Vietnamese Phin Brewing

What a phin is and how its parts work

A phin is a Vietnamese metal coffee brewer that sits directly on a cup or glass. Water passes through the grounds and perforated metal under gravity, without a paper filter or a pump.

Most designs have four main parts:

• Filter plate: the wide base that rests on the cup.
• Brewing chamber: the cylinder holding the coffee and water, with a perforated bottom.
• Press or insert: a perforated disc resting on the grounds.
• Lid: the cover for brewing, which can also serve as a drip-catching stand afterwards.

There are two common insert designs. A gravity insert rests freely on the coffee; a screw-down insert attaches to a central thread and allows its tightness to be adjusted.

For your first attempts, let a gravity insert settle under its own weight. With a screw-down version, follow its maker’s instructions and avoid compressing the bed hard: the coffee needs room to become wet and expand.

The phin belongs among gravity-fed brewing methods, but its concentrated recipes deserve their own approach. Do not assume that a familiar filter-coffee recipe will suit it unchanged.

Choose your coffee, dose and grind

A Vietnamese robusta or robusta-arabica blend is a useful starting point, particularly if you want to add condensed milk. Vietnamese roasters also offer arabica for phin brewing, so robusta is not a requirement imposed by the equipment.

Choose a coffee whose description appeals to you rather than treating “Vietnamese” as a single flavour. For a milk drink, a roast described as chocolatey, nutty or dark-roasted is a sensible place to begin.

A starting recipe, not a universal standard

For a small, single-serving phin, use this editorial starting recipe:

This adapts published manufacturer guidance into a weighed, metric method. It is not an SCA phin standard, and it is deliberately less concentrated than some Vietnamese iced-coffee recipes.

The water figure is input water, not finished drink volume. Do not keep topping up until the cup contains 120 ml: that would be a different recipe.

Start with a fine, sand-like grind. Grinder labels are not consistent, so judge the setting by how the coffee flows through your brewer rather than by a number borrowed from someone else’s grinder.

If the brew rushes through, try a little finer. If it barely moves, try coarser before changing the dose, temperature and insert pressure as well.

Vietnamese phin brewing: step by step

You need a small phin, a stable heatproof cup or glass, scales, a kettle and a timer. Have a spoon ready if using condensed milk.

The following method makes one small coffee. The condensed milk is optional.

1. Check and warm the equipment.
   Make sure the plate sits securely on your cup. Rinse the phin and cup with hot water, discard that water and dry the chamber before adding coffee.

2. Add condensed milk if wanted.
   Put 25 g of sweetened condensed milk in the cup. This is a starting amount drawn from a published Vietnamese iced-coffee recipe, not a compulsory proportion.

3. Weigh and level the coffee.
   Add 14 g of ground coffee to the chamber. Gently shake it level rather than leaving a mound on one side, then place the gravity insert on top without forceful tamping.

4. Bloom for 45 seconds.
   Start the timer and gently pour 30 g of water at 94°C, approximately 30 ml before heating, over the insert. Wait 45 seconds before adding the remaining water.

5. Complete the water addition.
   Slowly add another 90 g of water, approximately 90 ml before heating, bringing the total to 120 g. Pour gently over the insert and fit the lid; if the chamber cannot safely accommodate the water, pause rather than filling it to overflowing.

6. Let it drip without pressing.
   As a manufacturer’s diagnostic guide, look for the first drip by about 2 minutes and the last main drips around 5 minutes, measured from the first water addition. These are reference points, not a pass-or-fail test.

7. Remove, stir and taste.
   Carefully lift the hot phin onto a heatproof surface once the main dripping has finished. Stir thoroughly if using condensed milk, then taste before deciding what to change next time.

Record the coffee, grind setting, water amount and finish time. A short note such as “too intense, flow steady” is more useful than chasing an exact time without tasting.

Why the bloom matters

The bloom is the initial wetting stage, when hot water causes trapped carbon dioxide to escape from the grounds. You may see swelling or bubbles beneath and around the insert.

The pause gives the coffee time to wet before the chamber receives the remaining water. Do not press the insert down to suppress the swelling.

Manufacturer instructions differ here. Nguyen Coffee Supply’s main brewing guide places the gravity insert on the dry grounds, while its maintenance guide also suggests blooming before fitting the insert when gas causes problems.

Use the insert-first method above for consistency. If it repeatedly lifts or tilts during blooming, try blooming without it, then gently fit it before the main pour.

Condensed milk and the iced version

Sweetened condensed milk is a traditional partner for Vietnamese phin coffee. It brings sweetness and thickness, but it is an accompaniment rather than a requirement of the brewing method: black phin coffee is also an option.

Make cà phê sữa đá

For cà phê sữa đá, Vietnamese iced milk coffee, brew into the condensed milk using the method above. Remove the phin, stir until the milk is fully mixed through, then add ice.

Taste after stirring and cooling. If you want less sweetness next time, reduce the condensed milk rather than changing the coffee recipe at the same time.

For a more concentrated iced drink, PHIN Coffee publishes a stronger recipe using 20 to 25 g of coffee and roughly 80 to 100 g of water. Treat that as a separate recipe and check that the dose suits your chamber, rather than forcing extra grounds into a small phin.

Handle opened milk properly

Follow the condensed milk’s instructions for refrigeration and use after opening. Transfer unused milk from an opened tin into a clean, covered storage container rather than storing it in the tin.

Food Standards Agency guidance recommends a fridge temperature of 0 to 5°C. Return the milk promptly after preparing your drink; do not assume that an opened product can be stored like a sealed tin.

Troubleshooting the slow drip

Change one variable per brew wherever possible. Grind is usually the clearest first adjustment because both excessively fast and stalled flow can result from an unsuitable grind.

For a stalled brew, do not push down on the insert or shake a chamber full of hot water. Let it cool before dismantling it.

A slightly faster or slower finish is not automatically a fault. Manufacturer guidance explicitly allows variation, and a cup you enjoy matters more than a stopwatch reading.

Understanding strength, extraction and water

Strength describes the concentration of dissolved coffee in the drink. Extraction describes how much soluble material has been removed from the grounds. They are related, but they are not interchangeable.

Adding hot water after brewing reduces concentration without sending more water through the coffee bed. This makes it a useful first experiment when a cup tastes pleasing but feels too intense.

Grinding finer is a different intervention: it changes the particles and the routes water can take through the bed. Peer-reviewed mathematical modelling, compared with experimental coffee-bed data, shows that flow patterns can produce uneven extraction. This is supporting mechanism research, not a controlled trial establishing the best phin recipe.

The practical lesson is modest: finer is not automatically better. Aim for repeatable flow and an enjoyable cup, not the slowest possible drip.

The SCA’s older published water guidance specifies clean, odour-free water without chlorine. That is a useful starting principle, but do not import its conventional filter-coffee strength targets into this concentrated method.

Keep your water source consistent while adjusting grind. If investigating local hardness, consult your water supplier’s report rather than assuming that all UK tap water is alike.

For a different way to manage contact time, explore steep-and-release brewers. To compare this method with another traditional preparation, read about Turkish coffee brewing.

Cleaning and keeping the method repeatable

Once the phin has cooled, remove the grounds and wash the separate parts. Inspect the perforations and rinse away trapped particles.

Use a soft sponge rather than steel wool or an abrasive scourer. Check your own brewer’s care instructions before putting it in a dishwasher, since a manufacturer’s dishwasher claim does not apply automatically to every phin.

Before the next brew, check that the insert sits properly and the plate remains stable on the cup. Consistent preparation makes a grind adjustment much easier to judge.