Why is my coffee bitter, sour or burnt?

Sometimes in the morning it’s hard enough to find your wallet, keys and phone, let alone try to troubleshoot a coffee that just tastes off. We’ve all experienced a brew tasting bitter, sour or burnt, but it doesn’t have to ruin your day. These problems can often be fixed with a quick adjustment and re-brew, provided that the problem is not the coffee beans themselves.

Espresso coffee tastes best when made with medium-roast beans. Beans that are too fresh can taste sour, as they haven’t had time to degas. From about a week after roasting your coffee will have settled in and will be beautiful for espresso based coffees.

Assuming you have great quality coffee beans and they aren’t too fresh, this guide will help you solve some issues with the coffee extraction.

Words to understand

Extraction = This refers to the pour of the coffee from your espresso machine. It’s extracting the coffee oils from the beans.

Blonding = When the coffee pour is a pale yellow colour

Basket = The basket holds the coffee grinds which the water flows through

Crema = The light brown oils that sit atop the coffee shot.

Puck = The coffee grinds that remain in your basket after you have run a shot. The make a shape like a hockey puck when you empty the basket out.

Why does my coffee taste bitter?

What to look for: Your puck will be super soggy and sloppy. A thin white/pale yellow watery pour and spirals at the end. Big patches of white on your crema.

Diagnosis: When your espresso comes out tasting bitter, it usually means that the extraction or pour time is too long. Commonly, you’ll see a pale yellow/white stream of coffee that wobbles and spirals towards the end of the shot.

Remedy: Adjust your brew time. A good pour will be somewhere between 25 – 35 secs. Keep watch on the shot as it comes through and as soon as you see the coffee coming out in a light “blonde” colour, stop the shot immediately. This is almost pure caffeine and caffeine tastes very bitter so you want to avoid this and stop the shot as soon as you see it start blonding. Most people make the mistake of trying to extract too much coffee out of a single coffee dose. If you want a strong coffee, get a bigger basket (22g – 28g) and keep the shot time within the ideal range. Don’t worry, you’ll still get your caffeine fix, it just won’t be as bitter.

Why does my coffee taste sour?

What to look for: The coffee GUSHES out under 15 seconds and is wide, pale yellow and bubbly. Your puck will be really dry and powdery.

Diagnosis: A sour espresso shot is one that is under-extracted; meaning the water has run through the coffee too quickly and hasn’t extracted the delicious tasting oils. You are either not putting enough coffee in your basket or you are tamping too lightly and your coffee is too coarse. If your shot pours in under 15 seconds, you are getting under-extracted coffee. The coffee will appear blonde and pale and bubbly. The coffee crema will also dissipate rapidly and the taste will appear thin and sour.

Remedy: To fix a sour espresso shot, adjust your grind to be finer. This will mean that when you tamp the grinds you’ll create more resistance for the water to pass through allowing it to pick up more oils along the way.

Why does my coffee taste burnt?

What to look for: Slow dripping for almost the entirety of the shot. Dark/black pours. You only get a small volume of coffee liquid even after a 45 second extraction. Your puck will look soggy and sloppy again.

Diagnosis: Burnt tasting espresso has been over extracted, meaning the hot water is flowing through the grinds too slowly creating harsh and burnt tasting espresso. You coffee grind is too fine or you are over filling the basket and tamping the coffee too much.

Remedy: To remedy a burnt tasting espresso shot, adjust your grinder to a slightly coarser grind. This will help the water to seep through the grind more evenly without too much resistance, and it won’t overcook the coffee.

If you try out any of these fixes and they don’t work, leave us a reply and we’ll try and give you specific and detailed help! No one has time for dodgy tasting coffee.

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