I guess the subject says it all…
I have seen it written many times that you should always use cold (as opposed to warm or hot) water to brew good tasting coffee in almost any kind of machine, but I can’t figure out why the temperature of the water would make that much of a difference.
Does anyone know the truth of the matter or are we just perpetuating an old wife’s tale?
Hot water tends to have more dissolved minerals than cold water. Not only can this affect the taste of the coffee, but scale and lime deposits inside the coffeemaker are a bitch to remove.
According to the Quetzal Coffee Company (www.zuetzal-coffee.com), the ideal temp using a hot water method is 190-200 degrees F. “This permits ideal extraction of essential flavor and oils from the grounds. Water that is too hot will over-extract, yielding a less than desirable cup of cofffee. Likewise, water that is too cold will under-extract, yielding a thin lifeless cup.”
I remember hearing somewhere that hot water has more minerals and particles than the cold, because they dissolve better in the hot or something. I have also heard to always start with cold tap water when boiling water or anything in water for the same reason.
www.cctm.com/tr.htm says hot water has been sitting around in your water heater and may have a reduced oxygen content, which is important for flavor and aroma. It also says don’t over-boil or it will de-oxygenate; bring to just boiling and use.
In the US at least, a large proportion of homes have a water softener hooked up to the hot water supply. The water that a softener puts out is slightly salty, so coffee brewed with that hot water is also slightly salty.
Because, simply put and ignoring the science of it all, hot water makes the coffee sour.
Fair enough… thanks all!
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Huh? I’ve always associated with well water; never with city water or hot water supplies. Regional thing? Here in Michigan I don’t know anyone with city water that has a water softener, but we have good, non-hard water supplies – I know that it’s not necessarily true in the entire country. Are water softeners really that common?
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I think there is another reason besides water quality: coffee makers are designed to work with cold water! Coffee makers work by heating small amounts of water at a time, and using the steam to push the drops of hot water up a pipe. If you use hot water, I think the water will boil faster and the hot water will flow into the filter faster.