6 Sure-Fire Ways To Fix Bitter Cold Brew Coffee

Is your cold brew coffee bitter? Wasn’t it supposed to be less bitter than regular coffee? Yes, it is and it’s one of the key reasons why it’s so popular. If your cold brew is too bitter, there are a few things that could have gone wrong, let’s find out what and how to fix it.

Bitter cold brew coffee often results from coffee grounds being too finely milled, using overly dark roasted beans, and/or steeping the cold brew for too long. However, other factors can also contribute. Employ coarsely ground fresh coffee and experiment with lightly roasted beans to create a less bitter cold brew.

Let’s Dive Deeper into What’s Going Wrong and Explore Other Causes and Solutions for Bitter Cold Brew Coffee.

Understanding the Causes of Bitter Cold Brew Coffee

Using older beans or pre-ground coffee can introduce unusual flavors. Coffee older than two months could lead to bitterness in cold brew.

Bitterness in cold brew coffee often stems from over-extraction of coffee grounds. The bitter compounds in coffee beans are the last to dissolve in water. Over-extraction occurs due to several factors:

  • Insufficient coffee beans for the water quantity: Fewer coffee grounds mean water extracts more at the same time.
  • Too fine coffee grind: Finely ground beans provide more surface area for water to extract coffee grounds, leading to quicker extraction.
  • Extended steeping: Allowing cold brew to steep for too long can lead to bitterness, much like over-steeping tea.
  • Steeping at too high a temperature: On hot summer days, warmer water may lead to quicker extraction.

Moreover, certain beans contain more bitterness than others. Robusta beans tend to taste much more bitter and dark than Arabica beans. There’s also considerable variation within Arabica beans from different regions and qualities. Generally, lower-quality beans are more bitter, while higher-quality ones are less bitter and have a fruitier taste.

Fine coffee grind sizeUse coarsely ground fresh coffee for cold brew
Too dark roasted beansExperiment with lightly roasted beans for a less bitter cold brew
Over-extraction from extended steepingShorten the cold brew steeping time
High steeping temperatureBrew in the refrigerator to slow down extraction
Using older or pre-ground coffeeUse fresh beans (2 to 6 weeks after roasting) and grind beans yourself
Wrong ratioAdjust coffee-to-water ratio, use more coffee/less water for less bitterness.
Beans containing more bitterness (e.g., Robusta)Opt for lighter roasted beans or medium roast beans for a balanced cold brew. Choose Arabica for less bitterness

Solutions for Bitter Cold Brew Coffee

1. Use Fresh, Quality Coffee

The best way to improve your coffee is to use fresh beans. Coffee beans taste best from two weeks to six weeks after roasting. After that period, the flavor declines, and beans are notably less desirable after 8-10 weeks. Pre-ground coffee deteriorates even faster after its vacuum-sealed package is opened.

Purchasing new coffee and attempting a cold brew with it is recommended. Grinding beans yourself is the best option. Whole beans retain freshness longer, and freshly ground beans are superior. Coarsely grind beans for cold brew, and investing in an adjustable coffee grinder will yield much better results than using pre-ground coffee.

Quality beans from a specialty store will also make a significant difference.

2. Use More Coffee

You might have used too few coffee grounds. Cold brew can tolerate this to some extent, but the same ratio as filter coffee won’t work.

Refer to this article to determine if you’re using the right coffee-to-water ratio. If not, or if you’ve never considered it, adjusting the ratio should be your first step in your cold brew recipe.

Weighing coffee and water will ensure the correct ratio.

3. Coarser Grind

For cold brew, a notably coarser grind is vital – much coarser than for filter coffee. Ground coffee for cold brew should be about the size of coarse sea salt or peppercorns.

Due to this, supermarket pre-ground coffee isn’t suitable for cold brew. The pre-ground coffee there is often too fine. Using an adjustable coffee grinder or having your coffee ground at a specialty store is your best option.

A relatively coarse grind is ideal for cold brew.

4. Shorten the Cold Brew Steeping Time

Cold brew coffee can steep from 8 to 24 hours. In the initial 8 hours, most of the caffeine is extracted, but not all of the flavors. After 24 hours, you’ll have extracted all you can from the beans. The most commonly used brewing time for cold brew is 12-18 hours.

The steeping time depends on whether you’re brewing in or out of the refrigerator.

If the above solutions don’t yield desired results, consider shortening the steeping time. Bitter compounds often emerge from coffee grounds last, so stopping earlier will reduce their presence.

Taste a bit of the brew after 8 hours and then every two hours to pinpoint the optimal result.

5. Refrigerate the Cold Brew While Steeping

An alternative to reducing the cold brew’s steeping time is to do it in the refrigerator. Warmer water extracts coffee faster. Although cold brew doesn’t use hot water, there’s still a significant temperature difference between the refrigerator and the ambient temperature, especially on hot summer days.

In the refrigerator, the extraction process slows down. If you want to prepare the coffee well in advance but find it extracts too quickly outside the refrigerator, using the fridge is a viable solution.

When steeping in the refrigerator, it’s essential to use an airtight container. Coffee easily absorbs odors and flavors that circulate in a refrigerator. After steeping, storing the coffee in the fridge is a good idea.

6. Opt for Lighter Roasted Beans

Darker roasted beans taste more bitter. This is due to increased caramelization with darker roasts. Just like with bread, meat, and other baked goods, the darker the roast, the more bitter it becomes. Simultaneously, other flavors in the bean degrade. Lightly roasted beans often offer a fruity, juicy taste that diminishes as roasting darkens.

Additionally, as beans become darker, they also become more porous, making them easier to extract. Therefore, darker beans need shorter steeping times than lighter ones.

For cold brew, using a medium roast is advisable, especially if you’re currently using dark beans that result in overly bitter coffee. Medium-roasted beans provide a balanced cold brew with a blend of bitterness and fruity notes without becoming overly bitter.


Welcome to CoffeeImproved! Since falling in love with coffee, I've been on a journey to improve my morning cup day by day. That means I've tried many different brew methods, beans and equipment and experimented with all of them to find what I like. This is where I share what I've learned with you.

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