Why is some coffee bitter despite being light, and some coffee bland despite being strong? A very critical factor is the coffee powder to water ratio during brewing. The same coffee beans, brewed with different coffee powder to water ratios, can produce two cups of coffee with completely different styles. The right coffee powder to water ratio is one of the key factors to make a cup of coffee taste good.
The coffee powder to water ratio (Coffee to Water Ratio) required for coffee extraction is usually expressed as 1:X, where X is the weight of water required for every gram of coffee powder. For example, if the coffee powder to water ratio is 1:20, 15 grams of coffee powder requires 300 grams of water.
Imagine that, under the same other conditions, using 20 grams of water and 200 grams of water to brew two portions of 10 grams of coffee powder respectively, the results are obviously very different. When brewing with 20 grams of water, the concentration of coffee is very high, but because the amount of water is too little, the soluble substances in the coffee cannot be fully extracted. Only the more soluble part of the surface of the coffee powder can be extracted. The resulting coffee has high acidity, a single taste, and insufficient extraction. When brewing with 200 grams of water, the extraction is very sufficient, and even some bitter substances that are difficult to extract and we don’t want are extracted, resulting in over-extraction, but the concentration is very low. Such coffee is both thin and bitter.
So, what is the right coffee to water ratio? In the 1950s, E.E.Lockhart, a professor of chemistry at the Massachusetts Institute of Technology, led a series of studies and obtained the preferences of ordinary Americans for coffee flavors at the time through a large number of questionnaires. In the following decades, this preference has basically not changed and has been proven to be applicable in other countries. This is the "Golden Cup" standard. To achieve the Gold Cup standard, the coffee to water ratio needs to be 1:15~1:20. The coffee to water ratio currently recommended by the Specialty Coffee Association SCA is also within this range. The most commonly recommended coffee powder to water ratio is 1:15~1∶16, that is, 15 grams of coffee powder corresponds to 225~240 grams of water.
In addition to the drip extraction method represented by hand brewing, other extraction methods require a corresponding coffee powder to water ratio. For example, since the French press uses immersion for extraction, the area of coffee powder in contact with water is large, so the amount of water can be reduced, and the coffee powder to water ratio is 1:12~1:15; cold brew coffee requires longer time and more coffee powder due to the low water temperature, so a coffee powder to water ratio of 1:5~1:8 is more suitable; and espresso uses high temperature and high pressure, so the extraction efficiency is extremely high, and the coffee powder to water ratio is roughly 1:2~1:3.
When making coffee, it is crucial to choose the right coffee powder to water ratio. It not only affects the taste, flavor and concentration of coffee, but is also directly related to the overall quality of coffee. In addition, we also need to remember that the coffee powder to water ratio is not the only factor that determines the quality of extraction. Water temperature, extraction time, coffee grinding degree, extraction method, etc. will also affect extraction. Adjustment of one variable during extraction may require corresponding adjustments to other variables. Therefore, when making coffee, it is recommended to adjust the powder-water ratio according to your taste preferences, coffee types and roasting degree, and find the most suitable ratio for you through repeated tasting and concentration testing. At the same time, you can also refer to the powder-water ratio range of the common coffee making methods mentioned above as a reference.
