When it comes to making a great cup of coffee, many people focus on the beans, grind size, and brewing. However, one crucial element that often gets overlooked is water. Since coffee is more than 90% water, its quality can make or break your coffee. To dive deep into this topic, we sat down with Willow, one of Padre Coffee’s expert baristas at our Brunswick East location. With extensive experience in coffee and a keen interest in understanding how water affects brewing, Willow gives us her insights to help level up your coffee game.
Watch our interview with Willow below to hear her thoughts on water quality, temperature, and more:
In this blog, we’ll explore water quality, temperature, and mineral content.
Water quality is crucial because coffee is primarily water. As Willow highlights, “If the water doesn’t taste good and it doesn’t work with the coffee you’re brewing, you’re going to have 90% of your drink tasting really bad”. Even the best coffee beans can result in a disappointing coffee if the water quality is subpar.
Minerals in water directly influence extraction. Too few minerals can result in under-extraction, where the coffee is weak, while water with too many minerals, like calcium, can lead to over-extraction, producing harsh, bitter flavours. The right balance ensures the best possible extraction and brings out the coffee’s unique flavours.
Willow suggests using water that is “clean tasting and leans on the softer side”, meaning low to moderate mineral content for a balanced extraction. This allows the coffee’s natural flavours to shine without overpowering the brew.
Yes, depending on your location. Tap water varies in mineral content and purity. “In Melbourne, we have very soft water that really suits brewing coffee,” Willow explains, while harder tap water, like in Adelaide, can lead to bitterness and metallic notes. Filtering tap water is key in hard water areas to avoid negatively affecting the coffee’s taste. But we recommend using filtered water where you can.
Bottled water might improve your coffee, but it depends on the brand. Some bottled waters contain too many minerals, which can lead to over-extraction. Check the water’s mineral content before use.
Spring water works well if it’s not too high in minerals. “A spring water that’s relatively low in mineral content is going to be really good for brewing coffee”, Willow suggests. However, high mineral content spring water can lead to over-extraction and a bitter brew, so filtering it or choosing balanced spring water is the safest bet.
Distilled water isn’t ideal for coffee because it lacks the minerals necessary for proper extraction. “Minerals are part of the chemical reactions that occur to extract flavour from the coffee,” Willow explains. Distilled water can lead to flat or sour coffee, while water with too many minerals causes over-extraction. The goal is to find a balanced water source.
Magnesium, calcium, and sodium are the key minerals in water that affect coffee extraction. Higher calcium enhances sweetness, while magnesium boosts complexity. Sodium bicarbonate neutralises acidity, balancing the overall flavour. Willow suggests using a magnesium-rich water source, such as aBWT filtration system, as the optimal choice for brewing coffee.
Water temperature directly affects the extraction process by controlling the speed at which flavours are drawn out from the coffee grounds. Hotter water extracts flavour faster, Willow explains, “If you have your water up at 100 degrees, the chemical reactions that occur when coffee brews are going to happen a lot faster”. On the other hand, cooler water slows extraction, which can result in weak or sour coffee.
For best results, brew filter coffee between 88°C and 98°C, and espresso between 89°C and 94°C. Adjusting water temperature allows you to fine-tune your brew to either balance out acidity or smooth out bitterness.
Using atemperature-controlled kettle, like the Fellow Stagg EKG Kettle, gives you precise control over your brew. “We’re looking anywhere from 88 to 98 degrees” for filter coffee at home, according to Willow, which allows you to tailor your brew to the beans you’re using and your taste preferences.
Following manufacturer guidelines is important, but Willow suggests keeping an eye on water quality and changing filters every one to three months, depending on usage. She also notes, “If the water from your coffee machine tastes bad before you even brew the coffee, the coffee’s probably going to taste bad as well”.
The simplest way to test water quality is to taste it. Willow recommends tasting hot water straight from your espresso machine. If it’s minerally or harsh, your coffee will likely taste the same.
Water is often overlooked in the coffee-making process, but its quality can significantly impact the taste of your brew. By using clean, filtered water with the right mineral balance, you can unlock flavours in your coffee that elevate your game. Adjusting water temperature and switching to filtered or softer water are simple tweaks that make a world of difference.
Remember, your coffee is 90% water – make sure it’s the best it can be!
Padre Coffee acknowledges the Traditional Custodians of Country throughout Australia and their continued connections to land, sea and community.
We pay our respect to Elders past, present and future, and extend that respect to all Aboriginal and Torres Strait Islander Peoples.
