After the recommended vinegar cleaning the coffee tastes bitter and terrible. What can be used to get the original good flavor back.

two days is not enough for the machine to scale or get dirty from old grinds usually would be either coffee or water problem ---but depending on machine you have didnt specify- can be residue from plastic or container try running a vinegar cleanse than 3 just fresh water then try a coffee drop and see it taste is any different if no change bring back for a refund or exchange

What are you using for water? If you are just using tap water try buying a bottle of distilled water at the grocery store. Tap water - especially if it has Chlorine in it - makes terrible tasting coffee. Plus I'd suggest it's not good for you anyway.

You can also try the manufacturer's cleaning recommendation which typically involved running a water/vinegar mixture through the unit and then a couple of empty pots of plain water.

Last thing to check is to replace the water filter in the coffee maker if the model you have has one. Some higher end models do.

Good luck.

If the water that comes into contact with the coffee grounds is too hot, you will extract bitter elements from the coffee. The water should not be boiling when poured on the coffee grounds. Coffee oils, fats and sediment are the natural parts of the coffee bean that causes bitterness by forming as the brew ages. The longer the coffee sits the stronger it tastes.
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Bitterness is a dominant quality in the overall taste of coffee. You need a certain amount of bitterness to balance out the flavor. There are two types of chemicals that give coffee most of its bitter taste - both are antioxidants.

Debris was left in the chamber when manufacturing the unit. Flus and clean accordingly and it will survice.

If you are using a Claris filter, please remove this from the watertank. The descaling agent will clog the filter and make the water taste bad. After descaling, also be sure to rinse the watertank so there`s no resedue of the solvent left in the tank.

However, bitter taste on the coffe usually is related to the coffee side; Try to run a cleaning program. And check grinder settings. If the powder is to fine, it will increase the contact time, and that will make the coffee bitter. My advise is to clean the machine and experiment a little with the grinder settings.

Good luck!

You need to delime or descale the unit with white vinegar, that will clean it out

Go here to get the manual and it will tell you how to do it....

http://www.retrevo.com/support/Delonghi-EAM3500-Coffee-Makers-manual/id/3878ci577/t/2/

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/sean_54c3a3dc48a7773c

mcdevito75 here, Contact Bunn for their recommended cleaning material for your coffee maker, or see any large store that carries coffee makers for their cleaning kits.

I would check the temperature of water. Sounds like it might be too hot. The temp of the water should be between 192 and 197. Colder and its sour, and hotter and its bitter.

The quality of the water is responsible for the flavor of the coffee. If you have had this coffee maker for a while it is probably coated with lime. Run a couple of cups of vinegar through it followed by a couple of pots of clear water. That will clean up your machine.

Once it is clean, try making a pot with bottled water, or water that you run through a water filtering pitcher.
You will be amazed at the differenct.