# Water hardness - can you taste it?



## seeq (Jul 9, 2011)

I live in a hard water area (282mg/l calcium carbonate) I filter my water, but at the moment don't soften it. We all know the obvious effects re limescale. But does it have an effect on the flavour of the coffee we produce? is it noticeable? and has anyone really experimented with it?

If I was going commercial I would probably install a water softener, alone I'm sure it would be worth it to prolong the life of the hardware, but would it improve my coffee?


----------



## MikeHag (Mar 13, 2011)

Im interested in this. Will do some reading.


----------



## seeq (Jul 9, 2011)

I have done some research and dug myself into a scientific hole again! I'm in a bit over my head here, but this is what i understand so far:

Water is a bit of a nightmare, it is unique in the fact it is a solvent and has an effect on pretty much everything (hence the reason it causes rust, wears down rocks, etc) it picks up pretty much everything and dumps it in our pipes so to speak. Calcium carbonate's solubility in water is dependent on the amount of CO2. This is reduced when water is heated, hence the reason calcium carbonate is less soluble in heated water (thus leaving a nice scaley deposit in your beautiful boiler). This aside, harder water still will let enough calcium carbonate through the heating and extraction process to still be present in an increased amount over soft water. So as a result calcium carbonate is reduced when the water is heated (pressure has an effect on it too, i havent yet worked out exactly what!).

Calcium carbonate in water actually reduces the solubility of water. So in effect 'hard water' takes less of the flavours and oils from the coffee grounds as it passes through. To what extent I have no idea.

This leads me to another question (having not really answered my first!). If water pulls less of the oils and flavours from the coffee proportionate to it's hardness, do we need to consider how to counteract this. A longer extraction time is going to take more of the oils, but obviously more water, however maybe a higher dose would counteract the lack of solubility of hard water.

Conclusion: If a difference of soft and hard water does noticebly effect the flavour, it's likely to be due to the lower solubility of hard water and it's ability to extract flavour. Hard water = increase dose?

Discuss!


----------



## MikeHag (Mar 13, 2011)

Will come back with a more considered reply but for now it's good that you've pinned hardness/softness to solubility. I've read that overly soft water is too acidic for coffee (words to that effect). In my area the water is very soft and very pure. TDS is 37 ppm. (don't know enough about softness unit of measure). Anyway, Point is, back when I lived in London water was hard and tasted crap. Here it tasted good. Maybe that means soft water makes better coffee, maybe not. 'too pure' is my fear. Oversolubitily. Discussion and research continues...


----------



## seeq (Jul 9, 2011)

Quoting the bible (on Food and cooking - Harold McGee):

Brewed tea and coffee are 95-98% water, so their quality is strongly influence by the quality of the water used to make them. The off-flavours and disinfectant chlorine compounds of most tap waters are largely driven off by boiling. Very hard water, high in calcium and magnesium carbonates, has several undesirable effects: in coffee, these minerals slow flavour extraction, cloud the brew, clog the pipes in espresso machines and reduce fine espresso foam [crema].... Softened water over extracts both coffee and tea and gives a salty flavour. And very pure distiller water gives a brew best described as flat, with a missing dimension of flavour. The idea water has a moderate mineral content, and a pH that us close to neutral, so that the final brew will have a moderately

acid pH of around 5, just right to support and balance the other flavours.

I'm beginning to think that water quality has a bigger impact on espresso than I first realised. So far I have come to the conclusion that soft water would be best balanced with a gram or two smaller dose and a darker roast. Very hard water would be best to counteract with a slightly higher dose and a lighter roast which will bring it's own acid flavours to neutralise the alkaline of the calcium and magnesium.

Mike, I think you are right from what I have read that soft water does give coffee a more acidic taste (more accurately a less alkaline taste). Harder water gives a more alkaline taste and less flavour extraction.


----------



## 20Eyes (Mar 16, 2011)

Always use room temperature Evian bottled water for all my brewing methods. It's one of the few bottled waters to have a Calcium content towards the middle range of moderately hard, ie, it's not too soft. Not only does it mean consistency and a purer flavour, it's also better for the internals of the machines (the area I live in is notorious for hard water).

The difference in taste between that and tap water is quite noticeable.


----------



## Coffeelogicuk (Apr 30, 2011)

I use tesco value filtered water and it works nicely, no problems at all with scale and coffee tastes great. Nice choice of topic btw!


----------



## altyris (Aug 27, 2011)

I have to admit I'd never really given this much thought (too preoccupied with aspects of technique at present as I am). I will definitely start looking out for this now though - interesting topic!


----------



## RolandG (Jul 25, 2010)

Definitely an interesting area - I'm lucky to quite like the water in my area for hardness!

Colin Harmon covered some of this in his Signature Drink for WBC 2010 - you can see the LiveStream, worth a look







- http://www.livestream.com/worldbaristachampionship2010/video?clipId=pla_cbf65ce8-1f51-4915-b8e0-ce03fdc8c097&utm_source=lslibrary&utm_medium=ui-thumb


----------



## RolandG (Jul 25, 2010)

Definitely an interesting area - I'm lucky to quite like the water in my area for hardness!

Colin Harmon covered some of this in his Signature Drink for WBC 2010 - you can see the LiveStream, worth a look







- http://www.livestream.com/worldbaristachampionship2010/video?clipId=pla_cbf65ce8-1f51-4915-b8e0-ce03fdc8c097&utm_source=lslibrary&utm_medium=ui-thumb


----------



## Stevenp6 (May 17, 2011)

Coffee is 98% water, so it is the most important ingredient of them all. Don't think softened water is necessarily the answer, just use a good quality water filter to take out any impurities from your current supply. It is the heavy metal ions and chemicals such as chlorine that effect the taste and aroma of the final beverage. Softened water will protect equipment from scaling up however which can save a lot in repair bills. Water softener companies advise you not to drink the water that has passed through salt based softeners as it contains too much sodium content. Water filters are the answer.


----------

