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We know that water is one of the most important ingredientsin a cup of coffee. In this booklet we will cover watertreatment for the perfect espresso, water profiling for coffeeprofessionals and how to create the perfect cup of coffee.

Our aim is to give you a clear understanding of water; theissues you need to address, and the options you can considerto ensure the best coffee experience for your customer.

WATER FORCOFFEE LOVERS

1. EVERPURE • WATER FOR COFFEE LOVERS

MAKING WATERWORK FOR YOUBrewed coffee is over 98% water, the remainderbeing compounds that are extracted from thecoffee grounds. The quality of water used forbrewing coffee can have a dramatic effect onthe taste of the finished product and theperformance of your coffee equipment.

We want to identify and highlight the importantobjective and subjective issues that revolve aroundtaste and equipment protection, enabling you tomake informed decisions about your watertreatment options.

We’ll start with an objective summary of waterand how it affects brewing equipment.

Fact: Hard water will form scale inside coffeeequipment, reducing equipment efficiency, causingcostly failures and in a commercial enterpriseultimately loss of revenue.

But it’s not just Hard water that can causeequipment damage. Water is considered to be the“universal solvent”. the purer the water, the morecapable it is of damaging equipment by promotingcorrosion. this is also true for water with a naturalor artificially low pH. additionally, many watersources contain mineral salts that can be corrosiveas well as scale forming.

TdS. ThE CATIONS

Calcium & MagnesiumOften called the hardness minerals. calcium and less soMagnesium are generally the most abundant of the cationminerals in water. calcium can form insoluble salts whichcreate the “scale” issues affecting equipment performance.

Whilst it is accepted that a good cup of coffee needs some ofthese hardness minerals, there is evidence to suggest thatcalcium is preferable to magnesium, further backed up byreferences from the beer industry that magnesium salts canadd an unwanted astringent bitterness.

Sodium & PotassiumSodium is usually more abundant in water than potassium.at low levels they can add a welcoming sweetness to thebeverage, whilst at high levels sodium salts can taste… salty.

Sodium salts are usually highly soluble so unlike calciumwon’t cause scale issues, but it is believed that Sodiumchloride can swell coffee grounds effecting extraction timesand rates.

Due to its links with potential health issues, the amount ofSodium allowed in drinking water is limited to 200 mg/litre.

the Scaa recommendations are for sodium content ideallyto be around 10 mg/litre.

Iron & CopperEven in relatively small amounts metals such as Iron andcopper add a metallic taste to a beverage.

Both can be present in the water supply but increased copperlevels can occur due to corrosion in building pipework and / orbrewing equipment.

TdS. ThE ANIONS

Carbonates, Bicarbonates and hydroxidesalso known as the alkalinity ions. carbonates form salts withinsoluble hardness metals, causing scaling of equipment.

as alkalines they also have a great effect on the pH of thewater.

the Scaa recommends a desired alkalinity level around 40mg/litre as calciumcarbonate (cacO3).

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WATER; WhAT IS IT ANdhOW dOES IT RELATETO COFFEE ANdCOFFEE EqUIPMENT?

It is well documented that pure wateris a chemical substance with formulaH2O: one molecule of water has twohydrogen atoms covalently bonded toa single oxygen atom, and in its pureststate has a pH of 7 or neutral. Water isvery rarely found in its pure state; sowhat’s in your tap water will impactthe coffee you brew and your coffeeequipment. Some of the relevantinformation has already been widelydebated within the barista community,other issues have not previouslyreceived as much attention. We willcover the key topics and theirinfluence on coffee. We can also drawon existing knowledge from the widerbeverage and brewing industry wherewater chemistry has long beenunderstood.

TOTAL dISSOLVEd SOLIdS

• total Dissolved Solids (oftenabbreviated tDS) is basicallyanything in the water that isn’tHydrogen (H) or Oxygen (O). thesecan be dissolved or suspended(colloidal) particles. In general tDSare not considered to be associatedwith health issues, high tDS waterwould normally indicate a highwater hardness.

• Minerals dissolved in water can besplit into two categories, positivelycharged ions (cations) andnegatively charged ions (anions).

• the Scaa recommends that tDSlevels are between 75 ppm and 250ppm so as not to adversely affectcoffee extraction and taste.

ChloridesSodium chlorides can give a salty taste to coffee.chlorides are also the nemesis of Stainless Steel,and at high levels can break down the protectivecoating causing pitting corrosion.

the effects of corrosion on stainless steel aresubject to many variables, so it is always best tocheck with your equipment manufacturer fortheir recommended chloride limits. Somemanufacturers suggest a threshold of 30 mg/litresothers quote limits as high as 100 mg/litres.

Sulphatescalcium Sulphate in water will cause a hardwhite scale. Fortunately calcium Sulphate isslightly more soluble than calcium carbonate andSulphate levels are usually far lower than thoseof carbonates, so Sulphate scale is not generallya problem.

phpH is the measure of acidity or alkalinity. If there aremore H’s than OH’s than carbonates the water willbe acidic and vice versa the water will be alkaline.

that’s not the end of the story. Water likes todissolve gases such as carbon Dioxide (cO2) whichwould create mild carbonic acid. High levels ofdissolved carbon Dioxide will make the watermore acidic.

pH 7 is neutral, Scaa recommendations arethat levels of between pH 6.5 and pH 7.5 arebest for coffee.

hARdNESS

the definition of total Hardness is the sum of thecalcium and Magnesium ions in the water. Inreality most water hardness is predominatelycalcium hardness.

certain salts of these metals are insoluble and themain cause of limescale. Hardness also affects therate of extraction of brewed coffee. to achieve abalanced brew the Scaa recommend a hardness ofbetween 17 mg/litre and 85 mg/litre whenmeasured as cacO3.

tOtal HarDnESS IS MaDE up OF tWO cOMpOnEntS:

Permanent hardness is the amount of hardnessminerals that can’t be removed through the boilingof water.

Temporary hardness also known as carbonateHardness, is the measure of hardness mineralsthat can be removed by boiling. this will bepredominately calcium carbonate.

dISINFECTANTS

With the noticeable exception of Denmark, themunicipal water sources in most countries aretreated with disinfectant to prevent contaminationfrom bacteria and viruses which otherwise couldbe harmful to health.

chlorine is the most commonly used disinfectantbut in the uSa, uK, Sweden and Finland there is agrowing practice to use chloramine, a compoundof chlorine and ammonia.

chlorine and chloramine not only impair the coffeetaste by oxidizing essential oils, but can also becorrosive to metal parts and damaging to “O” ringsand seals.

For good coffee chlorine and chloramine should beremoved from the water along with any other offtastes and odours.

dIRT PARTICLES

Even though you might not be able to see them,water contains lots of small dirt particles. theseparticles can act like sandpaper and be damagingto equipment valves and seals. the particles canalso accumulate to block the small valve openingsin modern brewing equipment.

3. EVERPURE • WATER FOR COFFEE LOVERS

WATER TREATMENT TEChNOLOGIES

now you understand what’s in your water, wehave to look at the common technologies usedto treat it.

these technologies may be used individually orcombined within a single system or unit.

Sediment FilterIn its most basic form a sediment filter is ascreen to filter out dirt particles. at the otherend of the spectrum it can be a membrane filtercapable of removing viruses and bacteria fromthe water. choosing a filter with a micron rating≤ 5.0 microns should ensure that your water isfree from damaging dirt particles.

nOtE: Some filters employ a blending bypass.Don’t treat the bypass water for sedimentremoval.

Carbon Adsorption carbon filters are extremely efficient atremoving chlorine, off tastes and odours fromthe water supply. carbon can be incorporatedinto a filter in a granular form or in a more solidform such as a carbon block also incorporatingsediment reduction capabilities.

nOtE: Some filters employ a blending bypass.Don’t treat the bypass water for chlorinereduction.

Whilst carbon is efficient at removing chlorinemany carbon filters are not efficient at removingchloramines. Should you be in an area wherechloramine is a problem it may require investingin a filter containing specialized carbon filtrationthat will remove chloramines.

98% WATER

2% COFFEE

SOFTENING TEChNOLOGIES

STRONGLY ACIdIC CATION RESINSSalt Softenersthe vessels of these water treatment units containsmall plastic beads (resin) charged with sodiumions. In all water conditions the resin will exchangetheir sodium ions for calcium and magnesium ionsin the water, effectively removing hardness fromthe water. as sodium ions are heavier than calciumor magnesium the tDS will increase slightly, whilstpH and alkalinity will effectively remain constant.

advantages to the barista are that their equipmentwill no longer be at risk of scaling. thedisadvantages are increased sodium and tDSlevels which may impact coffee quality.

these softening systems can often be regeneratedat end of life either manually or automatically.

urBan MytH: the use of Sodium softening isillegal for drinking water. not technically truealthough in most countries it is recommended thatSodium softening is not used for drinking water.the elevated Sodium levels may mean that thewater is no longer “potable” according to localwater regulations.

WEAK ACIdIC CATION RESINSde Carbonisationthe vessels of these water treatment units containsmall plastic beads (resin) charged with hydrogenions. the resin will exchange their hydrogen ionsfor calcium and magnesium ions associated withthe carbonates. calcium levels are now reduced sothe water hardness and tDS will also reduce. Withthe carbonates effectively removed and the waternow laden with hydrogen the pH will dropdramatically, typically as low as pH 4.5.

to help counteract this low pH most systems ofthis kind incorporate a blending bypass to limit thesoftening effect of the resin. When properly set thepH on a new system is likely to be in the region ofpH 5.5 - 6.0.

Bypasses can be either fixed or operator adjustable. they can be a simple hole allowing thewater to pass through and can be sensitive to

variations in water pressure or flow rates.alternatively they can be highly engineered designswhich provide a consistent performance for allwater conditions.

nOtE: Where a filter incorporates a bypass, checkthe level of filtration offered to the bypassed water.

SCALE CONTROL

SCALE INhIBITORSPhosphatesScale inhibitors are often phosphate salts dosedinto the water. there are many forms of phosphateeach having their own particular characteristics.

urBan MytH: there is speculation regarding thesafety of consuming phosphates.

phosphate in black coffee: 50 mg/litrephosphate in a cappuccino: 250 mg/litrephosphate in a typical cola beverage: 700 mg/litre

When phosphates are used in water treatment,they interfere with the formation of some chemicalcompounds such as calcium carbonate that areinsoluble in water. they do not soften the water,merely inhibit or slow down the formation of thesescale forming compounds. phosphates can also beutilized in helping to prevent equipment corrosion.

5. EVERPURE • WATER FOR COFFEE LOVERS

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MINERAL REdUCTION

Reverse Osmosisa reverse osmosis system is based around asemi permeable membrane which only allows thesmallest molecules (Hydrogen and Oxygen ions) topass through. the remaining ions are washed awayto drain.

When specifying a reverse Osmosis system anumber of factors should be considered.

Some rO systems have a relatively low waterproduction rate. to ensure sufficient water isavailable for peak demands an external storagetank is often recommended. If the water pressuresupplying the membrane is low, the system mayneed a water boost pump.

traditional rO systems can waste a lot of water,increasing utility costs. High Efficiency systems arenow available offering high water recovery rates.

rEvErSE OSMOSIS SyStEM arE typIcallyavaIlaBlE In tHrEE DIFFErEnt StylES

• rEvErSE OSMOSIS: WatEr Onlythese systems often produce a water that isdevoid of the minerals you require to make agood coffee. the water is also likely to beaggressive to coffee equipment.

• rEvErSE OSMOSIS: WItH BlEnDIngthese systems allow blending of a proportionof filtered tap water to achieve the desired tDSlevels. the complexity of the blending systemused will dictate the stability of the treated water.

• rEvErSE OSMOSIS: WItH calcIuM DOSIngthe treated rO water is passed through a bedof calcium which then dissolves back into thewater to achieve a balanced, re mineralizedwater quality. a number of coffee equipmentmanufacturers are starting to show apreference for this type of system for use inareas of high chlorides, to prevent any bypassblending of the chlorides back into the water.

SUMMARY

Now you know what’sin water and how itcan impact coffee tasteand coffee brewingequipment. You alsohave an insight into thecommon treatmentmethods currentlyavailable and how they willaffect your water. So whatshould you do next…

• Obtain an analysis of what’s in your localwater. this can be obtained freely from yourmunicipalities water supplier, and will probablybe an average of their readings for your watersource over the last 12 months. If the supplysource changes so can the water quality.

Self-test the main contaminants with easy to useand relatively cheap test equipment. this will alsoallow you to keep an eye on your water quality andallow for seasonal fluctuations.

Invest in a full water analysis from your tap.this will highlight any issues for your individualpremises.

• Decide on what you want your brew water to looklike. tDS levels ? Hardness ?

• Select your preferred Filtration and watertreatment partner. your supplier should offer thefull spectrum of technologies.

• Work with you Filtration supplier to specify asystem that meets the needs of your businessand falls within your budget for capitalexpenditure and operational costs. Ensure youchoose a system that doesn’t just meet yourneeds now, but has the capacity or can be easilyexpanded to meet increased demand as yourbusiness grows.

© MAY 2018 pentair / Everpure. DISclaIMEr: While every reasonable effort is made to ensure that the information provided in this booklet is accurate,pentair, its employees and agents will not be held responsible for any damage to equipment, however arising, from the use of, or reliance upon this information.

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