One of the most frequent questions I get asked is in regard to coffee grinders.
If you enjoy fresh coffee made at home, then the first choice is usually a cafetiere which is relatively cheap and gives you the satisfaction of brewing your own coffee, the smell, getting the right amount, the right timing, and the excitement of maybe brewing the perfect cup of coffee ( that last bit might just be me though). In coffee world, cafetieres are referred to as a full immersion method. Other stops along the way are the various filter methods, aeropress types, and full on espresso machines. Even if you go straight for a bean to cup machine, it is useful to understand the mechanics of grinding the beans.
I will cover grind size and its importance more fully in another ‘musing’
Back to basics, the biggest step to improving your coffee ‘experience’ is to grind the beans just before you use them. Go into any coffee shop and you will find there is a grinder right next to the coffee machine. This is no accident! Top baristas in competitions will only tolerate a maximum of 20 seconds once the beans have been ground before creating their coffee for judging. ( if you enjoy watching paint dry, these championships are for you ).
Anyway, back to reality, there are lots of domestic grinders to choose from.
The first type are the ‘knife’ type, sometimes sold as spice grinders. The attraction is that they are very cheap (from around £5 upwards). A dedicated coffee grinder type will purposely only have a small capacity, and usually have a pulse type switch, to avoid overgrinding. Apart from their price, other advantages are that they are quick, easy to clean and don’t take up much room on the worksurface. Their disadvantages are that you don't really have much control on how fine or coarse the ground coffee turns out. This is important because if you overgrind the beans you will have lots of sludge in the bottom of your cup, whereas under grinding will result in a ‘thin’ coffee with little taste. The major disadvantage in my view is that they always heat the grinds up as the blades whizz through the same beans time and time again. This is bad because it drives off the lovely aromatic bits of the coffee. (you want the flavour in the cup rather than in your nose!).
The next level, admittedly at a higher price, are burr type grinders. These work along the lines of a small millwheel. There are two horizontal grinding discs, facing each other and the beans feed in from the centre. As they spin towards the outside they are ground by the wheels and collected in a hopper beneath. They have the advantage of being able to grind different particle sizes so you can tailor the right size for your brewing method. At least three manufacturers offer an entry level burr grinder at around £40. These are Delonghi, Krups and Klarstein. They all boast variable grind settings, but in my experience ( I have actually bought several of each of them ) whilst they all grind a size which is perfect for a cafetiere, they may, or may not, be able to grind fine enough for an espresso machine. Filter coffee is between the two and is almost always achievable too. There is generally nothing wrong with their longevity, for instance I used a Delonghi.for five years commercially for decaf beans, it was one of the ones that did achieve the espresso grind of course. They also differ with some of the internal materials, and size of motor, but they all work well, and you should be pleased with whichever choice you make. If you have preferences as to where they are made, both Delonghi and Krups are from the far east, whilst the Klarstein is actually made in Germany. So, an excellent choice and not too expensive.
Up one level to a higher spec of grinder will cost around £70. There is lots more choice at this level, and probably the highest number of domestic grinders are in this bracket. Most of them work on the same principle of two grinding wheels, one stationary, the other spinning. Apart from the higher price, they will also take a larger space on your worktop. They do offer stronger motors and a ‘quicker’ grind. There is a holy grail of achieving ground coffee by not heating the beans in the process. Two main schools are either 1: a faster spin, so although more heat is generated, the process takes a shorter time thus not heating the beans. Or 2; a more powerful motor to grind slowly, thus not generating too much heat in the first place. As far as producing a fine enough grind for espresso is concerned, these are almost certain to perform well, but there may be a few rogues amongst them. At this level, if they don’t, I would return them.
As if it weren’t confusing enough, there is a third type of grinder which emerges at this level, and competes with flat burrs right up to full professional level (£2,000 ish). These are called conical burrs. Imagine a funnel with a cone shaped grinder inside it. The beans fall into the funnel and get progressively cut and cut again until the are small enough to fall out of the bottom of the funnel. Mechanically it needs less power because the motor doesn't have to drive a flat wheel round, so can run faster. The beans are actually ground more slowly and therefore don’t overheat. So goes the argument. I do have experience of the Dualit version, and I am very pleased with it as one of its main benefits is that it is easy to clean out. I bought it (well another five of them actually). I use it commercially in the coffee pod for decaf beans, and also in the roastery for grinding small amounts of different coffees for tasting sessions. It does have a few drawbacks in that it has to be empty before removing the hopper or all the beans will fall out, and it is easy to change the grind size without meaning to! I have read the reviews on it and they do have a few people saying it can’t achieve an espresso grind, but the five I have bought show no signs. As above, at this price I think I would send it back if it didn’t!
From here on up, you are in high end domestic and borderline commercial. At this level (£150 and above) you are more likely to have done your research and are probably very knowledgeable on the subject anyway. You would also expect good design and performance thrown in for good measure.
Summing up, for a domestic grinder there are three different types, all with their pluses and minuses and price levels. I hope this has helped inform your choice, but remember the most important thing, and the reason why you should grind your own beans, only use the hopper to catch the beans, not to keep them for later! In other words, only grind just enough beans for immediate use. If I have any ground coffee hanging about for more than an hour in a hopper I throw it out, but then it is my reputation at stake!