Striving to Balance Quality Water with Minimal Environmental Impact
Quality water is essential to achieve the perfect cup of coffee and tea. However, the methods to accomplish this and the environmental impact must be taken into consideration, and creating this balance is not easy.
By Anne-Marie Hardie
Life wouldn’t exist without water. It is an essential part of every living organism. The developed world is under an illusion that water, as we know it, will continually flow. This is simply not the case, water is a finite resource. The water that we have here today is the same liquid that existed millions of years ago. Although 70 percent of the earth’s surface consists of water, only one percent of this water is consumable. We add chlorine to our pipes to disinfect, fluoride for health, and salt to remove the hardness – each of these minerals compromise the environment and the overall quality of our cup of water.
Water’s footprint is vital to the long-term sustainability of this essential resource. Thus, scrutinizing the environmental impact of the methods used to modify the water to reach the desired standard is critical.
“Every water has a different taste profile,” said Cindi Bigelow, president and CEO, Bigelow Tea, Fairfield, Connecticut. “You want the one that tastes the most neutral, with a lower mineral content.” This is particularly true for herbals and milder tea flavours. “When drinking chamomile, you want the subtlety of the taste, that sweet honey- like flavour to come through.”
The Gold Standard
On the quest for a perfect cup, we must pay close attention to its core ingredient – water. “Coffee is up to 98 percent water, if you miss with the water you will have difficulty crafting a consistently good coffee or tea that is appealing, aromatic, and tastes good,” said Keith Black, managing partner, Waterwise, Alcoa, Tennessee. The industry standard for water is to strive for a neutral flavour so that the taste and aroma of the beverage will come forward.
“It’s a conversation that has been going on for hundreds of years,” said Daniela Cubelic, tea master, Silk Road Teas, Victoria, British Columbia. “There were essays written centuries ago about tea and water quality.” She shared that one of the ancient ideas recommended using water from the region where the particular tea was grown. This would be a naturally harmonious relationship as the leaves would be unfurled by the same water that grew them. This method is both economically and environmentally unsustainable.
Naturally occurring, alkaline water is challenging to find. This leaves the industry with two choices: bringing in bottled water from external resources or modifying their own tap water. Bottled water, which from a quality control standpoint makes logical sense, has an extensive carbon footprint. “We arrived at a moment, we need to confront what is going on with all the bottled water,” said Cubelic. “It’s time to move the discussion in a different direction. I don’t think it’s a good practice to recommend bottled water anymore.”
This leaves companies looking at the water in their own backyard and the method needed to achieve the desired standard of water quality. “Stronger tasting teas can handle a higher mineral content in the water, however, delicate flavours such as green or white require a very mild water,” said Cubelic. The aim is to use a water that is as close to flavourless as possible so that it brings forth the flavour of what you’re brewing.
“Before we get into the scientific measures, run the water and taste it,” recommended Paul Stack, Marco Beverage Systems, Dublin, Ireland. “Does it smell good, taste bad? Trust your palate.”
Bigelow recommends using fresh, cold water when brewing a cup. “It is the bubbles and the aeration in the cold water that will help unfurl the leaves.”
When using tap water, we are at the mercy of the environment and how it alters the flavour of the water. Seasonal factors, such as salt on the road in the winter, can impact the amount of minerals in the water. “From a taste view point, you want to be looking for a neutral pH 7,” said Stack. “As the hardness increases, there will be a more pronounced effect on the nuanced flavour. Softer water allows for the flavours to be highlighted not battled.”
What is in the Water
To truly understand what is in the water, Black recommends that at minimum investing in a quality TDS (total dissolved solvents) meter. This meter will gauge the overall solvent levels in the water and help to determine the best solution for filtration. However, this is only part of the picture. An extremely low TDS level could impact both the flavour and the extraction process, potentially resulting in an over extracted brew. The target TDS from the Specialty Coffee Association (SCA) is 150 ppm, with an acceptable range of 75-250 mg/l. Tea is not far off, with the recommended range of 50-150 ppm, with the ideal amount remaining at 150ppm.
Tap water is often within this range. However, there are other undesirable attributes that will have a negative impact on the flavour. This includes chlorine, ammonia and iron, all which will negatively affect the taste of the brew. “At bare minimum you want a carbon blocker to remove the taste and odours, and a proportion of the particle matter,” said Stack
Hard water can be particularly devastating on both the beverage and the machinery, as it causes limescale deposits and other residues that can cause failure of the element or boiler. “Acidic water is an enemy of machinery,” said Stack. “Anything below a pH of 7 can be extremely aggressive to stainless steel boilers and equipment, potentially resulting in corrosions on the tank, leaks and overall equipment failures.” Hardness may also have a pronounced effect on the nuanced flavour of the beverages. “Our conversation is always twofold. We talk to people about the machine and the effect that water has on the beverage, and the beverage and the effect of water on the machine,” said Stack.
As far as taste goes, chemist Christopher Hendon, University of Bath, cautioned that not all hard water is necessarily bad. According to his study, “The Role of Dissolved Cations in Coffee Extraction,” published in the Journal of Agricultural and Food Chemistry, magnesium in water sticks to eugenol providing the brew with a woodsier taste. These higher magnesium ion levels also aid with the extraction of the coffee. Water that is too soft will decrease the overall flavour extraction. “A certain level of hardness in water is desired so that it can act as a catalyst for coffee extraction,” said Stack.
Filtration systems can help alleviate these concerns by removing the elements that compromise the beverage. However, Black advised that determining the water level should not be based on a strict formula. “The idea of the right level of mineral content will vary according to what you are brewing,” said Black. “This includes the type of beans, size of the ground, and the temperature that you are brewing.”
Integrating a filtration solution aids with quality control and consistency. It is important to review these solutions through a sustainability lens prior to implementing. This includes looking at how the waste water is disposed and what elements this water is adding back into the environment. California, for example, has halted the installation of salt-based softeners in all new construction, to limit the negative impact of the salt water brine.
Reverse osmosis has been the gold standard for filtration methods. Black cautioned that this method, if not optimized, can be both wasteful and detrimental to the environment as the heavily mineralized waste water enters the sewage system. Ideally, the water should be measured and manually adjusted to meet the specific brewing needs of the beverage. This will help minimize the negative impact, while also ensuring that the adjustments are made in response to the specific needs of the water.
An emerging form of filtration technology is Membrane Capacitive Deionization. This process uses electrical currents to remove the impurities in the water. With this technology, an operator can dial in the amount of TDS or mineral content that remains in the water. “It’s interruptive technology which is going to change the way that water is processed in North America,” said Black.
Quality water is essential to achieve the perfect cup but the methods to get to this water needs to be heavily considered. “It’s a fine balance,” shared Cubelic. “The industry wants quality water to bring out the flavour, but we also need to look at the environmental impact of the filtration methods chosen.” She noted that over the last six to eight years, the overall awareness on the impact of water for beverages has dramatically increased. “However, we need to continue to propel the industry further to not only look at the desired water but the most sustainable method to achieve this goal.”
Anne-Marie Hardie is a freelance writer, professor and speaker based in Barrie, Ontario. She may be reached at: [email protected]