It doesn't need to be that way but Moka pot coffee can taste burnt, even with medium roasts. Assuming you're not using an overly dark roast, this can happen for a few reasons: The collector chamber is too hot when the coffee pours over it Coffee grounds spend too much time inside the filter basket and burn before and during the brewing process Not filling the bottom chamber to the required level. The valve is the appropriate measure and it's important to consider it when making coffee with your Moka pot. If you aren't sure about the best way to prepare Moka pot coffee, you can read our guide. We tell you all the steps you need to brew a perfect cup of coffee, free of burnt taste and undesirable bitterness!