CoffeeForums Coffee Facts

Q: Crema is apparently the layer of light bubbly stuff that forms on top of good coffee immediately after hot water is poured into the grounds. What is in crema that makes it a sign of good coffee? What does it consist of and why is that good?

A: It's not. Crema is formed only when water is forced under pressure through finely ground coffee in an espresso machine. It is neither light nor bubbly, but fairly dark and creamy as the name implies. A coffee that will produce a lot a crema will also produce some of the foam you describe, but they are not the same thing by any stretch. It is an emulsion of the coffee oils with the hot water (in the same way that mayonnaise is an emulsion of eggs and oil). It's good because emulsions have a creamy taste. They stick to the tongue without feeling oily. Raw eggs and vegetable oil are both unpleasant to taste straight, but when emulsified together, they form a tasty mayo. Crema (unless produced by "artificial" means in a "crema enhancer" is both a sign that proper extraction has been achieved (unless all factors - coffee freshness, grind, tamp, water temperature and pressure - are close to optimal you won't get significant crema, which is what makes it so elusive) and a tasty substance in itself. Well ah'll be! Never have been an espresso drinker so this is news to me. Question: Can I get crema out of a cappuccino maker if I use a light roasted coffee? Does the darkness of the roast have anything to do with it? Crema results from the process of espresso extraction, which is accomplished by using a machine that forces water through under pressure (said the scientifically challenged user - me). A machine that relies on steam instead of a good pump to create the pressure is often labeled an espresso or a cappuccino maker, but a "steam toy" doesn't produce what most people here would call espresso. Even a drip machine that cannot make ANY sort of claim to producing espresso, often gets billed as a cappuccino maker. I'll be kind and suggest that the manufacturers are...confused. Cappuccino is just a coffee drink you can make with espresso. You need the espresso first. If you just have a machine that can make coffee and froth milk, that's coffee with frothed milk, which I like, by the way...but cappuccino it ain't. What's going to get you good crema is good brewing and especially good, fresh beans. Lots of machines come with pressurized portafilters (the long armed filter basket holder that gets set under the brew head), and the pressurization "forces" crema to form where it might not, at least to such an extent, otherwise. The general consensus I've read is that the extra "fake" crema comes at the expense of the flavor of the espresso (makes it a little bitter), and that as physical evidence of a good pull, you want to be able to see if you got good crema without the "artificial aids". Personal disclaimer: If you are happy with a steam toy or a pressurized filter or what have you, so be it. Me, I started with a stovetop moka pot, then a steam toy, and I'd probably be well on my way to some espressoholics 12 step program if it wasn't for financial constraints. But just for a couple hundred, I got myself to the point where I have a "real" espresso machine, a grinder that grinds fine enough, and a decent roaster. Less, in a way, because I sold the old stuff on ebay -- you wouldn't believe what people will pay for the used stuff. ;-) And after a year with the pressurized one, my non-pressurized portafilter is in the mail.