Beer consists of more than 90% water. Brewing water quality is many times higher than ordinary drinking water. In Denmark, well water and surface water are used for brewing. To produce one litre of beer you need about 3½ litre of water.
Water for brewing should be: potable, clear, tasteless and odourless
Some undesirable parameters are:
Water chemistry in connection with brewing is very complex; anion (negative ions) and cations (positive ions) are mixed and some are soluble others are insoluble when mixed with cereals, hops and other brewing ingredients. Beer types originating from renowned part of the world, is normally today, produced with water close to the chemical composition of this area; these beer types could be:
In connection with brewing the content of cations and anions is important to know as these ions will influence the perceived taste of beer.
Important ions to take into consideration
Calcium (Ca2+) are an important cation to regulate the pH of the beer, involved in the precipitation of oxalate ions with could cause gushing in beer and do affect the taste of the beer in connection with anions.
Magnesium (Mg2+) is an important cation to regulate the pH of the beer
Sodium (Na+) – biggest pH increase with HCO3- and cause a salty taste when connected with Chloride in large amounts.
Bicarbonate (HCO3-) increases the pH when connected with all cations and please take care of the scaling effect causes by bicarbonate.
Chloride (Cl-) is giving a sweet taste in low concentration and a salty taste to beer in higher concentration. This anion is also corrosive in connection with stainless-steel!
Sulphate (SO42-) is in higher concentration influencing the taste and giving a beer with a more dry aftertaste.
Jens Eiken, Master Brewer