Dirty portafilters and baskets can also cause coffee to taste ashy and bitter if not cleaned properly. You should regularly clean these parts during service. Give them a good soak in hot soapy water at the end of the day, before scrubbing, rinsing and putting back into the machine.
Like any machine, coffee makers need maintenance. And that means regular cleaning, which is essential for several reasons. Coffee leaves a residue, and the mineral build-up is a haven for bacteria, yeast, and mold. Coffee gunk can make your coffee taste bitter, rendering that Premium Roast undrinkable!
If your machine is left alone without cleaning, that residue will have a few undesirable effects on your coffee: Your coffee will begin to taste bitter. Your coffee and coffee machine will produce an acrid smell.
The coffee residue can build up fast if you don't regularly clean your machine. Dirty residue can make your fresh brew taste bitter and blocked water flow can cause uneven extraction. If you notice a metallic or astringent taste in your coffee, dirty equipment might be the reason.
Your Grind is Too Big/Small
Well, coffee grounds need to be soluble enough to impart good flavor but insoluble enough to stay out of your filter system. If your coffee tastes weak or sour, your drink may be under-extracted. The bad taste comes from the acids in the bean dissolving early in the brewing process.
Watery coffee is mainly the result of under-extraction. It means you didn't extract enough flavors from the grounds to give your coffee life during the brewing process. But remember that this can also be caused by various factors such as not using enough coffee to brew, using a wrong grind size, water temperature, etc.
If your coffee is bitter-tasting, it means you dissolved more organic compounds and flavors than desired. As we now know, this is called over extraction.
As a rule of thumb, espresso that's weak or sour means the grounds were too coarse, while bitter and somewhat chalky coffee suggests you took the grinding process a little too far.
When you drink the coffee, you taste all of the different flavour compounds at once, whereas when you smell it, you experience them in a different composition and some won't be present at all. The dominant taste in coffee is bitter.
Signs It's Time to Clean Your Coffee Maker
So, if your coffee maker is visibly dirty — think water spots, coffee stains, or loose grounds scattered around — it's time for a cleaning, and doubly so if you can't remember the last time you gave it a good scrub.
Part of cleaning your espresso machine is descaling. Descaling your machine cleans it, but it also removes mineral buildup in the hot water tanks. If mineral buildup goes unchecked, it can affect water flow and pressure in your machine. This, in turn, will affect the flavour of your espresso.
What happens if you don't clean your coffee maker? If you don't clean your coffee maker, coffee residue and limescale will buildup inside it. Both will make your machine less efficient in terms of running – there are likely to be clogs – and the taste of your coffee will be affected, too.
Over-extraction, steeping for too long, or using boiling water with brewing methods such as a French press, can result in a burnt coffee taste. Keep the water temperature around 195-205°F (90-96°C) using a thermometer for a more balanced taste.
Your coffee might taste different due to differences in the grind. Refrain from grinding your coffee too finely, otherwise, you are risking over-extracting and exposing your coffee. If you want your coffee to taste the same without any added bitterness, it's essential that you use the correct grinding level.
The temperature of the water used during extraction is a major factor in influencing how bitter (over-cooked) or weak the coffee will taste. Weak coffee can be a result of using water that has cooled too much. The ideal coffee brewing water temperature is around 195-205 degrees or about ~30 seconds off of the boil.
The reason why your coffee tastes bitter, rancid, sour & "you name it!" after 20 minutes is because of Oxidation. Just imagine all your delightful and delicious acids, aromats and oils flavour compounds rotting away to horrible stale tasting compounds.
Old grounds and oils stuck in the portafilter and group head will destroy your espresso's flavor. This is why it's important to clean your espresso machine after every use - and then some.
An over-extracted brew will taste bitter, as the compounds that create sweetness and acidity will be overwhelmed.
Just as coffee beans go rancid after about two weeks, brewed coffee can start to taste bad after about 30 minutes, or the time it takes for the coffee to cool. Then you have about a 4-hour window before the oils in the coffee start to go bad, which further alters the taste.
If you are asking yourself why is my espresso bitter then consider the grind size. A bitter taste comes when the grind size is too fine and too much extraction of the coffee oils happens. Try making your coffee grinds coarser so that the water is not so restricted.
Long, lingering aftertaste often accompanies bitterness, while a quick and dry aftertaste often walks hand-in-hand with sour. Coffee Maker Your coffee maker can also play a role in your coffee taste. One coffee bean blend might taste great brewed with a French press but taste differently if you use an espresso machine.
An overly bitter and sometimes even burned taste can occur when coffee is over-extracted. The most common reason this happens is that the coffee grind is too fine. Under-extracted coffee is often the cause of a weak and flavorless brew. Under-extraction can occur if your coffee is ground too coarsely and/or unevenly.
Over-cooking your coffee is one of the most common reasons your brew tastes bitter. Much like tea, coffee gets its flavor from steeping in hot water. If you let it steep for too long, too much of the bitter flavors come through and your coffee will taste burnt.
Tap water in most parts of the world just isn't suited for coffee brewing. Even if it's clean and potable, it can still be very high in calcium and bicarbonates. And oftentimes, there will be nasty tasting compounds as well.