Coffee Machine Water Filter

Having spent a lot of money on your coffee machine, the last thing you really want to do is spend more. So when you are offered a water filtration system, and you hear the price, it will be tempting to say "I'll think about it" or simply say "no thanks". That, however, would be a mistake and here are three reasons why.

Coffee is 98.7% water – so what goes in your cup affects the taste
Don't take our word for it that water quality is a major determinant of coffee quality. The Specialty Coffee Association of Europe has produced a report that shows exactly how water that is too hard/too soft or has too little/too much alkalinity, can affect the taste of your coffee. It really is a simple concept if we think that flavours in our coffee, like the chlorogenic acids, are well…. acids… and if your water is highly acidic, then you are compounding acidity. It's why you can love a brand of coffee in one city and find it insipid in another (assuming your barista isn't the major problem!).

Good coffee requires that hardness and alkalinity are within a certain range. This graph shows that for good coffee, hardness must be between 40 and 80ppm and alkalinity mut be between 40 and 100ppm.The graph they published is reproduced to the right and you can see that there is indeed a sweet spot area where coffee will taste its best.This is what you as a barista, café, restaurant, hotel owner or manager of a corporate coffee machine solution, want to ensure your customers and staff are experiencing. Of course for those who own automatic coffee machines or manual espresso coffee machines at home, this is the area you need to ensure exists for your own coffee enjoyment.
A good water filtration system will offer you this. It requires that your water is tested, and that the formula applied to determining just exactly what filter you need, is applied correctly.

Water filters remove impurities
Coffee taste is of course the most critical reason for installing the appropriate water filter system. However, no matter how much you are in the SCAE zone depicted above, if your water is tainted by chlorine or unsafe to drink, you'll still have unhappy customers or for home drinkers, an unsatisfactory coffee experience.
Water filters for coffee machines are therefore designed to remove particulate matter like algae, soil etc and also to remove the chlorine taste and odour. As this happens immediately prior to boiling in your coffee machine, there is no health hazard and in fact only a health benefit because heating water which contains chlorine can lead to the formation of unwanted chlorine chemical by-products.
Good water filters will also remove bacteria and cysts and you may be tempted to say "doesn't that happen when water is boiled so why do I need a water filter for that?" but the truth is that not all water goes to your boiler (and sometimes, boiler temperatures fall below that needed to kill cysts and bacteria). Some water will by-pass the boiler to be used in controlling water temperature or for direct dispensing and this can cause contamination. So it is always better to have the protection of a water filter.

Water filters reduce your maintenance costs
The water you use in your coffee machine will most likely come from a municipal water supply and the water supplied in Cape Town is different in its composition to that supplied in Johannesburg, London, New York or wherever you live.

The main differences are in its pH, total dissolved solids, general hardness and alkalinity levels, but of course, there are also going to be differences in chlorination levels, presence of heavy metals and of course bacteria, cysts and viruses.

The first thing you need to know is the level of each of these and then what you need to do about them. This is where expertise is needed because water chemistry involves a complex interplay between these parameters and selection of the right water filter heavily depends on this understanding.

Without getting into complex chemistry, the most important thing to realise is that your water can range from being corrosive to being scale forming in your equipment. There is absolutely no point in having a water filter that protects your equipment from scale build-up if your water is not scale forming. Makes sense, but unfortunately this is where bad advice can have you spending money to protect your equipment only to have to spend more money getting it fixed!

Water that is corrosive will damage your equipment as it interacts with the metal surfaces in tubing, boilers and brewers. It is not uncommon at all to find boilers that are pitted in areas where water is measured as corrosive. At the other end of the scale, water that is scale forming will deposit scale on metal surfaces that can block tubes and coat your heating surfaces with calcium carbonate, an excellent insulator. Your heating capacity and water temperature will decline over time and your electricity consumption will increase.

The end result is more cost. You'll have to replace pitted boilers, and your scale filled boiler will need to be acid washed to restore its surface back to a normal condition. These are not insignificant maintenance costs and will both impact your bottom line and your coffee quality.

We use the Langelier Saturation Index to calculate just where your water is on this scale that runs from highly corrosive to highly scale-forming and we determine where on that scale your water sits.

Once we know that, we can look at your water as it arrives at room temperature, through what it will do in your boiler at 95 to 100oC and if you have a coffee machine that makes steam, what it will look like at 125oC. Armed with that knowledge, we can recommend the correct filter (the FX-10 for softer water and the VH-IEN range for harder water) and when you are using a filter to protect you from scale-formation, we can set the bypass water flow to maximise the life of your filter.

Our suggestion
When investing in a coffee machine that will last many years if well maintained, there is little point skimping on the installation of the most appropriate water filtration system for your water quality.
The economics are quite simple. If a water filter can handle 20 000 litres and it costs you R 2000, then you are looking at 10c a litre or a mere 2-3c for each cup of coffee. Work that against a cost of replacing your boiler or the down time and technician cost for a boiler descale.