ernesthon

29 Mar 2012

Coffee: the art

Latte art has become popular over the past few as a visual indication that the cafe is serving good coffee. Comically, I observed a barista at Second Cup (a chain cafe in Canada similar to Starbucks) try in vain to pour a design into my cup a few weeks ago. He failed because his equipment and technique didn’t create the right type of foam for him to work with. While the possibilities are endless in creating cool designs (like this one from Cafe Castel in Montreal), the standard pattern is either a rosette or a heart. Both of these require no tools and relies only on careful pouring of foamed milk into the shot of espresso.

The quality of the steamed milk is important. The steaming wand needs to be placed barely below the surface to draw in enough air and break up the bubbles into fine foam. If the wand is too deep, then insufficient foam will be created. If the wand is too near the surface, then large bubbles will be whipped in and instead of finely textured micro-foam, there will be large frothy bubbles not suitable for art. After foaming, the pitcher is hit on the counter top to break up any accidental large bubbles. Then a swirl will help to homogenize the milk-foam mixture: you want to avoid separation of the two when it is poured into the coffee. And importantly, the pitcher needs to have a narrow spout in order to control the flow and shape of the pour.

I usually start the pour by going slowly in a couple of circles around the whole cup to mix the dark espresso creama with some foam to get a good brown base (others swear by the partial pour and spoon stir method). Then, going slowly, I rock the pitcher side to side while simultaneously moving it away from the cup to create the leaves. Then when the pitcher is near the end of the cup, I finish the pour by drawing the milk back into the center of the pattern to create the stem of the rosette.

28 Mar 2012

Coffee: the milk

Milk has been paired with coffee probably since its introduction to Europe, some 3 centuries ago. Milk contains many large proteins that bind readily to the tannins in coffee, which reduces the sensation of astringency. Without milk, tannins bind to the proteins in our saliva and reduce its lubricating quality, and therefore makes tannic foods “rough”. Milk makes coffee more approachable.

There are 3 derivative drinks based on the espresso: Macchiato, Cappuccino, and Latte. These all incorporate the basic espresso but varying quantities and quality of milk. A macchiato has only the tiniest amount of milk foam - its name meaning “marked” (with foam). A cappuccino is a balance: 1/3 coffee, 1/3 steamed liquid milk, 1/3 foam. And finally, the latte is 1/3 coffee and 2/3 steamed milk (but no/little foam). There is a common misconception is that Cafe au Lait is part of this group, however, a cafe au lait uses strong french press coffee rather than espresso as its base.

Good foamed milk is a big reason why we go to nice coffee shops and spend so much for coffee. It’s also what makes good machines so big and expensive - they need to be designed to handle the differing requirements of coffee and steaming. Steaming is the traditional method of creating foam and heating milk for espresso drinks. Proteins in the milk have a moderate ability to link together and form networks in order to trap little bubbles of air in the liquid (egg white or heavy cream have much greater stabilizing ability, observe meringue or whipped cream). However, when heated to 70 degrees Celsius, the milk proteins being to unfold and help to better stabilize milk foams.

To create foam with the steam, the steaming wand needs to be placed just below the surface. This allows the high pressure steam to pull in air as it violently hits the milk, therefore causing the bubbles to break up into many tiny bubbles. This is the typical chhh-chh-chh sound of a coffee shop. Milk foams best when its cold and more viscous. Skimmed or partially skimmed milk is also better at foaming (but less rich tasting!). After creating some foam at the surface, the wand can then be plunged into the milk to continue the heating until it hits 70 degrees, when the foam is stabilized but avoids causing “cooked” flavors in the milk.

27 Mar 2012

Coffee: the pull

Espresso is made with water pressure at around 9 to 11 atmospheres of pressure. This intense pressure forces the small amount of water through a large amount of beans and extracts much more of the coffee solids as well as forming an emulsion of oils and carbon dioxide with the coffee liquid. This creates a rich and substantial fluid with a layer of reddish brown foam called crema. Every good espresso will have creama (although not every coffee with crema is good!). Crema is a sign that many of the components are right - the coffee is sufficiently fresh (freshly roasted coffee has a large amount of carbon dioxide in the beans), the pressure and temperature was generally right to extract the proteins, carbohydrates, pigments, and phenolics that make a good cup.

When the pump is turned on, water is forced into the coffee and will take a few seconds before it begins to pass through and drip into the cup. The extraction time should be around 30 seconds, anything too long or too short indicates that something is wrong in the other variables (grind, tamp, etc). It will have a rich reddish brown crema that lingers on the surface of the coffee (not jet black), and will begin to lighten in color as the coffee continues to extract. This is called “blonding” which at a certain point indicates that the machine should be stopped (a medium tan, not a golden blond). The beginning of a shot and the end of a shot are remarkably different - the beginning is dark, sweet, and thick, whereas the end (the blonder portion) is thin, sharp, and contains much more caffeine.

So far, I’ve avoided the use of the word “strong”. Our notion of strength needs to be carefully defined when talking about coffee. Espresso is strong, whereas percolator coffee is weak (or watery). However, on another scale is the issue of under-extracted or over-extracted. This is often mistaken for strength. Bitter and astringent flavors is a sign that coffee is over-extracted or over-roasted, whereas acidic flavors is a flaw when coffee is under-extracted. Over-extracting happens if the grind is too fine, the dose too large, the tamp too hard, the pressure too high, or the water too hot. Under-extraction is the opposite, when the grind is too coarse, the dose too small, the tamp too weak, the water too cool, or the pressure too low.

26 Mar 2012

Coffee: the machine

Coffee is chemistry. When you get a couple important variables right, the end result is indeed a very tasty cup. At the machine and extraction stage, temperature and pressure are the two major variables that determine how good your espresso will be.

What differentiates an espresso from other types of coffee is it’s unique mix of temperature and pressure. Traditionally, coffee was brewed over long periods of time, and extracted out many of the flavor in the bean, both good and bad. These brewed versions were made with finely powdered beans and boiled with sugar and water, like Turkish or Arabic coffee is today. However, in the 1700’s Europeans began to prefer a refined version, using a cloth filter bag and cooler water - so that resulting coffee is less bitter and astringent. The modern espresso only came of age in the 19th century with the invention of the espresso machine, which made its debut at the 1855 Paris World Fair. Rather than letting time extract flavor from the beans, espresso relies on forcing hot water at high pressure through tightly packed beans to bring out a uniquely concentrated and balanced cup.

A machine has to do two important things to make good espresso. It needs to heat water to a consistent 88-92 degrees Celsius, and then deliver that water to the puck of coffee grinds at a pressure of 9 to 11 atmospheres. Espresso machines are also expected to make steam, which is useful for frothing milk. This is harder than you think. Getting water to a precise and consistent temperature and pressure presents several engineering challenges. The temperature required for making steam is much higher than making coffee, and therefore machines that are able to do both proficiently are both expensive and complicated.

A single boiler machine, the cheapest of espresso machines, use a single boiler and pump. After the coffee is made at 88-92 degrees, an element can be switched on to heat the water to above 100 degrees to create steam. However, there is a significant lag time for this and usually results in mediocre coffee and mediocre steam.

The best machines are double boiler machines. These are usually the ones you find at professional coffee shops. It has a boiler tank that produces steam and a boiler tank that is calibrated to keep water at the right temperature for coffee.

A third type, a heat exchanger (HX) machine, also uses a single boiler, but uses a clever system to deal with the dual heat requirement. The boiler is kept at a temperature above 100 degrees, hot enough to generate high steam pressure. The water used for coffee, however, does not originate from the boiler, but instead from a cool water reservoir in the back. When the machine is switched on, cool water is pumped through a metal pipe that passes inside of the boiler, heating the water to the correct temperature before infusing the coffee (thus the heat exchange). This method allows both for excellent steam and coffee without the excess weight and size of a double boiler. However, an HX machine needs a little extra care. Water that is in the section of pipe passing through the boiler becomes superheated and too hot for coffee. Therefore a HX machine needs a “flush”, where the hot water needs to be flushed out of the system with cool reservoir water to equalize the piping to the correct temperature.

I use an ECM Giotto machine, which is an HX machine. The grouphead (the shiny silver part) is one of coffee’s most famous and enduring designs - the Faema e61. This component has been perfected and is common amongst most of the great HX machines. Due to the required HX flush, I’ve installed a thermometer in the grouphead to measure the actual temperature of the water passing through, which allows me to calibrate with precision how much water to flush before the system is at the right temperature.

24 Mar 2012

Coffee: the tamp

If there’s one thing that makes it easy to tell a good coffee shop from a bad one, it is the tamp. To make good espresso you need to have a good tamp, although the reverse is not necessarily true. If this critical part of the process isn’t done, you really shouldn’t be paying $4 for that coffee (unless you’re desperate).

Tamping is where the ground coffee is pressed into the filter basket, ensuring that it is evenly distributed and dense enough to slow the water as it passes through the coffee. I used the north-south-east-west method, this gets all the sides tamped properly because the tamper is slightly smaller than the basket. I then finish off with a sight rotation - a “polish” on the puck of coffee.

23 Mar 2012

Coffee: the dose

Espresso is a really finicky thing. One of the most difficult variables to get right is the dosing of the ground coffee into the filter basket. Coffee grind usually comes out a little clumpy, making it hard to distribute it completely evenly. Dosing is important because when hot water is forced through the coffee at high pressure, it will tend to pass through the path of least resistance. If the basket of ground coffee is not very even in density and level, then something called “channeling” will likely happen. This means that the water will flow quickly through a patch of low density, causing overextraction of that part of the basket, leaving the other parts underextracted. This will result in a coffee that is both bitter and sour at the same time - generally unpleasant.

Everyone has their own little trick of getting the dosing right. I suppose that most of them are right. I use the knife method, where I tap the basket with an edge of a knife to ensure that there are no air pockets, then scrape off the excess coffee. I’ve also seen the plate method, which creates a concave surface, as well as the slight mound, to create a convex surface. In my mind, as long as the basket is filled evenly (in depth and density) and consistently each time, it’s possible to correct for the style of dose in the other stages.

And then there’s also the question of the quantity. It has become vogue to updose coffee, by using a larger basket for the same quantity of coffee. Most people in North America expect bigger drinks (just think about the small juice/soda containers in Europe and Asia) so we generally see “double” shot drinks used as singles.

22 Mar 2012

Coffee: the grind

Probably the most under-appreciated part of the coffee process is the grind. I see so many people care about their coffee, buy great beans, and use a nice machine, but end up getting the local cafe to grind up all the beans at once or use a crummy grinder. The grind is a critical variable in getting your coffee just right - even more so if you intend on making coffee in a french press or pour-over, the grinder is likely the most important (and expensive) piece of equipment that you should own.

Blade grinders are inferior, because it is a simple spinning blade, like a blender, that “chops” the beans until you let go of the button.This produces big pieces and small pieces of coffee - meaning that during the brew process, the small pieces will extract much faster than the larger pieces. Good grinders are burr grinders, that use 2 meshed tooth wheels to crush the beans to a uniform shape and size. The size of the grind will be mostly uniform because only when the coffee has reached a certain size, does it fall between the burrs and down the chute. The best grinders run at slower speeds with large conical burrs that minimizes heat from friction during grinding.

The faster the brew, the finer the grind. Coffee that gets brewed in under a minute, like espresso and moka, need to have a very fine grind to slow the passage of water under high pressure. A french press, which has a brew time of several minutes, will need very coarse grind to prevent over-extraction.

I use a Rancilio Rocky to grind the beans right before use. I can tell from the look and the taste if I’ve ground the beans 20 minutes early - these 20 minutes can make fresh beans taste a week old! So NEVER ask your coffee shop to pre-grind your beans.

20 Mar 2012

Coffee: the beans

I’ve realized that I’ve almost never written about one of my great obsessions - coffee. Some 6 years ago I decided that I was going to passionate about good coffee (even though at that time I didn’t love it all too much) and so I went on to learn everything I could about how to make and enjoy a good cup. Perhaps what got me into it was that coffee is both technical and artistic. What I mean by this is that the making of a good cup is determined by a degree of technical perfection, as well as a measure of personal taste. These too, are shared with cooking and photography, other great pleasures of mine.

The coffee lover today can enjoy much better coffee than they could have five years ago. I witnessed a remarkable renaissance in both Montreal, Calgary, and Vancouver in the coming of the new-age boutique cafe, slowly winning away from the chains bit by bit. The trend seems to be driven by the West Coast and slowly permeating towards the east (like it did in the US, with Seattle, Portland, and San Francisco as coffee pioneering cities). In Vancouver, cafes like Artegiano, 49th Parallel, and JJ Bean were the first to start this renaissance, using high end machines, medium roasted beans, and appropriately sized cups. This was in contrast to the gigantic milky lattes with bitter, over-roasted beans at your local Starbucks. This was followed in Calgary by Cafe Beano, Phil and Sebastian, and Kawa. Today the biggest change is probably happening in Montreal, where pioneer Cafe Myriade has shown the way for Picolo, Caffe in Gamba, and Cafe St Henri.

The Beans….

One of the most important things about coffee is the quality of the beans that you are using. There’s a whole other level of coffee bean obsession that I wont go into - but you’ve got things like altitude, origin, processing, and roasting that ultimately affects the taste. The beans that I like best are from 49th Parallel (Vancouver), Intelligentsia (Chicago), Blue Bottle (SF and NYC), or Stumptown (Portland). Generally the beans not to buy are the ones in the grocery store (Illy, Starbucks, etc) and anything pre-ground. Starbucks roasts their coffee way to the extreme, which burns the sugars and makes for really bitter coffee. Coffee degrades rather quickly, so even good beans that I buy fresh only last me at most 2 weeks. Check the date at the bottom of the bag before buying - hopefully it was roasted within that week. Store the coffee in the fridge (some say never the freezer) in a sealable bag/box to make it last longer.

30 Jan 2012

A fresh bag of 49th Parallel Epic Espresso to start the week. This is one of my favorite brands of coffee beans as I find that their Epic Espresso blend consistently produces good shots. It’s generally on the sweeter side for espresso, but I like that for cappuccinos in the morning. 49th Parallel is perhaps the most successful Canadian roaster, as it was one of the pioneers of the boutique roaster/cafe trend in Vancouver. I’ve found their beans at El Beit in Williamsburg as well as RBC NYC in the Financial District, although I usually buy a bag from Cafe Myriade each time I’m in Montreal.

A fresh bag of 49th Parallel Epic Espresso to start the week.

This is one of my favorite brands of coffee beans as I find that their Epic Espresso blend consistently produces good shots. It’s generally on the sweeter side for espresso, but I like that for cappuccinos in the morning. 49th Parallel is perhaps the most successful Canadian roaster, as it was one of the pioneers of the boutique roaster/cafe trend in Vancouver. I’ve found their beans at El Beit in Williamsburg as well as RBC NYC in the Financial District, although I usually buy a bag from Cafe Myriade each time I’m in Montreal.

14 May 2011

I found a Slayer: RBC NYC

I found a little café on Worth Street, tucked in a bit of a “no man’s land” between Tribeca and City Hall area holding a bit of a surprise. It’s in a gorgeous limestone facade building, with barely any signage, with only gold letters RBC•NYC on top of the doors.

Inside, I found a delightful space that was jam packed with coffee gadgets. It’s a coffee geek’s paradise - they sell a dozen types of beans, and offer coffee by vacuum pot, pour-over, french press, cold brew, and of course - espresso.

But what really caught my attention was the Slayer. I first encountered the Slayer in Calgary at Caffe Beano about 2 years ago; these machines are incredibly rare (according the the New York Times - only around 40 machines) and exalted to be one of the best espresso machines made. What makes them special is how the coffee extraction can be controlled via wooden sliders, rather than a button or a switch. That means that the barista can control the pressure of the pumps at any point in the extraction of the coffee, rather than relying on the machine to force hot water in an on-or-off fashion.

Go try the espresso if you’re ever in the area! I found it to be very rich and intense, lots of crema, and a touch on the side of bitter. To boot, there’s also a big screen display of a doggy spa swimming pool on live display (not kidding, this is TriBeCa after all).

10 Apr 2010

MTL: Cafés

While Montréal isn’t famous for good coffee (in fact you’ll more likely find terrible coffee), there are a couple of hidden gems in the city for our regular caffeine fix. Some score the points on amazing taste, while others win on amazing style.

1) Café Myriade

Without a doubt, Myriade has the best coffee in town. Opened up sometime in the middle of 2009, Myriade brings the best of west-coast coffee snobbery to Montréal and goes all out to ensure the best cup. Watch the barista pull a shot - it’s a beautiful orchestration of exact measurement, precise temperature and timing, and experienced pour from the milk pitcher.

2) Café Castel

Another of Montréal’s greats in my books, Castel has delicious coffee but adds a little more style. On a lucky day, you might catch Samer working there - he’s an absolute pro at latté art. I’ve posted this (link) before - it’s one of the masterpieces that he’s created that I almost felt too guilty to drink.

3) Café Olimpico, Club Social

In the heart of Mile-end, Olimpico and Club Social are on rue St. Viateur one block from each other. The Italian Montréalers swear by Olimpico and very often you’ll find the clichéd scene of old Italian men squabbling over a chessboard. Sugar in before the milk, a signature of the Italian cappuccino. Both Club Social and Olimpico have a fantastic terrasse - on Sunday afternoons in the summer, you’ll always find a crowd with everyone sipping on iced lattés.