The quality of
drinking water in the UK is specified in the European Union’s Drinking Water
Directive (98/83/EC) and in England and Wales is regulated by the Drinking
Water Inspectorate. The Directive is very specific about microbiological and
chemical composition but interestingly states that taste and odour should be
‘acceptable to consumers’.
From the coffee
maker’s perspective there are two reasons to treat water before it enters a
coffee machine – to improve the taste of the final drink and increase the
reliability of the coffee machine by reducing scale build up.
There is no
doubt that the composition of water will affect the taste of coffee. The extent
to which various dissolved solids and their concentration exactly play out
against the different taste sensations has always caused some debate. The water
specifications required to give the expected taste for any given coffee is
probably best left to the coffee roaster. Where Cimbali can offer some insight
and advice is how to protect a coffee machine from scale build up.
Coffee machines
with steam boilers are inherently vulnerable to scale build up because the high
temperatures encourage the deposit of scale and then this scale can lodge in
various components causing blockages. Descaling machines is expensive and often
requires the machine to be taken off site, the boiler treated with acid
descaler and the replacement of many parts such as the heating element and
level probes.
There are a
number of water treatment systems on the market, principally: cartridge
systems, sodium water softeners and Reverse Osmosis systems. Whichever system
you choose there will be a number of factors to consider and weigh against each
other – cost, effectiveness, corrosiveness of output water, waste water, taste,
capacity and environmental considerations. At Cimbali we favour the use of
sodium water softeners because we believe they offer the best compromise of all
these considerations.
Whatever system you choose we can share
some of our experiences when maintaining water treatment systems.
•
Capacity. All systems have a
defined maximum capacity and it is important to size them correctly to avoid
running out of treated water or paying too much for an over specified unit. A
double espresso cappuccino uses about 150ml of water which for a busy machine
servicing 200 drinks per day would equate to only 30 litres per day. But be
careful – water usage could 50% higher than this if you take into account water
for Americanos, tea and machine cleaning. We have even found cases where staff
are using the coffee machine hot water to fill buckets for floor cleaning. In
order to know exactly how much water is being dispensed by a coffee machine it
is vital to fit a water meter. We recommend individual water meters for each
machine that are non-resettable and count up because the water usage history is
never lost.
•
Water Hardness. It is
surprising how many people do not test the hardness of the water entering their
coffee machine. There are many regions of the UK that do not have hard water
and if you are happy with the taste and odour of the local supply, save some
money and do not fit a water treatment system.
•
Installation. Often water
treatment systems are located at the back of an under counter cupboard and are
soon are obscured by cleaning materials, paper cups, ingredients and so on. It
then is all too easy to forget about routine exchanges and maintenance.
It is also worth reviewing water
treatment for the whole operation. It makes sense to consolidate the water
supply to all machines that require scale-free water such as dishwashers, steam
ovens and water boilers.
•
Systems. Scheduling service and
maintenance is vital. It is not unusual to service the water treatment system
every 6 months or so. With such a long gap between each visit it can be
difficult to incorporate this in the daily operating routine of a business.
Water treatment should have the same status in the business diary as
significant events like boiler inspections and equipment preventative
maintenance visits. It is all too easy to forget about water treatment service
because the damage being done by scale is unseen until it is too late.
Not a pretty site –
scale build up in a boiler without adequate water treatment.
