Free BJCP Prep Course: Class 5 -Water

Your water source is drinkable?

• remove chlorine: boiling of off-gassing(sit overnight)
• remove chloramine: charcoal filteration or campden tablet(1 tablet/20gal)
• reverse osmosis(RO)=all minerals stripped out
• BJCP states RO or deionized water<mineral or spring water

Alkalinity, pH, hardness?

• water=negative anion(hydroxide OH-)+positive cation(hydrogen H+)
• pH=the concentration of hydrogen ions(H+)
• eg. pH 7 means: same amount of H+ and OH-
• higher concentration of hydrogen(H+) ions=lower pH(acidic)
• higher concentration of hydroxide(OH-) ions=higher pH(alkaline/basic)
• alkalinity is a measure of the capacity of the dissolved anion(eg. HCO3-, bicarbonate)
• bicarbonate(HCO3^-)+calcium(Ca²⁺)=calcium carbonate precipitate+water+carbon dioxide
• means reducing amount of bicarbonate=reducing alkalinity
• permanent hardness: remaining cations after precipitate(eg. Ca²⁺, Mg²⁺)
• these are permanent: from sulfate or chloride salts
• these are temporal: from carbonate or bicarbonate salts <- after boiling, it remove 

Why pH and minerals so important?

• an enzymatic degradation of phytin->form of phytic acid(storage of phosphates)->release phosphates->combine w/ calcium or magnesium->calcium(magnesium) phosphate+hydrogen(H+) ion->optimal pH!(5.2~5.7)=mash with excellent efficiency
• if your water have too much alkalinity: 
• add gypsum salt or epsom salt
• add phosphoric acid or lactic acid(short cut)

Important ions in brewing water

• cations
• calcium 
• essential for reducing pH
• keep oxalate salt(clarity)
• reduce tannin
• aids protein coagulation(precipitation)
• magnesium
• less effective than calcium
• put too much, harsh mineral taste
• sodium: sweet. put too much, salty
• anions
• bicarbonate(HCO3^-)
• determine alkalinity
• neutralize acid from dark/roasted malt
• increase tannin and color(darker) <- brighter beer=acidic water
• sulfate(SO4^-2): bitterness and dryness
• chloride(Cl^-): sweetness(at lower level). put too much, hamper flocculation

Related fault

• sulfur like: check ion content if not a lager
• metallic: check high ion content
• harshly bitter: check sulfate level
• overly malty: check chloride level
• salty: check sodium content or add too much salt?