In preparation for UK Coffee Week HER was invited to an event focusing on the importance of water to coffee. Gary Norwood from Brita Professional, gave us all a chemistry lesson and showed how it is very important to know what is in the water you are adding to your coffee and how to go about filtering out what you don’t want. As one of only two ingredients in HER Cold Brew Coffee Concentrate it is something we take very seriously.
London water is notoriously hard with a typically high TDS or total dissolved solids reading. As a result untreated water from London taps has a different taste to water elsewhere in the UK. Whilst TDS is a good measure of the quantity of dissolved solids in water it does not help identify the specific ions in the water. The effect of the composition of these dissolved solids is of huge importance when this water is used to brew coffee. When Magnesium is dissolved in water the resulting ion binds to citric and malic acids drawing out brighter more acidic flavours while Calcium ions draw creamier flavours from the grounds. Filtering water so that it falls in the sweet spot flavour wise for our coffee is not a simple process and involves a lengthy testing process but we think it is worth it. That is why the taps at HER are fitted with a well adjusted filter so that every coffee brewed on site at HER, includng HER Cold Brew Coffee Concentrate, will have taste the best it can.