Introduction:Want to try something different with cold brew? Replace water with milk and use low-temperature, long-duration extraction to create a silky and rich milk-brewed coffee. This article will detail the principles behind milk-brewed coffee, step-by-step instructions, selection of coffee beans and milk, grind size and ratio parameters, and an analysis of the pros and cons of different methods — helping you easily master the brewing secrets of this cozy winter drink.

By replacing the water in cold brew with fresh milk and steeping the coffee grounds at a low temperature for an extended period, followed by filtration, you can enjoy a cup of milk-brewed coffee with a silky-smooth texture. This innovative brewing method has gained popularity among coffee enthusiasts in recent years, especially appealing to those who enjoy a rich taste but want to reduce bitterness. This article will delve into the principles behind milk-brewed coffee, explaining how low-temperature extraction effectively minimizes the release of off-flavors, and how milk contributes a creamy, chocolate-milk-like body to the coffee. We’ll also break down the key practical steps, including selecting the roast level and flavor profile of the coffee beans, comparing the performance of fresh milk versus plant-based milks, fine-tuning the grind size, understanding the impact of coffee-to-milk ratios, comparing the two main extraction methods, and offering storage recommendations.

As the name suggests, milk-brewed coffee uses milk instead of water to extract coffee. This brewing method is similar to traditional cold brew, but replaces plain water with fresh milk, allowing the coffee to slowly release its flavor compounds in a low-temperature environment. After several hours of steeping and filtration, you get a beverage where the aroma of milk and coffee blend perfectly. Since the entire process occurs at a relatively low temperature, it effectively suppresses the release of excessive bitterness and impurities. Coupled with the naturally smooth texture of milk, the final product has a velvety mouthfeel reminiscent of chocolate milk, while also showcasing the unique aromatic characteristics of the selected coffee beans.

When selecting coffee beans, the biggest difference between milk-brewed and regular cold brew lies in how significantly milk affects the flavor. If you choose a light roast with a brighter, more acidic profile, its distinctive characteristics are often overwhelmed by the strong milk flavor, resulting in a weak overall layering — or it may just taste like a fruit-acid-laced milk tea. Therefore, it’s recommended to opt for medium to dark roasts with flavors of chocolate, hazelnut, caramel, or creaminess, or beans with fermented wine-like notes, which can achieve a synergistic effect with milk. In our practical demonstration, we used a medium-dark roasted Brazilian Queen Estate bean, showcasing flavors like hazelnut cream and dark chocolate, as well as an anaerobically sun-dried medium roast Colombian Huayueye, which presented a milk chocolate taste with notes of nuts and cranberries.

As for milk selection, it is recommended to prioritize fresh whole milk, whose rich lactose and milk fat not only enhance the overall body of the drink but also intensify the silky texture. For this demonstration, we used a local fresh milk brand that brought out a smoother, gentler milk aroma. Although we also tried commercially available oat milk, we found its taste to be somewhat disjointed when paired with coffee and milk, so it is not recommended as the first choice.

In terms of grind size, if you directly use the typical grind size for cold brew (about 80–85% passing through a #20 sieve) on your first try, although it can yield a rich body, it may also produce an undesirable bitterness that lingers unpleasantly. Later adjustments to a coarser grind, similar to that for hot pour over (75–80% passing through a #20 sieve), clearly reduced bitterness and resulted in a more balanced cup overall. Additionally, to preserve more aromatic compounds, it is recommended to grind the beans just before brewing to achieve the best flavor expression.

Regarding the coffee-to-milk ratio, we conducted tests using the same grind size (EK43S setting 10.5), with 25 grams of coffee grounds and three different ratios — 1:8, 1:10, and 1:12 — corresponding to 200 grams, 250 grams, and 300 grams of fresh milk, respectively. The results showed that the 1:10 to 1:12 ratios achieved the best balance, with the flavors of coffee and milk complementing each other, resulting in a refreshing and smooth mouthfeel akin to iced latte. The 1:8 ratio, on the other hand, offered a stronger coffee and milk flavor with a darker hue, making it suitable for those who prefer a richer taste; adding ice is suggested to balance the overall flavor.

For extraction methods, there are mainly two: direct steeping and using a tea bag for separation. If you have a cold brew pitcher and a tea bag on hand, you can place the coffee grounds in the bag for steeping and simply remove the bag afterward, which is more convenient. However, due to the smaller contact area between the grounds and the milk, the steeping time needs to be extended to over 10 hours, and occasionally shaking the tea bag can improve extraction efficiency. If no tea bag is available, you can also place the coffee grounds and fresh milk directly into the cold brew container for steeping without separation. This allows for more thorough extraction and can be completed in about 5–6 hours, but filtering may require a bit of patience to allow the grounds to settle.

Finally, regarding storage, freshly filtered milk-brewed coffee has a rich color resembling that of milk tea, with aromas of hazelnuts and roasted peanuts wafting from the cup. It tastes rich, thick, silky, and smooth. Even if left overnight, the flavor changes aren’t very noticeable, but the aroma will diminish to some extent. Since milk is prone to spoilage, for food safety reasons, it is best to consume milk-brewed coffee the same day to avoid the risk of stomach discomfort.

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