Crema is a little bit of a Holy Grail in the espresso world — folks are talking about it all the time, searching for it, measuring their technique, equipment and coffee by it. But what the heck is it? What does the production of crema give you? And is it really that important?
Some of the bigwigs in the specialty coffee industry (such as James Hoffman) have proclaimed crema to be ‘rubbish’; we won’t go that far, because — like everything with coffee — it’s really a personal preference. When we were at the SCAA convention in April, we went to a couple of lectures that talked about coffee preparation variables and how they effect the end result. From those lectures, we picked up the following tidbits of info that play a part in the formation of crema.
First, let’s define our terms here: Crema is the initial light/tawny colored liquid that comes out during an espresso extraction. It is what causes that ‘Guinness effect’ that folks sometimes reference. As the lighter liquid infuses with the darker liquid that comes after, it filters up and ‘settles’, leaving a tan colored layer on top of the darker espresso below.
The formation of crema is a blend of a few different things: As water is forced through the coffee under pressure, it emulsifies the natural fat/oil content in the bean, suspending it in tiny microbubbles of air. Additionally, after coffee is roasted, it out-gases C02 for awhile (generally for the next 24 – 72 hours post-roast) and so coffee that was more freshly roasted will also emit some C02 during extraction.
As the specialty coffee industry has grown more and more focused on quality, distribution, craft and flavor, crema was a hallmark for two different things: First, the bean’s natural fat/oil content was higher and therefore could be assumed to be processed at the plantation in a preferable manner, and second, that the coffee had been roasted recently enough that it still had some C02 out-gassing from the beans. So espresso enthusiasts became very focused on the creation of crema as the most important element of good espresso.
This isn’t necessarily true. You can pull a beautiful looking shot that filters down and looks quite gorgeous, but that, in fact, tastes quite sour because the crema is the result of post-roast C02. Conversely, you can pull a delicious shot that has no crema at all because of the way the bean was processed at the plantation and how darkly it was roasted. Pressurized portafilters and superautomatics feature technology that aerates the coffee during extraction, to give the illusion of crema, but the flavor doesn’t necessarily back it up.
So here are some parameters to keep in mind in regard to the creation of crema:
- Plantation Processing – Beans that are naturally/dry or pulped natural/semi-washed/honey processed will naturally maintain more of their sugar and fat, resulting in more crema production during extraction. You’ll find beans produced in Africa and Brazil to use these processes, with a movement in other Central and South American growing countries toward ‘Honeyed’ and/or pulped natural processing. Beans from moister climates (such as Sumatra) will have a very different taste and oil content to them because they are most often wet processed.
- Roast Date- How recently was your coffee roasted and how darkly was it roasted? While the ‘sweet spot’ for a coffee post-roast varies, pulling shots with coffee roasted less than 72 hours before will definitely result in an early blonding that is often mistaken for crema. You want some of the C02 for the emulsification of the fat, but not so much that there’s no room for the coffee solids to actually extract.
- Roast Color – Darker roasts will bring more of the bean’s natural oil to the surface, which will then transfer to packaging containers, grinders and your other equipment, resulting in less overall oil/fat in the coffee grounds themselves that can be emulsified. So you will likely often see that darker roasts can produce less crema.
- Espresso Machine Tech – Pressurized porftafilters aerate the coffee during the extraction, giving the illusion of crema. Similarly, superautomatic machines will often utilize technology that will produce the look of crema without it actually being the emulsification of the fat/oil and the C02. This makes these machines ‘user friendly’ but it’s also kind of a hack and often doesn’t taste as rich or complex as shots pulled via traditional extraction methods.
We’re not scientists and we don’t love following rules, but we have been reading and talking about and then experimenting with crema for the last few months, so thought we’d share our current thoughts. Certainly, there could be more to crema than we’re aware and we’re always learning.
What do you think of crema? How have you achieved your favorite shots — coffee type, roast style, equipment? Please share in the comments.
While at the SCAA last month, we ran into the founder and creator of the Behmor home roaster, Joe Behm, and had an excellent conversation with him. We had been thinking about looking into expanding our home roasting options (given that the iRoast is MIA these days) and were interested in the Behmor 1600, so it was great to get the opportunity to see it in person.
Our favorite thing is that it has smoke suppression technology, so you could theoretically use this in your home without your co-inhabitants kicking you and all your freshly roasted coffee to the curb. It is purported to roast between 1/4 lb. and 1 lb. of green beans to a medium roast — although we have heard that it has a tough time with the higher end.
We can’t wait to get them in the store and play around with them — watch this space for a crew review as soon as possible!
Having GI distress after a cup of coffee is more than enough reason for some folks to swear off the stuff. Like so many things around food and how our bodies process it, the subject of what causes such distress is often up for debate. Edwin Martinez of Hario USA & Finca Vista Hermosa posited that the negative reactions to coffee could be based in rancid oils or over-roasted beans. Some folks think that maybe it’s just sheer acidity in the bean itself.
But a new group of scientists who are studying the nutritional benefits of processed foods versus totally raw foods have found that a stomach-friendly compound called N-methylpyridinium (NMP) that appears in coffee beans only after the roasting process actually decreases the amount of acid that stomach cells produce in response to coffee. To test out stomach cell reaction to coffee, they used a combination of water and solvents to extract compounds from some different coffee blends, then exposed them to the cells. Except for NPM, the cells increased their acid production in response to the compounds.
So maybe darker roasts aren’t going to give you the same rainbow of flavors that a medium roast coffee might, but it may be easier on the ol’ tum tum — and if that’s a concern for you, choosing a darker roasted bean may be the key to you enjoying a cup of morning java.
While we have an appreciation for the simplicity of many espresso blends, getting into single origins can be a sumptuous adventure. For his recent Holiday Blend, Velton imported a delicious Arabica from the El Salvador plantation Finca Alaska. This 2007 Cup of Excellence winner is a clean, smooth cup with bright lemon, fig, chocolate and even blackberry notes.
He only has a small quantity left, so if you have a love for single origins and want to try this excellent varietal, we highly recommend picking it up. In fact, during our recent trip to Hario USA, this is the coffee we used to demo the gear and Edwin Martinez noted that it is one of the best coffees he’s tasted in a long while — even bringing it down to the plantation in Guatemala and impressing his counterparts there!
Not sure if Velton’s Coffee is worth the hype? Well, your local church folks sure thinks it is:
With Portland’s Stumptown representing strongly for the West Coast and Durham’s Counter Culture keeping it real for the East Coast, Chicago’s Intelligentsia brings up the middle, melding it all together and offering a similar brand of java-love to folks in the Midwest and beyond. These three companies feature multi-city locations, direct trade values and a commitment to both the art and science of great coffee — to paraphrase Intelligentsia’s David Latourell, it’s about consciousness.
Flavorwire recently sat down with Latourell to discuss Intelligenstia, what it’s about, what the contemporary coffee movement is focused on and what’s next. We loved his references to slowing down and understanding what you’re ingesting, what you’re taking in and why. Sure, a lot of us drink coffee for its caffeine perks, but it’s more than that to a lot of people around the world and it’s good for us to take a step back and appreciate that. We recommend reading the interview — which also includes Latourell’s tips for finding great coffee and great cafes.
Back in May, we wrote a little bit about Italian vs. French Roasts, but lately we have been sampling a lot of different roast and blend types and decided to read more about the basic theory behind roasting and blending. In our research, we ran across Kenneth Davids‘ excellent table describing the different roast styles and their corresponding flavor, so we thought we’d reprint it here for easy future reference.
The big question that was on our mind was in regard to dark roasts: Peet started an American tradition back in the 60′s by taking his roasts well into the very dark brown degree and we wondered why. Particularly because, for us, the darker roasts just aren’t as complex flavor-wise, so we were curious about his roasting theory — one that would ultimately be imitated by the founders of Starbucks and eventually influences hundreds of small specialty roasters around the world. It seems that it’s largely due to the fact that, when taken to a darker roast, the oils and sugars caramelize in a manner which imbues the roast with a bittersweet tone — if it’s not taken too far, it will still retain much of its richness and will also feature less caffeine. However, and we think this is where we have often found ourselves, when the beans are taken to a really dark black brown, they’re just charred at that point — dried out little husks with little to no coffee oil or sugar leftover, so very little can be imparted during extraction.
So while we personally prefer something in the medium brown range, we’re glad we now understand why all the dark roast lovers out there are such ardent fans. If you want to learn more about roasting and blending — as well as pretty much anything else to do with coffee — we highly recommend picking up Kenneth Davids’ book.
Right now, however, you can check out his handy reference table after the jump.
We headed out on the road in the beautiful afternoon sunshine yesterday and took a field trip up north to Velton’s roastery, located in Everett, WA. Watch as Velton talks about his history and roasting theory and then takes us through the roasting process from green bean to bag. Yum!
Part One: Velton’s History & Roasting Theory
Part Two: From Green Bean to First Crack
Part Three: From Second Crack to Bag