The word “sustainability” is commonly used in specialty coffee. Consumers are more aware than ever of the impact of their food and beverage habits, and rightly want to drink “sustainable” coffee.

But as much as sustainability means buying good, ethically-sourced coffee, it also means being mindful of your waste and your environmental impact. 

As a result, some consumers are moving back to traditional, reusable methods of coffee brewing, or looking for eco-friendly alternatives to paper filters. To learn more about a few different “green” home brewing methods, I spoke to a few baristas.

Lee este artículo en español Preparación Ecológica de Café: 4 Alternativas al Uso de Papel

What Does A Paperless Cup Taste Like?

Before we look at different ways to make coffee at home without using paper filters, let’s consider how this affects the flavour of your cup.

While primarily we use paper filters to stop coffee particles from ending up in our cup, paper also affects the flavour of coffee in a variety of different ways. Coffee contains a huge variety of different compounds, including carbohydrates, lipids, acids, proteins, and more. 

Paper filters retain some of these substances – namely lipids, some acids and astringent polyphenols (such as tannins). As a result, paper-filtered coffee generally has a cleaner and lighter profile, as these compounds are removed.

When they aren’t filtered out by the paper, however, these compounds provide greater density in the cup, leading to a “thicker” beverage with a heavier mouthfeel. 

Reusable methods for filtering coffee (like metal or cloth) will allow more of these compounds to pass through. This results in a flavour profile that is generally heavier and more intense. However, it also means there is more likely to be sediment in the cup. 

Lucci Salomão is a Brazilian barista and a Q grader. He tells me that there is no “right or wrong” brewing method or filter material. “There is no ‘bad’ method,” he says. “Just those that are inappropriate for a certain moment or for your taste.”

Cinthia Bracco is a barista and the owner of Astronauta Café, in São Paulo, Brazil. She tells me that Astronauta has a 100% vegan menu and is focused on sustainability. As such, Cinthia and her team often brew with reusable methods like the French press, stainless steel mesh filters, and metal AeroPress filters. 

Cinthia explains that in Brazil, pour over with a paper filter is the most popular way of brewing filter coffee. She says that even though many of her customers were initially apprehensive about metal filters, demand has increased. 

However, with any reusable brewing method, cleaning is of paramount importance. If compounds and oils accumulate over time in a reusable filter, they can have a lingering taste that will affect the flavour of future brews.

You may also like Making Coffee At Home: What’s The Best Beginner Coffee Brewing Method?

Green Home Brewing Guides: Reusable Methods

So, we know what to expect from coffee made with a reusable filter. Now let’s look at some specific brewing methods in more detail.

The French Press

The French press is an paperless alternative to brewing pour over filter coffee. Most French presses come equipped with a fine metal mesh filter, but the quality of the filter will vary. As more oils are able to pass through the mesh filter than they are with a paper filter, coffee brewed with a French press often has a thicker, heavier mouthfeel.

As the French press is an immersion brewing method, the coffee is exposed to water for a longer time than it would be in a pour over dripper. Because of this, your grind should be coarser than it would be for filter coffee. 

Lucci says: “When brewing with a French press, you can play more with your grind and ratio… if it’s a darker roast, you might grind coarser; for lighter roasts, maybe finer – but all within the range of what we could normally call ‘coarse’.”

To experiment with the French press, you can also tweak your water-coffee ratio and the brew time. Lucci says that he specifically likes to play around with brew time, saying that “between two and six minutes [brew time]… you can test a lot”.

Lucci’s recipe allows for a lot of experimentation with ratios and timings, but is fairly simple:

• Coarsely grind 70g to 85g of coffee per litre of water
• Add it to your French press
• Soak the grounds with just enough water to completely immerse them, allowing for preinfusion (similar to blooming with pour over methods)
• Add the rest of your water in a continuous, centred flow
• Brew for four minutes, then plunge

Cinthia recommends that brewers check their French press before they buy. “You have to see if it can be completely dismantled for washing. Also, make sure the glass or plastic used can handle high temperatures.”

Moka Pot

Since the moka pot’s invention in the 1930s, it has become an established way to brew a heavy, intense coffee.

Lucci says that despite the moka pot’s relative familiarity, he thinks it is often overlooked. “There are people who don’t the moka pot because it gives you a stronger coffee. But if you don’t like it, it’s not because it’s a bad coffee, it’s just because this kind of coffee doesn’t suit your taste.”

The most important thing with the moka pot is using the right ratio. However, the moka pot is made with indications on the equipment itself for the water and coffee levels. This makes it much easier to get it right.

It also means that it’s easier to replicate the same beverage when brewing over and over again. Lucci says: ”The moka pot and French press both have repeatability, which is a great advantage.”

Your coffee-water ratio will be low – around 1:8 – which creates a drink that is heavy and intense. As the moka pot is a stovetop coffee brewer, the coffee is extracted at a high temperature. This, along with the comparatively low brew ratio, can affect some of the more delicate flavour notes in a coffee.

As a result, Lucci recommends using coffees that have tasting notes of chocolate or caramel. He says: “Consider using medium-dark roasts, or other more structured coffees with sugars and oils that develop well during roasting.” 

Some tips for brewing with the moka pot:

• Use a low flame, preferably on a gas stove
• Adhere strictly to the marks on the equipment (your water should come up to right below the safety valve, and your coffee should fill the filter tunnel without tamping)
• Leave the lid open during brewing. When your chamber is full about halfway with coffee, turn off the heat, close the lid, and let it finish on its own 

Cloth Filters

Brewing coffee with a cloth filter – also known as a “sock” – is a very old tradition. It is believed that the first coffee filter in history was made from cloth, supposedly dating back to 19th century Japan. It is still popular in coffee-producing regions today.

Cloth filters offer an in-between option when it comes to mouthfeel and intensity. The fabric offers less resistance than paper, but it still absorbs some of the oils, leading to a balanced final cup.

Giovanna Serrano is a Venezuelan barista based in Brazil. She recently launched Fabrikafé, a brand that sells cloth filters in different formats – not only the usual “socks”, but also fabric filters for cone and flat bottom drippers. 

She believes that cloth filters work for pretty much any coffee. “I think any coffee can work well for cloth. It depends on the experience you want… the important thing is to know what kind of extraction the dripper will offer you.”

She adds: “I have to think about my extraction, to make sure that it doesn’t [extract] too fast when using the cloth. I grind the coffee a little finer, or stir the coffee bed a little more.”

Giovanna has a few tips for brewing with and taking care of a cloth filter:

• Boil it for at least one minute before use
• Rinse the filter and the support (if using one) with hot water
• Use 12.5g of medium-ground coffee to 200ml water
• Pour your 200ml water in four parts (not necessarily even). Make sure the first pour wets the entire coffee bed
• Stir or swirl the filter after each pour

As the fabric absorbs some of the oils and compounds in coffee, you should make sure you clean your cloth filter properly. As well as boiling it before you brew, you should clean the filter as soon as you finish brewing, by rubbing it clean under running hot water.

If you intend to use the filter twice in a 24-hour period, you can immerse it in a pot of water and place the pot in the fridge. If it’ll be longer than 24 hours before you use it again, you can also place the wet, cleaned filter into a plastic bag, and place the bag in the freezer. Storing the filter at low or freezing temperatures will kill any microorganisms present in the cloth. 

Change the filter once every three months, or more frequently if you use it often. “A good indication that it is time to buy a new cloth filter is when it feels choked even after pre-heating and boiling, and if it retains a lot of the wet coffee granules,” Giovanna tells me.

Metal Filters

Another option is using stainless steel mesh filters for some brewing methods, such as pour over drippers and the AeroPress.

Cinthia only offers the metal filter AeroPress at Astronauta. She tells me that this provides a new experience, even for customers that are familiar with traditional paper filter AeroPress coffee. She also brews with a stainless steel filter in a dripper. 

“Our coffee shop motto is ‘explore your senses’,” Cinthia tells me. “So, we want the client to explore, to taste different coffee styles, different methods… including experiencing coffee from a non-disposable and reusable brewing method.”

“When we brew with metal filters, we often tell the customer about how metal filters don’t absorb the oils in coffee in the same way that paper does. This adds something that is very subtle.”

Cinthia shared both of her recipes with us:

AeroPress (Metal Filter)

• Brew an AeroPress in the inverted style using 15g of medium ground coffee and 180ml water
• Wet your coffee with 50ml water and allow 30 seconds of preinfusion
• Pour the rest of the water in, stir three times, and steep for up to two minutes
• Close the AeroPress, turn it, and press to brew

Pour Over (Metal Filter)

• Brew 18g of medium-fine ground coffee (slightly finer than you would for a paper filter) to 180ml water
• Bloom with 50ml of coffee for 30 seconds
• Pour up to 140ml total (pouring in circles for a cone dripper, or zig-zags for a flat bottom dripper)
• After 2 minutes, pour your remaining 40ml

Cinthia adds that cleaning the filters right after brewing makes a big difference in keeping the flavour consistent.

Although paper is still by far the most popular option for filters in specialty coffee, metal and cloth offer a different drinking experience as well as being reusable. While they are arguably not as popular today, could we see a rise in popularity as consumption trends change among coffee drinkers?

No matter what the answer is, make sure that if you do brew with cloth or metal, you’re cleaning your equipment thoroughly and regular. By taking good care of your reusable filter, you’ll be able to repeatedly brew great coffee while doing what you can to minimise your carbon footprint.

Enjoyed this? Then read How Can We Minimise Waste in the Coffee Industry?

Some quotes were translated from Portuguese by the author. 

Photo credits: Coraa Photography, Fabrikafe, Ana Paula Rosas, Chris Flores, Vee Satayamas

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