As coffee aficionados, you’re no doubt aware that espresso is made up of 90% water, meaning that the quality of the water you use is of critical importance, as water quality has a big impact on the taste of your espresso. However, you may not have considered the role that good quality water plays in aiding the longevity of your espresso machine.
For some time, the guys in 5 Senses’ Technical Department have been investigating water systems to find out how best to provide a high quality water supply to your machine. The answer, they believe, lies in Reverse Osmosis.
To understand how Reverse Osmosis works, you need to know a bit about Australia’s water supply. Our water is a mixture of dam (rain) water and ground water. The percentage of ground water varies from State to State, reaching up to 60% in Western Australia and South Australia. The inclusion of such a large amount of ground water means that our water contains high levels of minerals such as calcium, magnesium and chlorides.
High levels of minerals in the water supply can cause problems for your espresso machine. Calcium and magnesium create a deposit called Lime Scale which can coat interior surfaces of your machine, eventually leading to blocked pipes, restricting the operation of precision water control devices and causing valves to leak. Lime Scale can also coat heating elements, making them considerably less efficient, and thus more costly to run.
In addition, chlorides, which are found in varying amounts in Australia’s water supply (again, they are especially high in Western Australia and South Australia), are very corrosive to metal components, particularly the 304L grade stainless steel used in high-end espresso machines. This is exacerbated when the water is under high pressure and at a high temperature – both of which apply to the water in your espresso machine.
While standard filtration systems can remove particles and some chemicals, such as chlorine, they leave behind varying levels of dissolved minerals, which can compromise the quality and taste of your espresso and cause the aforementioned machine problems.
Reverse Osmosis is a process which purifies water by using pressure to force pre-filtered and chlorine-free water through a microscopically fine membrane. This membrane prevents unwanted particles and minerals from passing through, but allows ‘pure’ water to pass through freely.
After months of testing and evaluating water filtration systems, the 5 Senses techs believe they have discovered the best system on the market. The Aqualife AquaCaffe ® is a five stage Reverse Osmosis system which utilises advanced technology, and is specifically designed for use with espresso machines. It was certainly the most effective system in removing a very high percentage of unwanted dissolved minerals, chemicals and organic matter.
Blind cupping sessions confirmed that espresso produced with the Aqualife AquaCaffe ® system tastes superior to that produced with other systems or using standard filtered water. The RO-brewed espresso was the unanimous favourite. Jay described the difference between them as ‘akin to the difference between drinking wine out of a fine crystal glass as opposed to a beer mug. While the flavours in the cup don’t change, they have a refined clarity that consistently stood out over that of the normal filtered tap water.’ After many blind cuppings with four different cuppers, the coffee prepared using water filtered through the Aqualife AquaCaffe ® came out on top every time.
If you are interested in finding out more about Reverse Osmosis for your café, please contact Richard Muhl, 5 Senses’ Technical Support Manager, at our Western Australian roastery on (08) 9528 6200.
