Espresso: What you need and need to know. Part Two:Grinder

    The grind and grinder. The grind is very important, it can be the difference in ok espresso and great espresso. Why is that you ask? Well let me educate you on that. The reason the grind is so crucial for great espresso is, there needs to be even and thorough extraction of the puck. So what is the difference between a bad grind and a good grind? Consistency…. that’s the key, that is what you need for a good grind. Every part of the ground coffee needs to be the same, you don’t want large pieces of coffee chunks and likewise you don’t want coffee dust mixed with your ground coffee. Why not? Well if you set your grind size to say “3” but you get some dust say  “½” and you get boulders say “5” you are not getting an even grind. That uneven grind will lead to an uneven extraction of the puck. If the grind is uneven the dust will over extract and be sour, while the boulders are blocking even water flow causing an under extraction. So what is the point of setting your grinder to”3“ when you are getting an inconsistent grind? “Well, there isn’t”. You want to set it to a point and you don’t want it to deviate from that point.
    So what is the solution? A good grinder that gives a consistent grind. Ok then what makes a good grinder? Well, a good grinder always uses burrs not blades, grinders that use blades are by no means good for coffee(however they can make a good spice grinder). With burr grinders there are two types of burrs used, flat burr and conical burr. Which one is better? Better, I could not say definitively, however I will say that I prefer a flat burr set. To me, you get a more consistent grind. Though I know some prefer conical, I don’t.-I have owned both and still like flat burr grinders. There are two main  types of materials used for burrs, they are ceramic and steel, usually stainless. The most prevalent type is stainless steel but there are some ceramic burr grinders, like the Baratza Vario Grinder. I have also seen Titanium burrs, though not many grinders use them and whether they are needed or not is something I couldn’t tell you, as I have never owned a grinder that has titanium burs. Does what the burrs are made of matter? Yes and no, you wouldn’t want burs made of aluminum, (too soft) they need to be strong enough to crush the coffee and hold a sharp edge, aluminum does not fit the bill. So, a grinder in theory could use stone burs if you don’t mind them wearing out quickly. Stainless steal or ceramic is the best bet.
     The short of how burrs work. This applies to both conical and flat burrs. Burrs function in a set of two individual burrs, one upper and one lower. The upper burr is stationary and is the one that is used to control the coarseness of the grind by being lowered down on to the lower burr. The lower burr is the one that is attached to the drive of the motor and is the one spinning which moves the coffee through the set. Together they will crush the bean between themselves.
    The next thing you need to know about is the doser. There are two choices, doser or doserless. A little bit of info, a doser is a chamber attached to the grinder. The coffee is ground into it, then the coffee is dosed into your portafilter basket by the flicking of a lever which drops a pre portioned amount of coffee. The draw back of having a doser is that you have to fill it to get it to work right, which means that the ground coffee that you don’t use will go stale. Unless you are making a lot of espresso in one hit, these are best left to the coffee shops (there are some dosers that do not need a lot of coffee in the chamber to work right but they still will leave some stale coffee in the chamber to fowl your next shot later on). Then there are doserless ones, which is what I have. A doserless grinder grinds straight into your portafilter basket through a shoot, this is the best for home espresso, in my not so humble opinion. Because there are no grounds sitting around to go stale and there is less wasted coffee. One downside of a doserless grinder is that you have to watch to make sure it doesn’t over flow and you usually have to hold the portafilter at the grinder. Now with either a doser or doserless grinder there may be a portafilter holder, this a nice addition but is not a requirement. A portafilter holder does exactly what the name says, it holds your portafilter during the grinding so you don’t have to.
    Next is Motor Speed, fast is not a good thing. Here's why, if the burrs are spinning to fast, the speed will create more friction . The friction will create heat and this is never good because the heat will damage the coffee. Now, a lower speed motor doesn’t mean that it cannot grind a lot of coffee in a short amount of time, that is more a case of torque and the size of the burrs and not the speed of the motor. Just be sure the rpm’s don’t exceed around 1600.
    The next thing is adjustment of the grind. There are two types of adjustment, stepped and stepless usually a worm gear. I will not get into this to much however, stepless is better for espresso because there is more room to dial in your grind, which is needed for getting that perfect shot. The one downside to me, is that a stepless grinder is harder to switch between espresso and say Vacpot or French press, hard but not impossible it just takes some time to get there.
     Throughput is something that should be considered. Throughput is the amount of coffee placed in to the grinder and received after grinding. It’s important because if you put in 30g of whole coffee you should get 30g of ground coffee, not 28g or 29g. Not all grinders will say what throughput they have, so do some looking.
    Finally, if you find a grinder you like, look for someone that has the grinder on a forum like coffeegeek.com or homebarista.com Ask some questions before you buy the grinder, like how long they have had it, how much they paid and, well, any thing that comes to your mind. Anything more I should know? Well everything else is just not as important, like how much the hopper holds or the color or timers, all should be considered, but are not needed for great espresso.
    One last thing on a grinder, if you are buying your first burr grinder with your espresso machine. The grinder should be 50 percent of your total budget, up until the 50 percent is over $700 at that point it is just a case of diminishing returns. I would suggest that you buy the best possible burr grinder, and if necessary wait on the espresso machine and use a Vacpot or a French press, until you have enough to buy the espresso machine you want.


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Espresso: What you need and need to know. Part Two:Grinder by Noah Brewer is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.