The Phin Filter: Vietnam's Coffee Maker

What is the Phin Filter?

The phin filter is the traditional method of brewing coffee in Vietnam. It is made of stainless steel or aluminum, much like a moka pot, but is much thinner and lighter. It is also frequently referred to as a “Vietnamese coffee press” or "Vietnamese coffee maker." 

It consists of four essential parts:

1. The brewing chamber, which is where the coffee and water go;
2. The gravity press, which goes on top of the coffee grinds (there are different types of presses, which we’ll see below);
3. The filter plate, which works by letting you place on top of a cup, mug or even carafe;
4. And lastly, the filter lid which goes on top of the brewing chamber and doubles as a coaster after brewing is completed. 

There is, however, more than one single type of phin filter. Let’s explore the differences between different types of phin filters: 

1. Gravity press filter: The press sits on top of the coffee without the aid of any sort of weight or latch, which is why it’s called a gravity press. The gravity press allows gas to escape during coffee brewing, especially when using fresh coffee.
2. Screw-on filter: The press has a screw-on mechanism. It latches to the lower part of the brewing chamber and from there you can screw more or less depending on how tight you want the coffee bed. This type of filter generally works best with pre-ground coffee since it tightly packs the coffee down and controls the speed of the drip. However, the screw-on filter may be trickier to use with freshly ground coffee since it needs room to expand, degas and bloom.

Both types of filter work well to extract and brew coffee grounds. We personally love gravity press filters as they allow gas in freshly roasted coffee to escape more easily during the brew, making for a less hands-on experience while lowering the chances of over-extracting the coffee!

The phin filter has many advantages. One of its distinct advantages is that instead of using a paper filter, it uses a metal filter— which, incidentally, is built-in. Both the brewing chamber and the filter plate act as metal filters. In an industry that produces an inconceivably high quantity of waste, the phin filter stands out for not needing paper filters or even replaceable metal ones.  

The phin filter is also made using either aluminum or stainless steel— both highly recyclable materials. You may find some phin filters that include plastic handles. We make our phin filters with no plastic whatsoever — making the phin filter arguably among the best brewing methods for the environment! 

We’ll go over other advantages of the phin filter later. First, let’s check out its history. 

The History of the Phin Filter

French colonization of Vietnam beginning in the 1880s saw the introduction of many French customs to Vietnam. One of these was the introduction of coffee as a crop— something that had been around for at least two decades before, but it was during this period that it became a serious source of income. 

The French used a French press to make their coffee— but most Vietnamese people did not have access to them. As such, there are indications to show that the phin filter likely originated not in big cities– which were cosmopolitan in every way– but instead in rural areas where coffee was harvested. One indication is the tradition of using condensed milk for sweetening coffee, a widely spread practice in rural Vietnam. 

Condensed milk was widely used by Vietnamese farmers as a means to preserve milk as it greatly extends its shelf life and doubles as dairy and as a sweetener. Nowadays, condensed milk is present in many types of Vietnamese drinks from the famous Vietnamese iced coffee to Vietnamese egg coffee. Out of need came ingenious brew tools and coffee additions that are now iconic.

Coffee most likely went from being a symbol of French rule to a source of national pride after the anti-French revolution— which started in 1946. Coincidentally, this would be when one of Vietnam’s most famous coffee drinks would be invented: the Vietnamese egg coffee. 

Nowadays, the phin filter is the most widely used method for brewing coffee in Vietnam, where incredibly modern coffee shops are not a rare sight. And coffee, robusta in particular, is of great pride as a national product and an important pillar of the economy. 

How Does the Phin Filter Work?

The basic principles of coffee extraction apply to the phin filter. It is most similar to a pour over like the Hario V60 or a French press: ground coffee is poured into the brewing chamber, where it is brewed using hot water. The main difference is that the press is traditionally introduced before pouring the brewing water, as opposed to after. It helps keep the coffee bed in place, which in turn results in a more concentrated brew.

The whole process takes about 6 minutes and it’s completely hands-off. You can simply pour the water and come back in five minutes and your coffee will be waiting for you. Gravity and hot water do their job well with this brew tool!

We recommend brewing your coffee in two steps instead of one. The first pour is for the coffee to bloom, a step that is very important when using fresh coffee as it releases the gases that become trapped inside the coffee beans during the roasting process (the more bubbles you see, the fresher the beans). A gentle bloom is associated with a more balanced taste in coffee, which is why it’s often suggested. The second pour uses the rest of the water to produce the full amount of coffee in your phin filter!

How do I use the Phin Filter?

The phin filter is a great tool for making all sorts of coffee— particularly Vietnamese iced coffee, which has been gaining a lot of popularity in recent years because of how delicious and easy to make it is.

But in reality, the phin filter is a brewing method just like any other. This means that you can have it any way you want: black, with milk, iced, etc. 

Here’s a simple guide for making coffee using a phin filter:

Ingredients:

• 2 tablespoons (~14 grams) of ground coffee
• 4 ounces of hot water

Steps:

1. Heat the water to 205°F. 
2. Add ground robusta (preferably) coffee.
3. Drop in the gravity press and gently push and twist to even out the coffee bed.
4. Pour 0.8-1 ounce of water. Wait for 30 seconds for the coffee to fully bloom.
5. Pour the rest of the water (or simply top it up). 
6. Wait from five minutes for all the coffee to drip down into your cup. 
7. Enjoy however you like!

One important thing to keep in mind when brewing coffee in a phin filter is that the grind size matters immensely if you want to achieve solid results. 

The usual rule of thumb is, when using a grinder, to use a setting that is between medium and fine. Espresso or pour over grind are not quite there— instead, aim for a grind size similar to that of the moka pot; that’s about one to two settings finer than the medium setting in most home coffee grinders.

Brew time should always be between five to six minutes. At around two minutes we should be seeing the first drips of coffee— if this doesn’t happen, it means extraction is taking longer than it should and there’s probably a problem. If the coffee drips sooner, that’s not an issue so long as it doesn’t brew completely within the first two minutes or so.

The most common problem when using a Vietnamese phin filter is the grind size is either too fine or too coarse, which means the water is flowing too fast (under extraction) or taking too long to flow through (over extraction). You want to avoid this by aiming for the 5 minute mark. Another common problem is an uneven coffee bed; water flows off to one side, which can also mean a weaker coffee than usual because the coffee is not equally extracted. To avoid this, stick to the ratio provided above (1 tablespoon of coffee to every 2 ounces of water) and make sure to even the coffee bed every time. 

What Makes the Phin Filter Unique?

Now, let’s discuss the advantages and perks of the phin filter. Every brewing method has its unique perks. Here’s some of our favorite advantages of the phin filter:

• Portability.
  Unlike most brewing methods, the phin filter is extremely portable. It’s made with very resistant materials and yet it’s also quite lightweight and small. It wouldn’t break easily like a French press (usually made of glass) or a ceramic brewing device like the Hario V60. It’s arguably even more portable than the Aeropress! 
• Ease of use.
  The phin filter is straightforward. There aren’t really any complicated parts and not a lot of thinking involved. There isn’t a steep learning curve like there is with other methods; after a couple of tries, you’ll get the hang of it!
• Easy to clean.
  Chores are universally disliked and cleaning your brewing device is the kind of chore that you have to do otherwise it gets dirty in a way that compromises the taste of future cups of coffee or even the integrity of the device. This isn’t really the case with the phin filter, though, because there are hardly any crevices in which debris can get trapped and fester. Rinsing gently with water and soap does the job in most cases. 
• Sustainability.
  As we mentioned earlier, there’s much to be said about the industry of coffee in terms of sustainability. Single-use packaging and paper filter use is rampant with all sorts of brewing methods, which is undeniably bad for the environment. Brewing devices like the phin filter that are made out of stainless steel and that require no single-use filters are a win for the consumer and for the health of the planet!
• Reusability.
  Aluminum and stainless steel, the two most typical materials used to manufacture phin filters, can be reused virtually indefinitely. A good example of this is the moka pot, which is also made of aluminum and can easily last decades brewing as well as the first time— so you can expect your phin filter to last for decades, too. The phin filter is a small investment that will continue to make good coffee for you for decades to come! 
• Versatility.
  Coffee brewed using a phin filter is, no bias, at an optimal level of concentration and intensity. It fits into a sweet spot that makes it viable to make just about any sort of beverage. If you want to make espresso-based drinks with it, you definitely can. If you want something closer to a drip machine, you can make that, too! It’s a great brewing method for those of us who like to have a little bit of everything instead of simply drinking espresso or drip all day. The phin filter, then, becomes an all-purpose coffee brewer with which you can make almost all types of coffee beverages! 

Ultimately, the Vietnamese phin filter is among our favorite brew tools to make coffee and we believe it should be a part of every coffee corner much like your other tools, spoons, and brewers. 

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Learn how to brew fun coffee drinks using Vietnamese coffee here.