Top 5 Coffee Grinder Tips – Which is Best and the Differences?
Which coffee grinder is the best and the differences between them – Top 5 tips and tricks
During my recent visit to the 2014 London Coffee Festival I had several very interesting conversations with Baristas about the kit they used and the coffees they enjoyed making. Before long, talk inevitably turned to which coffee grinders are the best? A piece of kit that that is often neglected. Lacking the glamour of a shiny new espresso machine, and usually somewhat of an afterthought when budgeting for a café setup, the coffee grinder is nevertheless a vital part of the espresso making process. There have been huge strides forward in the last ten years when it comes to espresso machines, but the next generation of grinders has been a little slower to come to market. Though the debate at the festival was fierce when it came to brands and models, the message was clear – the grinder is THE key to good espresso!
With this in mind I have put together a summary of the many options available, the differences between coffee grinder blades, on-demand vs manual grinders and some tips on how to get the best out of them.
Blade Grinder or Burr Grinder?
There are two main types of coffee grinder, burr grinders and blade grinders. Blade grinders work by smashing the beans up with a blunt rotating blade. The longer you grind, the finer the resulting grounds. This method is normally used by cheaper domestic models, and is of no use whatsoever for making espresso as the resulting particles are inconsistent in size, and the end result is often unpredictable.
Burr grinders have two toothed discs that the coffee beans pass through, where they are milled into a desired size by changing the size of the gap between the two discs or “burrs”. This will give you the accurate and predictable particle size that is required for making espresso.
Coffee grinder blade type – Conical or Flat?
The two types of burrs available are called “flat” or “conical”. They have varying pros and cons but can both obtain excellent results. It is often said that conical burr grinders have the edge as their slower rotating speed while grinding causes them to heat up less. This is desirable as hot blades will dry out or even scorch coffee grounds which will make espresso extraction unpredictable and even bitter tasting. However, it is also true that due to the larger quantity of metal in a conical burr, once they get hot they take longer to cool down. I don’t think there is too much to choose between them, but the conical burr does tends to produce more “fines” than a flat burr. These micro particles of coffee, though adding body to espresso, can also increase the perceived bitterness so I would say that unless you find that in a side by side comparison, a conical burr grinder tastes better with your coffee, the flat burred grinder is the one to plump for.
Manual versus “on demand” coffee grinders?
The traditional “manual” grinder has a chamber to hold the ground coffee, which is then dispensed into the group handle by pulling a lever on the side of the machine. These can often be set up so that each pull dispenses a single espresso worth of coffee. If you have a model that can vary the amount dispensed with each pull, and are prepared to set them up properly, then these grinders are a solid choice. They are relatively affordable and quick to dose, which is desirable in busy environments. However, if ground coffee is allowed to sit in the dosing chamber for more than a few minutes the risk of staling is high. To avoid this, grinding for each order and using the “fill and level” method of dosing is advisable.
The difference with on demand grinders is that they have no dosing chamber. They grind coffee directly into the group handle on a timer so that exact dosing can be attained. This makes them more accurate than the manual grinder, which helps baristas pull consistent shots. The lack of a chamber in which coffee can stale means that fresh coffee is always used, another big plus. The only real downside apart from the price (about twice as much) is that they can be a little slower. That said, when it comes to espresso, consistency is key and I would choose an on demand every time (if budget allowed!).
Fix up, look sharp! When should you replace your blades?
Whether conical or flat, manual or on demand, those burrs need to be sharp and stay sharp. In order to produce the even particle size we need for espresso, the coffee bean needs to be sheared accurately and finely into consistent grounds. Over time, blunted blades mean that the grinder will eventually stop producing the fines I mentioned earlier, with a marked detriment to cup quality.
You will also need to set the grinder blades increasingly close together to achieve the desired fineness, which can cause excessive heating of the blades and expose the grinder motor to potentially damaging levels of stress. To avoid this, it is very important to change steel burrs for every 500kg of coffee they process (about once a year for the average café). The cost is around £50 and well worth every penny. This service can be provided by a coffee supplier such as Refreshment Systems, so make sure to replace your coffee grinder blades if you think your grinder needs a bit of T.L.C.
Titanium edged tungsten blades are worth looking into, even though they are more expensive (around £150 a pair). They stay sharp for 2000kg or more and apart from saving the hassle of regular burr changes, they can reduce wear and tear on your grinder. Whichever you choose, keep track of their use and keep them sharp!
Coffee Grinders: buy right, buy once
Setting up a café is expensive and a grinder may easily slip down the list of priorities. The fact that it is often bundled with an espresso machine means that people are often not clear how much they have paid for it or even what model it is. The problem is that a cheap grinder will have a limited life and will struggle to produce consistent grinds in a busy environment. Setting and managing grind size is perhaps the most important barista skill as it produces the raw ingredient from which espresso is made.
No matter how fancy the espresso machine, or how much skill and care the barista puts into the extraction, poor grind will make poor coffee. It’s like buying a Ferrari, sticking Lewis Hamiliton in the seat and then filling it full of chip fat instead of four star. You might get round the track a few times but you’re never going to win Le Mans!