The Coffee Business and hard water – complementary or worse enemies?

The Coffee Business and hard water – complementary or worse enemies?

What is coffee? Coffee is a beverage brewed from the roasted and ground seeds of the tropical evergreen coffee plant. Coffee is one of the three most popular beverages in the world (alongside tea and water), and it is one of the most profitable international commodities and a life blood for many developing countries and enjoyed by millions worldwide. 

It wasn’t until the late 19th and early 20th century that coffee shops became popular among regular people, as they started to become accessible for those who didn’t work in the government or finance. This rise in popularity was driven somewhat by the fall in wholesale coffee prices towards the end of the 19th century, and most certainly helped by the extremely popular sitcom “Friends” which portrayed the trendy and fun attitude of a group young adults in New York establishing themselves in the world, away from the darker and seedier atmosphere of bars and alcohol.

The first modern percolator incorporating the rising of boiling water through a tube to form a continuous cycle and capable of being heated on a kitchen stove was said to be invented in 1819 by the Parisian tinsmith Joseph-Henry-Marie Laurens. Its principle was then often copied, modified and perfected, especially in Italy where the “to this day” popular Expresso and Cappuccino styles are still enjoyed at pavement “Bars” and Cafés.

So we have established the popularity of coffee, be it from the hands of an expert barista or from the comfort of your own home with “Instant” type ground varieties. But are all coffees the same – of course not there are a variety of different beans, grown in different countries with different climates, all adding to the unique flavors, and made even more diverse by experts who blend the different cultivars of bean, with specific roasting techniques and sometimes even finishing off by cold smoking the beans.

Of course there are other ingredients that go into a perfect cup of coffee which we tend to forget. Probably by volume the biggest constituent of a cup of coffee is water. The water used to brew coffee can influence the end taste. Hard water will generally produce a better tasting coffee compared to soft water, but using hard water in any appliance which heats the water flow would result in the calcium and magnesium coming out of solution and forming scale, not only on the heat exchange surfaces, but also the inner surfaces of the piping and walls of the appliance. So here is the conundrum, do you err on the side of taste or protection of the machine, your asset? Is there a solution for both points? Or should we tackle each problem separately?

For improving the chemical balance of the water, one of the biggest factors is to remove the chlorine which is introduced by the municipal treatment plants to control bacteria, viruses, E-coli, Streptococcus and micro-organisms such as legionaries’ disease without removing healthy minerals (calcium and magnesium) and changing the pH.

 This is important as –

• “According to the Speciality Coffee Association of America, the best pH value would be neutral or rather be more base than acidic as hard water generally produces a better tasting coffee compared with soft water. In fact Roasted coffee beans are packed with compounds like citric acid, lactic acid, and eugenol (a compound that adds a “woodsy” taste) and it was found that magnesium reacts with the eugenol giving the resultant brew an even woodsier taste.”
• The minerals present in hard water (mostly Calcium and Magnesium) are essential for the human body and are some of the most widely used supplements taken by people world-wide.

So to address chemical removal of undesirable chlorine elements present in the water flow, the most common solution would be to use a filtration media such as granular activated charcoal (GAC) or Block Carbon (CTO)

So now, how to address the problem caused by scale without removing the desirable and needed minerals, Calcium and Magnesium? Or can you use other technologies?

We refer to the published article “The pros and cons of water treatment for a perfect cup of coffee” (www.watertechonline.com) where Cang Li, a contributing author, writes about how water can affect the taste and quality of coffee and discusses C Hendon’s (University of Bath, UK) research entitled, “The Role of Dissolved Cations in Coffee Extraction,” on brewing the perfect cup of coffee and explaining why mineral content in water is so important.

“Hard water will generally produce a better tasting coffee compared to soft water; however, hard water will cause scale build-up inside the coffee equipment such as pumps, boilers and valves. This will increase long-term maintenance costs.” 

In order to balance the taste of coffee and maintenance requirements for the coffee equipment, Li in 2014 offers various pros and cons for different water treatment solutions:

• A polyphosphate (siliphos) filter releases polyphosphate to the treated water in order to form a thin, protective layer on the metallic surfaces of the coffee machine. As a result, this technology inhibits scale deposition but this needs to be constantly monitored and treatment adjusted as concentrations above 2-3ppm combined with the duration of exposure these substances can induce chemical burns on the consumer.

• Use distilled water: The distilling process will remove all dissolved solids, including minerals, and will keep all VOC (volatile organic compounds) and any gases in water (such as chlorine if distilled from the tap). Since no minerals are in the water, this leads to under-extraction of coffee aroma compounds. As a result, the brewed coffee is flat. However, using distilled water will protect the equipment without scale out.
• Use Reverse osmosis (RO) water: RO-treated water is close to distilled water and basically is a pure and corrosive form. There are no minerals, causing the coffee to taste flat. Although RO water can prevent scale, it will rust the equipment due to its aggressiveness. Since TDS is very low, this may cause the equipment sensor to stop functioning. A blended RO system has a built-in, by-pass tubing and a valve to mix incoming water and treated water, as well as provides a mechanism for the customers to dial in the precise Total Dissolved Solids (TDS) level to bring some hardness back and to make water less corrosive. Thus, if the cation concentration is right, blending RO water will make good coffee. However this operation need constant checking and maintaining as inflow concentrations will vary from day to day. It also rejects 80% of the water that it eventually filters and is therefore environmentally expensive.
• Softened water: Softening uses ion exchange technology to take out calcium and magnesium ions and introduce sodium ions into treated water. Therefore, softened water causes a flat taste for brewed coffee. A water softener itself will not remove chlorine and/or chloramine from water. Rather, chlorine and chloramine damages the resin beads due to its oxidation power. Softened water will protect the equipment from scale but as it is acidic in nature and it will increase the risk of both chemical and electrolytic corrosion to the machine.

But technology has advanced over the last 10 years, so is there a mechanism that will allow us the best of both worlds? – good tasting coffee combined with the means to protect your coffee machine from scale encrustation and chemical/electrolytic corrosion while not removing healthy minerals?

Today the Modulating Electronic Impulse Anti-scale systems modify the crystalline structure of calcium and magnesium ions from a complex “sticky” three dimensional snowflake configuration which through electrical attraction bind together into a simple cylindrical mono-crystal with positive/negative ends that can only form strings and therefore not cluster together to form encrustations. 

This ionic modification operates in water with maximum temperature peaks of up to 95°C and lasts for up to 2 days in cold water, up to 7 days in warm water (over 30°C) and for a linear distance of 2000m of pipe work before the effect starts to degrade. (Note, there is a 20% engineering tolerance built into the products so these figures are conservative).

This Impulse Technology System has the following advantages

• Stops the initial / further build-up of scale on the pipe work and in appliances
• The carbonic acid produced during the electrophoresis phase dissolves the existing scale in your system
• Produces a protective metal-carbonate layer on the exposed metallic surfaces to reduce corrosion and pitting on metallic piping and fittings.
• It can be utilised on any piping material
• Does not remove beneficial minerals from the water supply nor replace them with undesirable salts or chemicals
• It does not need to be cut into the piping system on installation as the control units are attached to the physical piping and the transfer bands are wrapped outside the piping. As well as being a DIY installation it is also considered a switch on and forget system and is maintenance free.  It requires a normal electrical connection (240v) with very low wattage (2.25 – 3.25 watt), – with minor costs to the consumer 

The Electronic Impulse Technology works as a three tier system to –

a) To stop new scale encrustations

b) To break down existing encrustations

c) To protect the pipework and fittings.

These systems do not employ magnetism, any additives or chemicals (such as salt in ion exchange systems) and leaves the healthy minerals Calcium and Magnesium in the water. Also it does not “soften” the water, only stops the formation of scale encrustations. This means that as well as being healthier, the water is also not as corrosive as soft water (which is acidic), therefore giving double protection to your appliances and pipework.

Electronic Impulse Technology  stops scaling in pipes and appliances

Without the Electronic Impulse Technology treatment, scale particles in the water form “sticky” crystals that join together to build solid deposits. The Electronic Impulse Technology modifies the crystallization of the calcium and magnesium using the natural process of electrophoreses. The crystals become smoother and rod shaped (mono-crystal) which can only attach end to end forming string and can no longer form encrustations. The longer rod shaped crystals that are created, the stronger the positive effect of scale prevention. Scale is now washed away in the water flow as a microscopic powder.

Electronic Impulse Technology gently sanitizes the piping system

The Electronic Impulse treatment breaks the Calcium hydrogen carbonate into its separate elements (electrophoresis) and in doing so increases the availability of carbonic acid thereby enhancing the natural balance between the scaling process and natural resolving process. The resulting mono crystals can no longer form encrustations so the scaling build-up process is reduced. The natural scale resolving process now needs only to deal with the existing deposits and can effectively combat them. The natural surplus of carbonic acid caused by the electrophoresis effect dissolves the scale from the laid down deposits. Gradually and carefully the deposits in the pipes are dissolved and flushed away.  With the scale, the existing rust build-up is converted back into solution and as the encrustations are broken down, the bacteria breeding grounds disappear which greatly reduces and eventually removes that contamination threat.

Protection against rust damage and perforation

Copper and/or iron oxidization occurs in all metal pipes, fittings and appliances through contact with hard water. These oxides seriously affect the surfaces and often lead to corrosion.

The electrophoresis effect caused by the Electronic Impulse Technology generates a protective metal carbonate layer on the exposed metal surfaces against electrolytic and chemical corrosion.

The chemical reaction for the effect of the electronic impulses with a hard (calcium rich) water supply is as follows:

Electrophoresis effect to dissolve existing scale encrustations via the production of carbonic acid

The Electronic Impulse Systems are calibrated to work on pipe sizes from 40mm/1 ½” (or below) with a treated flow of 1360-3000ltr per hour up to 1000mm/40” with an unlimited treatment flow rate and the systems are suitable for all piping materials (iron, copper, stainless steel, plastic, PVC, PE-X and composite) and can treat water with a measured hardness of up to 900ppm/50°dH

Other important factors when looking at anti-scale systems

• Flow rate – as scale builds up in the piping system it reduces the bore of the pipework, allowing less water to physically pass through it and reducing the water available at the end draw off points
• Pressure – as scale builds up in the piping system it would (due to more scale dropping out of solution in hot water due to turbulence) create more encrustations in the hot water pipes than in the cold water pipes and these obstructions would adversely affect the balanced pressure (previously balanced by the PRV) required by ceramic disc mixers etc.,
• Heating efficiency –
  1. On heat exchange surfaces – 2mm build-up can result in a 15% decrease in efficiency
  2. On solar systems – 1mm build-up on heat exchange nubs results in up to 40% decrease in efficiency
  3. Inside pipe surfaces – 1mm build-up can result in a 10% decrease in efficiency due to the scale absorbing heat energy from the water as it passes over it.

• Electrolytic and chemical corrosion
  
  1. When water comes into contact with most metals, oxidisation causes the exposed metallic surfaces to degrade (i.e. iron plus water leads to rust because of the oxygen content in the water) this weakens the material and could potentially lead to failure
  
  2. The resultant direct cost of either repairing or replacing the network can be significant. Also to be kept in mind is the resultant costs suffered by damage due to water damage etc.
• The decreased working life of appliances, machinery, pipework, fixtures and fittings caused by scale build-ups, as well as the costs of early replacement of affected items, downtime for industries and availability factors in the hospitality business

• Health issues –
  1. Although scale encrustations appear to be smooth they are actually microscopically honeycombed which makes them ideal breeding areas for bacteria, viruses and pseudomonas (such as Legionnaires disease) and other micro-organisms.
  2. Although most scale appears red, actual scale is a creamy white. The red colour comes from iron in the water which is absorbed into the encrustations. This absorbed iron can cause the formation of iron bacteria which while posing no threat to human health can lead to bad odours and staining.

As stated the Electronic Impulse Technology system of anti-scale treatment does have certain limits to its operation which must be brought to your attention

1. Ionic modification lasts up to 2 days in cold water before it starts to degrade
2. Ionic modification lasts up to 7 days in warm water (over 30°C) before it starts to degrade
3. Ionic modification lasts for a travelled linear distance of up to 2000m before it starts to degrade (the more bends and junctions in the pipe run, the longer the modification lasts)
4. If the iron (Fe) content of your source water exceeds 1ppm (maximum reading of 0.3ppm is applied internationally for drinking water) it is advised to install an iron removal filter prior the installation of the anti-scale system
5. If the manganese (Mn) content of your source water exceeds 0.1ppm (maximum reading of between 0.1ppm and 0.05ppm is applied internationally for drinking water) it is advised to install an specialised filter to remove the manganese prior the installation of the anti-scale system

We also urge to visit our website www.amanzirms.co.za/cwt-technology where you will find the technology behind the systems explained in greater depth.