What Makes a Perfect Cup of Coffee?

How hard can it be to make a cup of coffee? Just pour hot water over coffee powder, right?

Well sure, you can do that… but there’s so much more to making that cup of perfection. With the right coffee beans and simple equipment, your daily cuppa is instantly elevated. Trust us – it’s worth putting in that extra 5 or so minutes for a fresh brew.

Here are the basics of coffee chemistry that will make you an expert in home brewing. This might just be the start of your home barista adventure.

Use Fresh Coffee Beans

two portafilters, each filled with coffee beans and coffee grounds
Most people buy and use ground coffee for its convenience but they might just be missing out on truly delicious, aromatic coffee. Photo from Zarak Khan

When fresh ingredients are used in cooking, food tastes better – the same goes for coffee.

The first step to discovering the various flavours in coffee is to have access to freshly roasted beans. At the end of the day, the coffee beans used are going to have one of the biggest effects on that brew.

The moment coffee beans are taken out from the roaster, volatile oils that are responsible for creating its flavour will evaporate upon contact with air. What’s more, when coffee is ground into powder, the flavour is muted even quicker.

Always store your beans in an air-tight container, away from sunlight, and consume within 2 weeks to get the best out of its freshly roasted flavour. If the hassle of frequenting the supermarket worries you, try these coffee bean subscriptions in Singapore and Malaysia.

The rule of thumb is to ground your beans just before brewing and ensure that they are ground to a size best suited for your coffee maker.

Using Clean Equipment

espresso being extracted from a coffee machine
Regardless of which coffee maker you use, regular cleaning is necessary to ensure hygiene and a consistent brew. Photo from René Pollock

When was the last time you cleaned your coffee maker?

Just like everything in the house, your coffee maker should be part of your cleaning list or else, run the risk of bitter and funky coffee, plus an off-putting buildup of limescale in your machine.

You don’t need expensive tools or cleaning agents to ensure the hygiene of your coffee gadget. Based on the equipment you are using, there are different ways to clean it.

If you are using a non-electric coffee machine, wash removable parts with dish soap after every use to prevent coffee stains. Wipe down the exterior and leave the reservoir’s lid open to dry after washing – bacteria love moisture!

For automated machines, always refer to your machine’s care manual for instructions on descaling. You can either make your own descaler or purchase a brand-specific one.

Here’s a step-by-step guide on how to descale your machine.

The Science of Water

a man pouring hot water into a filter cup coffee
Water is not just the biggest ingredient in coffee; it can transform the character of a brew. Photo from Jakub Kapusnak

Water has always been the most underrated aspect of coffee brewing.

Many of us will simply boil tap water and pour it into our coffee machines or french press. But in most regions of the world, the mineral content and pH level of tap water have drastic effects on coffee.

According to The Specialty Coffee Association of America, the ideal mineral balance is 150 parts per million (ppm). Coffee produced with water that contains the perfect amount of minerals is balanced and has a smoother finish.

On the other hand, lower mineral content often results in over-extraction and bitterness, whereas higher mineral content will make your brew more sour due to under-extraction.

Is your coffee tasting more sour than usual? Here’s why and how to prevent it.

One way to have access to water that is suitable for coffee is through a household filtration system or bottled spring water.

Too big a commitment? It’s okay if you don’t have a household filtration system and want to avoid over-consuming bottled water. The good news is that a filtered water jug is the next best alternative to extracting the best out of your coffee.

How the Perfect Cup Should Look and Taste Like

Essentially, coffee brewing is the extraction of compounds from the beans.

Some compounds such as acids and sugars are extracted easily. Others take a little longer, like oils and bitter tannins. That’s why under-extracted coffee tastes so underwhelming whereas over-extracted coffee can taste bitter and intense.

Understanding the extraction process will help you to avoid common brewing mistakes. To spot an under-extracted or over-extracted coffee, pay attention to its colour. The infographic below shows it all.

An infographic on what makes a perfect cup of coffee
A handy guide to how a perfect cup of coffee should look and taste like.


Just like how we have different tastes and palates when it comes to food, everyone has a preference with coffee.

The perfect cup of coffee is all about trial-and-error and exploring various beans, roasting techniques, brewing methods and choosing your favourite flavours.

Don’t have the time to perfect your cup of coffee? Create and customise all your recipes with the De’Longhi Prima Donna Elite Experience and enjoy a personal home barista that is always at your service.