Why is my coffee machine making watery coffee?

Be across these reasons to make sure you're never a victim of underwhelming coffee again.
Coffee machine
20 March 2023

Why is my coffee machine making watery coffee?

Here’s a horror story for you: Pouring a shot of much needed coffee only for it to come out…watery. The worst bit? It happens more often than you’d think. Repeat after us: No one deserves a watery cup of coffee. 🔊

Luckily, we've got a few facts to get across so you're never a victim to underwhelming coffee:

Your first culprit - the water: 💦

Quality of water plays a huge role in the quality of coffee produced – funnily enough, lots of people don’t know this. 😖

The more magnesium present in the water, the harder it becomes. Higher magnesium levels also bring out the full earthy tones of coffee beans. On the contrary, the bicarbonates in soft water can take a low-acidity coffee roast to a sour taste, significantly altering the taste.

Here's another fun fact: hard water scale is not only extremely harmful to the lifespan of your machine, it's also highly likely to give your espresso machine a very questionable flavour that, well, let's just say...you really don't want. Regular descaling plays a vital role in looking after your machine (and in saving on those maintenance costs). Find the full range of Cafetto Descalers here.

Brewing: ☕

The correct coffee brewing time is what results in optimal extraction, which is what gives you that rich, quality coffee.

Before you begin brewing, it's a good idea to quickly turn your attention to the cleanliness of your coffee machine's shower screen. Why? If it's not clean, you're likely to have coffee oils built up in the screen that can impede the water flow, and in result, give you an extremely underwhelming coffee. We recommend using a combination of Cafetto Espresso Clean and Cafetto Swivel Head Cleaning Brush to clean and brush the group head, shower screen and around the group seal to remove coffee grounds and keep your machine sparkling clean.

Besides having an incorrect tamping pressure impeding an even water flow, a viable reason why your coffee is coming out watery is more than likely linked to the timing involved with the brewing process. If you don't allow for enough time in the brewing process, this will lead to too little extraction.

Arguably the most common reason for weak coffee is not enough coffee grounds used for brewing. Too short of a brewing time is a result of not enough contact between water and coffee grounds (AKA - under-extraction). On the contrary, too much contact between the two variables leads to an over-extraction.

How can I differentiate between the two?

Under extraction will taste sour and lack the sweetness whilst over-extraction will give you an overwhelming bitter taste as the compounds needed to create the sweetness and acidity will be exhausted.

The solution? In general coffee, the brewing time is dependant on the brewing method and size of coffee grinds.

Grind size and dosing: 📏

We've got news for you, and size does matter. Your coffee grind size should not be a sub-par consideration. Controlling this variable seriously impacts how your coffee will taste.

As we've already touched on, the objective with any sort of coffee making is to achieve controlled extraction.

Larger/coarser coffee grounds have less surface area than those that are finely ground. As a result, they allow for more freely flowing water and don't give up their flavour as quick. On the contrast, finer coffee grounds have greater surface area and a much slower flow-through of water. So we've got:

✅ Larger grounds = free flowing water

✅ Finer grounds = slower flowing water

Here is your biggest takeaway point: Your coffee ground should be finely ground, but not so fine that your machine is in struggle town when trying to push water through the portafilter. If your ground is too coarse, you can place bets on the fact that you'll end up with a weak and bitter cup that lacks all the rich goodness you're after - and that is a big fat no from us. 🙅

Once you've put a big tick next to 'grind', it's time to move over to dosing. A simple but very important process of measuring out the right amount of coffee grinds needed to fill your basket. What could go wrong?

Under-dosing and over-dosing. Here's what happens when you get one or the other: Under-dosing prevents the coffee from staying tight and compressed, making the water flow through waaay too fast, which means you're missing out on the full flavour profile the coffee has to offer! Over-dosing, on the other hand, is a fantastic way to eliminate proper water flow - not ideal, at all. It's all about nailing that happy medium to make sure your shot consistency is just right.

We'll throw in another one for you: the machine may need some more attention! Speaking of which, here's some products that do exactly that: www.cafetto.com/products 👈

Now that you've got your 3 ticks in creating the perfect coffee shot, it's only right that you treat yourself to one!