If your morning coffee tastes more like a metallic penny than a rich and smooth cup of joe, you may be wondering why it's so metallic. In this blog post, we'll decode the issue and explore the possible causes, from contaminated equipment to water quality. Get ready to discover how to fix this unpleasant coffee issue and enjoy a delicious cup of coffee again!

Causes of Metallic Taste in Coffee

Low-Quality Coffee Beans

One reason your coffee might have a metallic taste is the use of low-quality coffee beans. Poorly roasted coffee beans can result in a bad roast, leading to a bitter taste and even a metallic flavor. Light roast beans from the grocery store may not have been roasted sufficiently, contributing to the unpleasant taste. To ensure a great coffee experience, try using high-quality coffee beans from a reputable source.

Water Quality

The quality of water used to brew your coffee can also contribute to a metallic taste. Hard water, which contains a high mineral content, can cause a buildup of minerals in your coffee machine, leading to a metallic taste. Additionally, water containing high levels of iron, lead, aluminum, or copper can contribute to metallic flavors. It is recommended to use filtered or distilled water to brew your coffee, or to invest in a water filtration system to avoid this issue.

Coffee Machine and Grinder Issues

Your coffee machine and grinder can also play a role in the metallic taste of your coffee. Over time, coffee machines can accumulate limescale and other impurities, which can impact the taste of your brewed coffee. Additionally, the grinder may be set to a setting that is too fine, causing over-extraction of the coffee.

To prevent your coffee from tasting metallic, regularly clean your machine and grinder, and adjust the grind of your coffee if necessary. It can also help to use non-leaching materials, like glass or ceramic, instead of metal when possible.

Temperature and Brewing Factors

Temperature and brewing factors can also lead to a metallic taste in coffee. The optimal water temperature for brewing coffee is between 195°F and 205°F (90°C and 96°C). Overheating or underheating the water can result in poor extraction, which can cause a metallic flavor.

Moreover, consider the coffee-to-water ratio and the brewing method. Too much coffee, or brewing for too long, can lead to over-extraction and a metallic taste. Cold brew coffee, for example, should be brewed with a lower coffee-to-water ratio than other methods.

In conclusion, to avoid experiencing a metallic taste in your coffee, make sure you use high-quality coffee beans, proper water quality, and well-maintained equipment. Additionally, pay attention to brewing temperature and methods to achieve the perfect cup of coffee every time.

Health-Related Factors Affecting Coffee Taste


Certain medications can alter an individual's taste perception, causing coffee to taste metallic. Blood pressure medications, cancer treatments, and even some allergy medications can lead to a change in the way coffee tastes. It's important to be aware of any possible side effects that medications may have on taste perception and consult a doctor if changes persist.

Medical Conditions

Some underlying medical conditions can also cause coffee to taste like metal. For instance, individuals with liver or kidney problems may experience a metallic taste due to high levels of urea and other substances in their body. If the metallic taste accompanies other symptoms, it's important to consult a healthcare professional to rule out the possibility of an underlying issue. Additionally, people with undiagnosed diabetes or certain cancers might experience a metallic taste in their mouth, but these conditions are usually accompanied by other symptoms.

Oral Health Issues

Poor oral hygiene can contribute to a metallic taste in coffee. Infections, tooth decay, and gum disease can all lead to unpleasant changes in taste perception. Maintaining good oral hygiene and regular dental checkups can help prevent oral health issues that may affect the taste of coffee. Furthermore, individuals experiencing a metallic taste due to oral health problems should consult their dentist for diagnosis and treatment.

Solutions to Improve Coffee Taste

Choose High-Quality Coffee Beans

One of the primary factors in the flavor of your coffee is the quality of the coffee beans themselves. Lower quality beans can lead to a metallic coffee taste. To avoid this, always opt for high-quality, whole beans from reputable sources. The freshness of the coffee beans is also crucial, so be sure to check the roast date and store them in an airtight container.

Check and Improve Water Quality

The water source used for brewing plays a vital role in the overall taste and flavor of your coffee. Hard water, or water with high levels of calcium and magnesium, can cause a metallic coffee taste. To improve your coffee's taste, consider using filtered or bottled water instead of tap water. This will help eliminate any unwanted minerals that can affect the taste and quality of your coffee.

Clean and Maintain Coffee Equipment

A dirty coffee maker or espresso machine can accumulate mineral deposits and leftover coffee oils, which can cause a metallic taste in your brewed coffee. Regular cleaning and maintenance of your coffee equipment are essential to avoid these issues. Descale your machine regularly using a commercial descaling solution or a homemade vinegar solution to remove limescale buildup. Additionally, clean your coffee grinder thoroughly to prevent the metal blades from heating up and contributing to the metallic taste.

Equipment Cleaning Method
Coffee Maker Descale regularly with vinegar or commercial descaling solution
Espresso Machine Perform backflushing and descaling procedures as necessary
Coffee Grinder Disassemble and clean blades, burr, and other components

Adjust Brewing Temperature and Time

Both the brewing temperature and time can significantly influence the flavor of your coffee. Brewing at too high a temperature or for extended periods can cause over-extraction, leading to a bitter and metallic taste. To avoid this, use a thermometer to ensure your water is at the ideal temperature (195-205°F) and adjust the grind size based on your preferred brewing method. For example, a finer grind is suitable for espresso, while a coarser grind works best for drip coffee or French press. Experiment with brewing times, too; under-extraction can also produce a metallic or weak flavor.

In conclusion, improving your coffee's taste by eliminating the metallic flavor involves choosing high-quality coffee beans, using filtered or bottled water, regularly cleaning and maintaining your coffee equipment, and adjusting your brewing temperature and time. By making these changes, you can enjoy a better-tasting cup of coffee every day.

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Tony Barlow

Tony Barlow

Majesty Coffee Technical Sales Expert - Meet the Team

Tony Barlow, with over a decade of experience in the coffee industry, is the go-to technical sales expert at Majesty Coffee. He's passionate about helping businesses find the right espresso equipment for their needs.

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