The Role of Brew Ratio in Making Great Coffee
You can describe coffee brewing by the scientific definition: extracting soluble materials (like caffeine, carbohydrates, lipids, acids, and sugars) from ground, roasted coffee beans. Or you can define it as simply as mixing ground beans from your coffee roaster with hot water. Whether we get a satisfyingly balanced, complex and aromatic coffee or a sour, bitter concoction depends on the quality of the beans, the water quality and how the coffee is brewed. Aside from water temperature, brewing time, grind size, and the device, brewing coffee has a lot to do with the brew ratio. What is the brew ratio, and why does it play a big part in determining how good our coffee is?
What is Brew Ratio?
The brew ratio is defined as the ratio of ground coffee beans to water. Baristas use the brew ratio as the base of their recipe, and as a guide when they want to scale up or scale down the amount of coffee they brew. Some people talk about 1:15 (15 grams of water for every gram of coffee) as a Golden Ratio, an ideal number to make that perfect cup of coffee. However, things aren’t always that simple, especially when it comes to brewing coffee. There isn’t really a fixed set ratio for every barista, every type of coffee bean, every brew method.
Different Brew Ratios For Different Brew Methods
Below are some general guidelines about the brew ratios used on several commonly used brew methods:
Brewing by immersion means keeping the coffee grounds fully submerged in hot water over time. As the water and the coffee sit together for a certain time, there is a chance of saturation which can be solved by agitating the mixture or using a higher brew ratio to ensure more flavor.
Example: french press, aero press, siphon and during cupping session
Recommended brew ratio: between 1:12 to 1:15
In this method of brewing, hot water is slowly flowing through a bed of ground coffee and a filter. It is a more efficient way to brew because there is a constant supply of hot water running through the coffee. This helps extract all of the TDS (Total Dissolved Solids) without the risk of over-saturation.
Example: V60 drip method, and all other drip/filter methods
Recommended brew ratio: between 1:15 to 1:17
This is a brewing method where the ground coffee beans are extracted under pressure, using a specialized equipment, making it quicker and more efficient. Typically an espresso has a much smaller serving size, and also much more concentrated.
Recommended brew ratio: between 1:1 t0 1:4
With a cold brew method, the coffee ground is steeped in room-temperature or cold water for an extended period of time. Cold brewing is a much less volatile process, but it does take more time which means a much greater chance of saturation. As a result, more coffee is needed to produce an acceptable flavor.
Recommended brew ratio: between 1:5 t0 1:8
These guidelines are good starting points for developing your own brew recipe. However, to really know what works best, you’ll have to do your own trial and error. Try different brew ratios with different coffees and discover the results.
The Role of Brew Ratio In Making Great Coffee
Brew ratio is important because it affects how much of the desired flavors are extracted out of the coffee beans without getting too much of the undesired ones. Under-extracted coffee is often sour without much sweetness, while over-extracted coffee pulls more acidic, bitter flavors out.
With clever measurement and calculation, you can consistently improve the quality of your brew. And with a little experimentation, you might find your own Golden Ratio for your favorite coffee beans.
Measuring both your coffee and your water carefully is crucial if you want to use these ratios correctly. Doing it consistently will also help you to easily repeat a recipe. Weight, not volume, is the best way to quantify your brew recipes. A digital gram scale is very likely your most reliable tool when brewing coffee. It is recommended to purchase one that is waterproof and has a protective covering from heat.