Introduction:As summer heat intensifies, iced coffee becomes the go-to choice for beating the heat, and cold brew stands out for its easy preparation and smooth taste. But is cold brew a good match with milk? In fact, as long as you get the coffee-to-water and milk ratios right, you can enjoy an iced milk coffee that combines rich coffee aroma with silky milk flavor. This article delves into the selection of coffee beans, grind size, coffee-to-water ratio, steeping time for cold brew, and how to add fresh milk to achieve the best flavor balance. It also provides time-saving tips for quick preparation using drip bags.

Open your phone’s weather app, and you’ll see temperatures soaring above 30°C—summer has clearly arrived. During these hot days, various refreshing and energizing coffee drinks become a lifesaver for many. Among the many iced coffees, cold brew (also known as cold drip) stands out as a top choice for homemade coffee thanks to its simple steps and gentle taste. Just mix coffee grounds with water before bed, refrigerate overnight, and enjoy it the next day. But some readers wonder: can you add milk to cold brew? The answer is yes—and with the right proportions, the flavors blend surprisingly well.

Cold brew paired with milk isn’t just possible—it can actually enhance each other’s flavors. The coffee, extracted at low temperatures over a long period, has a rounder taste, and adding fresh milk not only softens any potential off-flavors but also adds a silky smoothness and sweetness, enriching the overall drinking experience. However, to achieve the perfect balance between coffee and milk, the key lies in precisely adjusting the ratio among coffee grounds, water, and milk.

Let’s start with bean selection. While almost all coffee beans can be used for cold brew, if you want a bright and sweet flavor profile, it’s recommended to choose light-roasted beans. For example, beans with prominent floral and fruity notes are ideal for those who prefer a refreshing taste. If you prefer lower acidity, dark-roasted beans with nutty or caramel tones are also a great option. No matter which you choose, remember that the low-temperature extraction will result in a gentler flavor, so the quality and characteristics of the beans will have a more direct impact on the final cup.

Regarding grind size, since cold brew is done in a low-temperature environment, the extraction speed is much slower than with hot brewing, so you don’t need an ultra-fine grind like for pour over. Generally, it’s recommended to use a grind slightly finer than pour over—about 75% to 80% through a Chinese No. 20 standard sieve, resembling the texture of fine sugar. If using an electric grinder like the EK43s, set it to a 9.5 to 10 grind setting; for a hand grinder like the C40, aim for around 22 to 26 clicks. This grind size helps release flavors steadily without over-extracting bitterness.

Next is the coffee-to-water ratio. The most common ratio for cold brew is 1:10, meaning 100 grams of coffee grounds to 1000 milliliters of water. This ratio ensures the coffee has enough strength without being overly intense. If you don’t plan to add milk and want to enjoy pure black coffee, it’s suggested to adjust the ratio to 1:12 to 1:13, resulting in a smoother taste and more open aroma. However, if you plan to add fresh milk later, it’s better to maintain a higher concentration of 1:10 to 1:11 to avoid diluted flavors.

As for steeping time, it’s generally recommended to refrigerate the mixture of coffee grounds and water for at least 8 hours, with the optimal time being within 12 hours. Too short a time may lead to under-extraction, while too long can result in over-extracted flavors. Sealing the container with plastic wrap or a dedicated lid helps preserve the flavor and prevents it from absorbing refrigerator odors. After extraction, filter out the coffee grounds using paper or cloth filters to obtain a clear cold brew liquid.

So, how much milk is the right amount to add to cold brew? Based on actual tests, when equal amounts of cold brew were mixed with ice milk at ratios of 1:1, 1:0.8, and 1:0.6 (for example, 100 grams of coffee liquid to 100 grams, 80 grams, and 60 grams of milk), the 1:1 ratio often made the milk flavor too dominant, masking the coffee’s original taste. Meanwhile, the 1:0.8 and 1:0.6 combinations offered a more balanced taste. Especially for beans with pronounced fermented fruity notes, such as certain Panamanian Geisha, the 1:0.8 ratio allows fruit and milk flavors to coexist harmoniously. For beans with a juice-like or berry-toned profile, pairing with milk at a 1:0.6 ratio highlights the coffee’s refreshing qualities even more.

If you don’t have a grinder at home, don’t worry—using drip coffee bags can also let you easily make cold brew. Simply pour the coffee grounds from the drip bag into a lidded container and follow the same coffee-to-water ratio and steps mentioned above for extraction. The only thing to note is that since drip bags use non-woven fabric filters, the filtering process may take slightly longer than with a dedicated cold brew maker. Be patient and wait until it’s fully filtered. This method is especially suitable for busy professionals or coffee lovers who don’t want to buy extra equipment.

In summary, adding milk to cold brew is a simple yet versatile way to enjoy coffee. By mastering the choice of beans, grind size, coffee-to-water ratio, and milk proportion, you can easily make iced milk coffee at home that rivals café quality. Whether you prefer bright floral and fruity notes or richer nutty and chocolatey profiles, by fine-tuning the recipe, you can find your ideal summer iced coffee.

The above content is compiled by CoffeeHunters, a coffee news website.