresso.

    The Presso is a well-made machine requiring no electricity and only a small dent in your bank account. It retails somewhere in the neighborhood of $150.00. It is light-weight and small enough to throw in a backpack to go camping and is attractive enough to keep out on the kitchen counter. I found that it produced a good ristretto shot of espresso but there is a method that I found personally to be somewhat essential to follow. It works well for me to consistently get proper extractions however I would highly encourage experimentation.

    What you’ll need is:

    1. Coffee that was roasted no more than two weeks ago. I find that the fresher the better if you want really thick crema. I prefer to use coffees that have been roasted about two to three days prior to brewing.
    2. A burr grinder capable of grinding coffee fine enough for espresso. Not all grinders can grind fine enough no matter what the quality or cost.
    3. An electric or stove top kettle in which to boil water. The water should be cool or room temperature to start with and filtered if possible.
    4. An electronic scale is a nice thing to have around to weigh the dose of coffee but the scoop that comes with the Presso works well too.

    The first thing you’ll want to do is preheat the Presso. Fill up your kettle and bring some water to a boil. Since the Presso is made of metal it will act as a heat sink causing the water to drop from the desired extraction temperature which is around 200 degrees Fahrenheit. Lower temperature extraction produces sour tastes in the final brew. With the arms of the machine in the down position pour boiling water into the water chamber all the way to the top, being careful not to scald yourself. The chamber has small openings on either side of the levers so having a kettle with a small spout works better because it allows for more control of the water stream.

    Place a glass at least six ounces in size under the portafilter.  Next pull the levers all the way up in order to draw the water into the chamber. Do this slowly to avoid spilling the hot water out of the top then press the hot water out of the chamber by pushing the levers down. You have now successfully preheated the Presso. This step also serves to clean the Presso from any residue from previous uses.

    Sometime between setting the water to boil and actually pouring the boiling water into the chamber to preheat the Presso you will want to grind your coffee. I use about 18 grams for a 1.5 ounce shot of espresso. If you don’t have or want to use a scale the scoop that comes with the Presso holds about 9 grams of ground coffee when you level it.

    It may take several attempts to find the grind that works best for you. Too fine a grind will stop the water from going through the bed of ground coffee, and forcing the arms down in the face of such resistance may damage the machine. Too coarse of a grind will result in the water gushing past and under extracting the coffee and create a thin, bitter brew. What you want is a steady, narrow, tapered stream of coffee that appears thick and viscous.

    Now that your Presso has been preheated remove the black handled metal brew-basket called the  portafilter from the body of the machine, wipe it out with a clean dry towel and scoop the coffee in. Eighteen grams of coffee seemed to produce the best results and will most likely end up creating a mound protruding from the top of the portafilter, but you can use a finger to evenly distribute the coffee in the basket. Sometimes a light tap on the side may help as well. Now take the scoop, which doubles as a tamper, and use the back of it to evenly compress the coffee down into the portafilter. The scoop works okay for this step but if you find yourself attached to your new brewer you may want to invest in a 49 millimeter metal tamper, available through web sites like http://amzn.to/p7EDbg.

    Lock the packed portafilter back in the machine securely and place a receptacle for the brew underneath. Add the water just off boil into the chamber only this time filling it up to the top of the two cups that are just above the fill line for a double shot.  Filling it to the line just below the two cups didn’t produce the beverage that satisfied my taste and I believe that a bit more water helps to create more pressure during extraction and provides a bit more heat stabilization.

    Now slowly lift the arms all the way up then press them down until you start to get some coffee dripping into your cup. At this point bring the arms all the way back up, and press then down all the way until you gotten the desired 1.5 ounces of brewed coffee. During the extraction you will notice that the stream of coffee lightens color and this is a great indicator of when you have extracted all the good tastes and aromas from the bed of coffee. I always stop the extraction when the stream starts to turn pale by  stopping the downwards pressure and pulling the levers back up again, because at this point you are just getting a bitter brew and I certainly don’t want any of that in my cup.

    This is, of course, not the only way to use the Presso. Let your inner lab rat get the best of you and experiment with every variable you can think of to find a way to produce a great cup of coffee that fits your palate and style. I think that the ability to do this with manual brewing methods is what makes these methods such a great fit for the coffee geek within as well as for those that just need a really good single cup in the morning to get up and going.

    Clean up the Presso is simple, just knock out the spent grounds from the portafilter into you garbage can and rinse the underside of the machine that come in contact with the coffee and water and you are set to pull your next shot. I think for the price and the results you would be hard pressed to find a better machine to produce your morning shot whether it is at home or in some beautifully scenic state park.

    For more information and tips go to: http://presso.us/


  • What’s a Cortado?

  • June 18th, 2010
  • Recently a Coffee Review reader sent in a request that we post information on our website about cortado, a relatively obscure coffee beverage in North American cafés. I searched the reference pages, thinking some mention of it had to be buried in the “espresso cuisine” section. But no, no cortado was to be found.

    Most serious coffee drinking café denizens are able to precisely define the differences between espresso and macchiato or latte and cappuccino without the blink of an eye. Cortado, on the other hand, is one of those second tier beverages like café con panna or an affogato. Sure, professional baristas will know what these are, but average coffee consumers are bound to draw a blank. By second tier I simply mean that these beverages are not often found on the menus of cafés in North America and therefore less frequently ordered, though they certainly have the potential to be delicious.

    In Spanish, as in Portuguese, the word cortado translates to cut. In the case of the coffee drink, cortado is simply a serving of espresso that is cut with an equal part, or slightly more, hot milk. Typically a cortado is served in a small glass with very little, if any, froth. The cortado is common in Spain and Portugal as well as various Latin American countries. Naturally, alongside the diaspora of these cultures, cortado can be found in restaurants and cafes throughout the world.

    Over the past half century, in the United States at least, coffee cup sizes have steadily crept up from six to eight ounces, then twelve to sixteen, and now twenty and even a mind boggling, heart pounding thirty ounces! Consumer demand and a desire for higher margins seem to be the drivers behind this escalation. In this climate, weighing in at about four ounces, little room is left for the diminutive cortado in most mainstream cafes.

    Of course not all cafes fall into lock step with mainstream coffee trends, and recently there has been a small but distinct backlash against the “bigger is better” movement. You may recall the momentary flurry of media attention that Chicago based Intelligentsia received a couple of years ago when it decided to stop serving coffee in twenty ounce cups. An increasing number of cafes are focusing on a more basic, perhaps more traditional, assortment of coffee sizes. With ristretto shots of espresso and five ounce traditional cappuccinos, the humble cortado could fit quite comfortably on the menus of these cafes. In fact, it is increasingly available in select cafes but often served with more froth on top than a traditional cortado and occasionally with different names such as Piccolo or Gibraltar. Even when not listed, it is usually possible to order cortado off the menu.


  • Porta-filter densation

  • June 13th, 2010
  • I was talking to Scott Callaghan the Australian barista champion just before he left for London for the World Barista Championship and I mentioned to him about “densation.” It’s a clumsy word but its similar to the principle that occurs with the sorting of green beans in a good dry-mill where you have a ‘densimetric’ table that is on an angle and when it vibrates the larger beans go to the top and the smaller beans and the chipped and broken parts go to the bottom.

    The same thing happens when you are making an espresso coffee when you bang a loaded porta-filter on a bench or as World Barista Champion Paul Bassett calls it: “settling” the coffee.   By banging the porta-filter on a bench or a bar it sorts out the particle sizes of the  ground coffee slightly so you get the bigger particles at the top and the smaller particles at the bottom to some extent.  The finer the grind the less this will occur as the particles are a little more viscous due to the increased surface area and exposed oils.    In other words the finer particles that are impregnated with oils tend to stick together a little more rather than separating.

    Basically what it enables you to do is create a better extraction.

    It is somewhat similar to how some espresso machines maintain a constant temperature at the brew-head by not having a repeated identical interval where the thermostat comes on.  Rather it comes on in ever-diminishing intervals to stop the brew head from getting too much momentum and over-heating.   A constant series of regular intervals going on without paus actually increases the temperature.  By reducing the intervals to say 0.9 seconds, 0.8 seconds 0.7 seconds etc it will actually maintain a more constant temperature and stop the temperature from climbing.

    As water passes through dry coffee particles in the porta-filter, if there is an apparent even sorting of particles from top to bottom, the water will become a ‘saturated solution’ very quickly.  And once you have a saturated solution the water can’t actually absorb anything more. That’s the nature of a saturated solution in scientific terms.  (By the way: a saturated solution is actually the main principle by which Swiss Water Process produce their decaffeinated coffee.)

    So what happens as a result of the ‘densation’ effect is that coffee grounds are densimetrically sorted, and the water will flow more easily through the top part of the coffee puck. And when the water comes to the bottom of the coffee it will tend to extract the optimum flavour from there as well as taking some from the coarser particles at the top.  So ironically you actually get a more ‘even’ extraction out of the coffee grinds than you would out of an even particle size distribution.

    One of the other factors that it enables you to do is to grind the coffee a little coarser and that again enables you to sort the particle sizes out better again and that is all, of course, intertwined in a complex way with the brewing temperature which permits a higher temperature which will of course bring out a different flavor profile.  Altogether it creates a slightly sweeter and cleaner style of espresso coffee.

    I should add that I got this idea from Carl Staub of Agtron who demonstrated it for me using a Swift grinder where he served me three espresso shots and he actually adjusted the grinder while it was actually grinding.   So he created the densation effect by adjusting the grinder itself.

    He gave me three shots and the taste difference was phenomenal.  It was like having three completely different coffees.  The first one was great much cleaner and more complex; the second one was just OK, and the third one was not nice at all.  # 1 was coarse at the top and finer at the bottom; # 2 was even from top to bottom, as you would normally have it, and # 3 was fine at the top and coarser at the bottom.

    I was working on developing a grinder that could repeat this in a commercial way with a lovely guy by the name of Mike Del Zoppo who is now no longer with us. He has gone to that espresso machine in the sky, so we never ended up making a grinder that could repeat this time after time but it is certainly a potential new challenge for manufacturers.


  • Espresso. Is Your Coffee Too Fresh?

  • April 19th, 2010
  • As with many subjects related to coffee you will find a variety of opinions regarding freshness within the coffee industry. Take for example the question of storage, for every roaster that recommends storing your coffee in the freezer or refrigerator there are many more that perish the thought. No matter the number of roasters that extol the virtues of hermetically sealed, nitrogen flushed, one way valve bags, there are few industry insiders that would argue it is better to purchase just of one week’s supply of freshly roasted coffee at a time, whole bean, of course, and grind just before brewing. The three, six, twelve or, yes, believe it or not, even eighteen month shelf life suggestions sometimes made by large roasting companies should be reserved for fallout shelters and hermits whose mountainous cave dwellings are not served by local mail delivery or Federal Express. (Although the latter would be better off purchasing green coffee, and roasting it over a camp fire.)

    When the discussion switches from brewed coffee to espresso our collective agreement on freshness diverges further from this arguably common understanding. Anyone who has ever pulled a shot of espresso with coffee straight from the roaster, whether on a home or professional machine, knows that it produces less than satisfactory results. This begs the question, what is the ideal time to wait between roasting and brewing coffee as espresso? I posed this question to a group of professional baristas who just competed against one another in the 2010 United States Barista Championship. The baristas in question are: Southeast Regional Champion, representing Counter Culture Coffee, Lem Butler; Midwest Regional Champion Mike Marquard from Kaldi’s Coffee, and Pete Licata, the Western Regional Champion who currently plys his trade at the Honolulu Coffee Company.

    Let’s look at the easy answer first. If we take the average, this group concludes that one should wait about a week, give or take a few days, before pulling shots. This conclusion is based on the experience of working with the same groups of coffees on a daily basis over the course of years, as well as the rigorous preparation regiments needed to compete seriously in regional and national barista competitions. Lem sums up the ideal range of time coffee is at its peak for espresso brewing as, “6-8 days sealed in its original packaging. Once the packaging is opened and the coffee is exposed to air, the storage time decreases drastically.” Pete adds, “…once a coffee hits its peak it has between 1 and 3 days before the flavors, body, and aroma start to fade.” So it appears that with coffee purchased for espresso, just as with coffee purchased to be brewed by other means, our lesson continues to be, buy fresh coffee frequently. Mike also finds “that anything much over 20 days off the roast really starts to flatten out – both visually and on the palate.”

    Mike suggests that the average consumer wait “…at least 3 days from roast before brewing any coffee as espresso.” Although for barista competitions, he prefers to store his coffee in a sealed bag for, “9-11 days off the roast, and then one extra half-day open.” Pete states that, “The ideal resting time for espresso always seems to vary from coffee to coffee.” So, the more complicated answer, as Pete suggests, is to, “Pay attention to your coffee and you will find its best window.” To illustrate this point, when considering an assortment of espresso blends from Counter Culture Coffee, Lem finds that he prefers, “…Espresso Toscano rested at 8 days; espresso Rustico at 7 days; espresso Aficianado at 6 days and espresso La Forza at 6 to 7 days.” I told you this would get a little complicated.

    What’s with all the variation, you may be asking. A clue can be found in Lem’s belief that it “depends on how long the coffee was roasted.” Pete notes that there are, “major variations in the amount of expelled gas based largely on the roasting technique.” Lem continues this thought by adding, “Longer roasts build more gas inside the coffee bean … Pressurized brewing and lots of gas will produce bubbles inside the crema of the espresso as it extracts. With so much CO2 trapped inside the coffee beans, it will take time for the gas to part leaving the beans to develop more of the sweetness and brightness.”

    This context helps explain the variance in the ideal amount of time to wait before brewing coffee as espresso as compared to other brewing methods. Pete adds that “most roasters use a different roast profile for espresso versus standard coffee. Because of this the resting time may vary.”

    To summarize, the best results when brewing espresso are based on experience and practice. You don’t need years of professional barista experience to figure out how long to wait before brewing espresso coffee. All you need to do is purchase high quality, fresh roasted coffee and try pulling shots every day over a period of time. After a while you will come to your own conclusions and preferences. And hopefully you will always be drinking espresso coffee at its peak of freshness.