1 . Odor
One of coffee’s most distinctive and inviting characteristics is its aroma. Studies have indicated the smell of freshly brewed coffee alone is enough to improve mood and performance in test subjects.
To preserve that tantalizing coffee smell, all water used to brew coffee should be completely odorless. Chlorine, widely used to disinfect city water supplies, is notorious for imparting a stinging, pool water-smell on water.
Hydrogen sulfide leaves water with a pungent, rotten egg odor. Phenol compounds in water can leave a medicinal, sickly sweet odor whereas bacterial presence can leave water smelling like decay.
Obviously, any of these scents are enough to interfere with the fresh smell of coffee, not to mention repulse the coffee drinker. Any odor-causing contaminant should be completely removed from the water before brewing.
The pre-treatment of your water will depend heavily on the composition of your water, as different contaminants require different filtration approaches.
If you’ve identified an off-putting smell to your water, start by conducting a water test. This detailed report will illuminate the source of the foul smell in your water.
2. Color
Coffee should be brewed with water that is completely clear in color. Any cloudiness, discoloration, or tint should be eliminated from the water prior to brewing.
This is both an aesthetic and a taste concern. Red or orange coloration is often indicative of the presence of heavy metals like iron, copper, or rust particles.
This can manifest in your water from aging, corroded pipes and is prevalent in groundwater supplies. While these don’t necessarily pose health concerns, they can leave a metallic taste in the water as well as ruin the color of the brew.
Sediment is extremely undesirable in the water, as it not only mars the color, it very likely could lead to a dirty or gritty taste.
To ensure you provide your customers with the mahogany-colored cup of coffee they expect, all water used to brew coffee should be totally clear. The most effective means of removing floating debris and particulate matter is through mechanical filtration.
Sediment filters will sieve out any sand, silt, or dirt particles making their way into your water. Sediment filters are micron-rated to remove particles even past the limit of human visibility.
Turbidity (the measurement of the loss of water’s transparency due to suspended particles) is easily solved by installing an inline sediment filter with a fine micron rating.
3. Chlorine
The contaminant that poses the biggest threat to your perfect cup of coffee is chlorine. Chlorine is a disinfectant commonly used by municipalities to eliminate bacteria and waterborne pathogens from drinking water. While it’s entirely safe to consume, chlorine is characterized by its sharp, unpleasant odor and its bitter chemical aftertaste.
Any detectable level of chlorine will tarnish the coffee’s flavor profile with a harsh aftertaste and prevent the coffee bean’s unique flavor notes from translating onto the palette.
To meet the SCA’s standards for brewing, the water cannot contain any traces of chlorine (0 mg/L) because of the overpowering negative consequences. If your coffee shop is on the city water supply, you will need to take steps to reduce the chlorine in your water.
Carbon filters are the water industry standard for eliminating chlorine from water. Through adsorption, the chlorine attaches itself to the expansive, porous surface area of the activated carbon.
A carbon filtration system is a necessary component of any coffee house filtration system. The reduction of chlorine will ensure your roast’s character isn’t compromised by any chemical taste or smell.
Chloramines are an increasingly popular water disinfectant utilized by water treatment facilities. Chloramines are a more cost-efficient and longer-lasting alternative to chlorine and are created by the addition of both chlorine and ammonia to the water supply.
However, chloramines are more difficult to remove and require extensive contact time with activated carbon for any significant reduction to transpire. Because of this, catalytic carbon is preferred for chloramine reduction.
Catalytic carbon transforms the chlorine and ammonia into chloride, ammonia gas, and nitrogen gas. When sized properly, commercial catalytic carbon filters can eliminate chloramines from your water without compromising flow rates. Obtain a copy of your water distributor’s consumer confidence report to determine if your water treatment plant is using chloramines as a disinfectant.