Milk-Brewed Coffee: A Cold Brew Method Using Milk Instead of Water

Milk-brewed coffee replaces the water in cold brew with fresh milk. Coffee grounds soak in milk at low temperature for several hours, then get filtered. The cold extraction limits bitterness and off-flavors. Milk adds a smooth, silky texture similar to chocolate milk while carrying the bean's aroma. For beans, choose a medium roast or darker with notes like chocolate, hazelnut, caramel, or cream. Light roasts can taste thin because milk suppresses their brighter flavors.

Grind slightly finer than for regular cold brew. Coffee-to-milk ratios from 1:8 to 1:12 work well; lower ratios give a richer drink, higher ratios a lighter one. You can brew by direct immersion or use a filter bag for easier cleanup. After brewing, store the finished coffee in the refrigerator and drink within a day or two. This method offers a different way to enjoy iced milk coffee at home.

Replace the water in cold brew with fresh milk, soak the coffee grounds at low temperature for an extended period, and after filtering you get a silky, rich milk-brewed coffee. This method has recently drawn attention in the coffee community and is being called a new choice for cold brew iced milk coffee lovers. This article will start from the principles of milk brewing, explain why low-temperature extraction can reduce bitterness and off-flavors, and how milk gives coffee a smooth texture like chocolate milk. Then it will break down the practical points one by one: what roast level and flavor type to choose for coffee beans, the actual performance differences between fresh milk and oat milk, whether the grind should be coarser or finer than regular cold brew, what mouthfeel the 1:8 to 1:12 coffee-to-milk ratios each present, the trade-offs between direct immersion and bag-separated extraction in terms of time and convenience, and whether it can be stored overnight after making. The article also retains Front Street Coffee's demonstration and specific parameters using two beans: Brazil Queen's Estate and Colombia Flower Moon Night.

While browsing online recently, Front Street Coffee noticed a coffee-making method called "milk brew," and some even call it good news for cold brew iced milk coffee lovers. That being the case, today let's try making it ourselves.

What exactly is milk brew coffee?

As the name suggests, milk brew is simply replacing the water in cold brew with fresh milk, letting the coffee grounds soak in a low-temperature environment for several hours, dissolving out the flavor compounds, and then filtering to get a cup of milk coffee. Because the temperature stays low throughout, bitterness and off-flavors are not easily released. In addition, the originally flavorless water is replaced with rich, smooth milk, which interweaves with the aromas extracted from the coffee grounds. The final product has a silky touch similar to chocolate milk while retaining the aroma profile of the selected coffee beans.

How should coffee beans and milk be chosen?

The biggest difference between milk brew and regular cold brew is that milk plays a very heavy role in it. If you choose a bright, light-roast bean, the coffee's aroma will mostly be suppressed by the milk flavor, and it will taste rather thin—at best like a glass of milk with a bit of fruit acidity.

So when choosing beans, Front Street Coffee recommends using coffee beans with a medium roast level or above and flavor descriptions such as chocolate, hazelnut, caramel, or cream, or beans with fermented notes or winey aromas for making milk cold brew. For this demonstration, Front Street Coffee used medium-dark roasted Brazil Queen's Estate and anaerobic natural medium-roasted Colombia Flower Moon Night. The former tastes like hazelnut cream dark chocolate, while the latter is closer to nutty cranberry dried-fruit milk chocolate.

For making cold brew milk coffee, Front Street Coffee believes fresh milk is more suitable. Fresh milk's high lactose and milk fat content can elevate the coffee's smoothness and body to another level; here, Bright Fresh Pasture is used. Front Street Coffee also tried making milk brew with OATLY oat milk, and the mouthfeel came across as very jarring.

How fine should the coffee grounds be ground?

The first time Front Street Coffee tried it, the cold brew grind size was used directly (80–85% passing through a No. 20 sieve). Although the filtered milk coffee was fragrant, the bitterness was rather heavy, leaving an uncomfortable residue in the mouth. So the grind was adjusted coarser to near the standard for hot pour-over (75–80% passing through a No. 20 sieve), and the bitterness decreased accordingly. For better aroma in the milk coffee, the coffee beans are best ground and brewed fresh so that aromatic compounds are preserved to the greatest extent.

What ratio of coffee beans to milk is appropriate?

To find the optimal ratio, Front Street Coffee used Bird of Paradise for the demonstration, keeping the same grind size (EK43S setting 10.5) and extracting at three standards: 1:8, 1:10, and 1:12. Each batch used 25 grams of coffee grounds, with 200 grams, 250 grams, and 300 grams of iced fresh milk poured in respectively.

In comparison, 1:10–1:12 has a moderate strength, with coffee and milk matching just right; it tastes like an iced latte without ice. 1:8 has the darkest coffee color, with both coffee and milk flavors more substantial; drunk straight, it is close to a latte made with purified milk, and is suitable for drinking after adding ice cubes.

Direct immersion or bag-separated extraction? How long to soak?

The soaking method depends on what tools you have on hand—put simply, do whatever is convenient. If you have both a cold brew pot and tea bags, you can put the coffee grounds in the bag and throw it away directly after soaking, which saves quite a bit of effort. But because the coffee grounds are separated, the contact between grounds and milk is not sufficient enough, and it needs to soak for more than 10 hours to develop flavor; during that time, you also need to turn the bag occasionally to improve extraction.

If, like Front Street Coffee, you have a pot, a dripper, and filter paper but no filter bag, then use the most direct method: soak the coffee grounds and fresh milk directly together, then filter out the coffee grounds with filter paper after soaking. Direct immersion allows soluble substances to enter the milk more fully, and extraction is complete in just 5–6 hours. The biggest drawback is that filtering takes a bit of waiting time.

Should the finished coffee be drunk directly or put in the refrigerator?

Front Street Coffee first tasted the freshly filtered Queen's Estate cold brew milk coffee. It had a rich milk-tea color, smelled of hazelnut and roasted peanut, and tasted fragrant, thick, and silky on the palate. After leaving it overnight to ferment and then drinking it, the mouthfeel difference was not great, but the aroma was noticeably weaker. Considering that milk spoils extremely easily, Front Street Coffee suggests drinking the finished milk brew coffee the same day if possible to avoid intestinal discomfort.

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