Knowing how to use a coffee plunger is an easy way to bring your office coffee to a new level without investing in expensive equipment. For workplaces that want to keep things simple, you don’t need to rely on instant coffee. A French press delivers a richer, fuller-bodied brew that can significantly improve the daily coffee experience for employees and visitors alike. With just a few simple tools and around four minutes, you can brew cafe-quality coffee that’s perfect for meetings, shared kitchens or smaller offices.
The team at Corporate Coffee has put together a guide to help you learn how to make French press coffee properly. Below, we cover everything you need to know, from the ideal coffee plunger ratio to the best grind size and brew time.
What is a Coffee Plunger?
A coffee plunger is a manual brewing system that steeps ground coffee in hot water before separating the grounds with a metal mesh filter. Think of it as similar to tea, but for coffee. Around the world, it’s commonly known as a French press or cafetiere, while South Africans simply call it a coffee plunger. It’s loved for producing a smooth, full-flavoured coffee without needing electricity or complicated equipment.
Coffee is becoming increasingly important in workplaces. From improving the benefits of coffee on focus to supporting better workplace culture, many businesses aim to cultivate a quality coffee service that makes a noticeable difference to the employee experience. Because it’s a priority, having something simple and accessible for everyone to make, like a plunger coffee, can be a great start for any office.
What You Need Before You Start
Before you begin brewing, gather a few essentials:
- A coffee plunger (of course)
- Coarsely ground coffee
- Freshly boiled water
- A timer
- A spoon for stirring
- A digital scale (optional, but recommended for consistency)
The best coffee for plunger brewing is freshly roasted whole beans that are ground just before brewing, although good-quality pre-ground coarse coffee also works well.
How to Make Coffee with a Plunger: Step-by-Step
Making delicious plunger coffee in your office kitchen is really quite straightforward once you understand the basics. Follow these steps:
1. Preheat the coffee plunger
Fill the empty plunger with hot water and leave it for around 30 seconds before emptying it. This heats up the container and helps maintain a consistent brewing temperature and keeps your coffee hotter for longer.
2. Measure your coffee
Add your coffee using the recommended coffee plunger ratio (check the section below). A good starting point is around 60 grams per litre of water, or roughly one tablespoon for every 100ml of water.
3. Add hot water
Pour water that has cooled slightly after boiling over the coffee grounds. Aim for around 93 to 96°C, as boiling water can scorch the coffee and create unwanted bitterness.
4. Stir gently
Give the coffee a gentle stir to make sure all the grounds become evenly saturated. This helps produce a more balanced extraction.
5. Place the lid on and wait
Position the lid on top with the plunger pulled fully upwards. Allow the coffee to steep for around four minutes.
6. Press the plunger slowly
Push the plunger down using steady, gentle pressure. Avoid forcing it, as pressing too quickly can disturb the grounds and create extra sediment. It should glide smoothly, but there should be some resistance to the push.
7. Pour immediately
Once you’ve pressed the plunger, pour the coffee straight into your mug or serving jug. Leaving coffee sitting in the plunger allows it to continue extracting, making it increasingly bitter.
Coffee Plunger Ratio: How Much Coffee to Use
Getting the ratio right makes all the difference. As a rule of thumb, you want about 6g of coffee per 100ml. Everyone’s taste is slightly different, so don’t be afraid to adjust the amount until you find your ideal strength. Here’s a table with some more proportions to go off:
| Cups | Water | Coffee |
| 1 cup | 250ml | 15g (about 2½ tbsp) |
| 2 cups | 500ml | 30g (about 5 tbsp) |
| 4 cups | 1 litre | 60g (about 10 tbsp) |
Grind Size for a Coffee Plunger
Your coffee plunger grind size should look like coarse sea salt. You want a coarse grind because it allows the coffee to extract slowly while preventing fine particles from passing through the metal filter. If the grind is too fine, you’ll likely end up with a bitter coffee and plenty of sludge in your cup. While pre-ground coarse coffee is convenient, freshly grinding your beans usually delivers a noticeably fresher flavour.
How Long Should You Leave a Coffee Plunger?
The ideal French press brew time is around four minutes. Brewing for less time can give you a lighter-bodied coffee that may taste under-extracted, while brewing for much longer often results in bitterness. After pressing the plunger, pour your coffee immediately instead of leaving it sitting in the jug, as the grounds continue extracting even after they’re separated.
Common Mistakes (and How to Fix Them)
My plunger coffee tastes bitter
This is usually caused by coffee that’s ground too finely or brewed for too long. Start by using a coarser grind, then shorten the brewing time slightly if needed.
My plunger coffee tastes weak or watery
A weak cup usually means there isn’t enough coffee or the grind is too coarse. Increase your ratio slightly to around 7g per 100ml of water or try a slightly finer grind (but still relatively coarse).
My coffee has lots of sludge or grit
Fine coffee particles often slip through the mesh filter. Use a coarser grind, allow the coffee to settle for around 30 seconds before plunging, and press slowly to minimise sediment.
My coffee cools down too quickly
Always preheat your coffee plunger before brewing. Warming both the plunger and your mug helps maintain temperature throughout the brewing process.
Just One Part of a Premium Office Coffee Set Up
A coffee plunger is perfect for everyday brewing, but it’s only one way to enjoy great coffee. Some people eventually move to a capsule machine or a commercial coffee machine for larger offices or entertaining, while big workplaces often rely on espresso coffee machines for speed and consistency. Others, like hospitals and industrial facilities, prefer the convenience of an automatic coffee system.
Exploring different brewing methods is part of the fun, whether you’re attending a coffee tasting, comparing different coffee brands, or discovering a new favourite roast. If you enjoy the flavour but want less caffeine, decaf coffee is also an excellent option.
But still, if you prefer the ease and taste, using a coffee plunger is one of the simplest and most rewarding ways to brew fresh coffee in the office. Once you’ve mastered the right ratio, grind size and brewing time, you’ll be able to enjoy consistently delicious coffee in just a few minutes. If you’re choosing an office coffee machine, get in touch with the team to talk about options that will suit you best.
Frequently Asked Questions
Coffee Plunger vs French Press: Are They the Same?
Yes. If you’re making the coffee plunger vs French press comparison, there’s no need! They’re the same thing. “Coffee plunger” is the term commonly used here in South Africa and places like Australia and New Zealand, while “French press” and “cafetiere” are more common internationally.
Can I use pre-ground coffee in a coffee plunger?
Yes. Just make sure it’s a coarse grind designed for French press brewing. Freshly ground beans generally produce better flavour, but quality pre-ground coffee is still a great option.
Can I use boiling water?
It’s best to wait around 30 seconds after boiling before pouring the water. Water that’s slightly cooler extracts the coffee more evenly and reduces bitterness.
Why is my plunger hard to push down?
This usually means the coffee has been ground too finely. Switch to a coarser grind and avoid forcing the plunger.
Can I leave coffee in the plunger after brewing?
No. Pour it immediately after pressing. Leaving the coffee in contact with the grounds causes over-extraction and bitterness.
Can I make tea in a French press?
Yes. A French press works well for brewing loose-leaf tea, although it’s worth cleaning it thoroughly afterwards to avoid transferring flavours between tea and coffee.
What’s the best coffee for a plunger?
Medium and medium-dark roasted specialty coffee beans are popular choices because they produce a balanced, full-bodied cup. Ultimately, the best coffee comes down to your personal taste preferences.
