Here at Machina, we are self-confessed coffee geeks of the highest order – but obviously we don’t want to bamboozle anyone with nerdy chat or coffee jargon.  So here’s a few FAQs that we hope are of use.


What’s the difference between a heat exchanger (HX) and a dual boiler (DB) espresso machine?
Both can make espresso and steam milk simultaneously. DBs offer additional control over brewing temperature, eliminating some of the guesswork involved in coffee preparation.


What’s the difference between the home espresso machines that cost less than £300 and the ones you sell?
Lots of things! We only sell machines that we know you can make amazing tasting coffee with. Artisan machines from companies like Rocket and Expobar are made of high grade components and are built to last.  Most importantly, these machines are capable of much better temperature stability than cheaper models, which is vital for the perfect shot. 


What are the key factors involved in making amazing espresso?
There are many factors, which is why making espresso is both an art and a science (and can get very nerdy!). The following things need to be considered when making espresso: 

  • The coffee (quality, origin, blend, quality of the roast, and freshness - the coffee needs to have been roasted between 3 and 14 days ago, any older and it will be stale)
  • The grind (a quality espresso grind is fine and even, the coffee needs to be ground just before you pull the shot)
  • The tamp (this must be even and the right pressure needs to be applied to allow the optimum flow of water through the coffee)
  • Accurate temperature control (the shot must be pulled at the right temperature to create a perfect sweet, almost sour taste which is great on it's own or cuts nicely through milk to reveal a complex and balanced flavour profile)
  • Timing the extraction of the shot (it typically takes 25-27 seconds to pull a shot)


What is tamping and is it important?
Tamping is the method use to evenly compress the coffee grounds into the portafilter - and yes, it's another essential part of pulling great espresso.  If the 'puck' of coffee has not been tamped correctly, your espresso may over-extract (meaning it comes out too slowly - which tastes bitter) or under-extract (when it comes out too quickly and taste sour). See also Coffee Geek article on the science of tamping


Why is it important to get the right grinder?
Choosing the right grinder is crucial in achieving perfect espresso or filter coffee. Top quality grinders provide consistency, are easily adjustable, create little waste, and vitally, they can cope with volume. If a grinder can’t cope with the volume of coffee being ground, the burrs get hot.  This heats the coffee and results in bland, flat tasting coffee, because the flavours are being released before the shot is pulled.
See our guide to buying a grinder


I’m interested in filter coffee techniques – what do I need and what should I consider when choosing my kit?
Considering how much coffee you want to brew at any one time will determine the size of the brewer you need. If you only drink one small cup, then look at the Hario V60 01. The V60 02 gives you the option of one small cup/one large cup/two small cups. If you want to brew 500ml-1l at a time, then you'd be best with a 6-Cup Chemex. All of these brew methods work best with a pouring kettle such as the Hario Buono. Once you have chosen a brew method, you will need to select a grinder. See our Grinder Guide for more information. A set of digital scales will help keep things consistent!

For more information on brew techniques including detailed recipes, see the Brew Methods site


Why do brew methods require a special kettle?
You can use a normal domestic kettle when making filter coffee with a V60 or Chemex.  However, the advantage of a special pour over kettle like the Hario Buono is it's narrow spout.  It allows you to pour very accurately which is important in pour over techniques - where the aim is to evenly pour the correct volume of water for the optimum extraction of the coffee. When done correctly, the coffee will taste balanced, not bitter. This technique is normally used for single origin coffees, as it is a gentler way to tease out the full profile of complex flavours, than the high pressures and temperatures used in making espresso.


Should I bother getting my home espresso machine plumbed into the mains water supply?
If you have the facilities and don't plan on taking it on holiday with you, then you may want to consider this. Plumbing in means you don't have to refill the reservoir every other day, and the drip tray drains directly into the mains waste pipe in your house. If you make a lot of coffee then this is a more practical, long-term solution.