Why do coffee beans need to be left to rest for 7 days before they can be ground?

Why do coffee beans need to rest for 7 days before they can be ground?

Coffee is one of the most popular beverages in the world, and coffee beans are the key to making delicious coffee. However, you may be surprised to learn that after purchasing fresh coffee beans, professionals usually recommend letting them sit for 7 days before grinding. There is some science and practical experience behind this practice.

1. Coffee Growing and Harvesting

To understand why it takes 7 days to grind coffee beans, we first need to understand the coffee growth and harvesting process. When the ripe coffee fruit is picked, it contains two seeds, the so-called "coffee beans". These freshly picked beans usually have a higher moisture content.

2. The period of dramatic change

During the dormancy period, freshly picked, untreated or wet curry seeds undergo a series of chemical and biological changes. This process is a critical stage in the growth and maturity of coffee beans.

During this period of rapid change, the coffee beans release carbon dioxide and continue to absorb oxygen. This leads to complex reactions within the beans, including enzyme activity and protein breakdown. These reactions are crucial to the flavor and aroma that are ultimately desired in high-quality coffee.

3. Reduce acidity

Freshly picked coffee beans typically have higher acidity levels, and resting for seven days can help reduce this acidity. After the upheaval period is over, some of these compounds will gradually break down or transform into other forms over time.

For example, during the standing process, organic acids such as malic acid and citric acid will gradually degrade or convert into other substances. In this way, the ground coffee will no longer have such a sharp or irritating taste.

4. Increase sweetness

In addition to reducing acidity, resting can also increase the sweetness of coffee. After the rapid transformation period, the sugar inside the beans will gradually convert into soluble sugars and combine with other compounds to form a more complex flavor.

This transformation process takes time to occur, so leaving it to rest for 7 days ensures that the beans develop their best flavor characteristics. The resulting coffee will have a more intense and balanced taste.

5. Stabilize moisture content

Freshly picked coffee beans usually have a high moisture content, which is not good for grinding and brewing. High moisture content will result in more fine particles when grinding and may affect the extraction effect during brewing.

By resting for 7 days, the moisture inside the coffee beans will gradually stabilize and reach an ideal state. This will allow for a more uniform and stable particle size and better control of the extraction effect during grinding and brewing.

Summarize

The 7-day rest period allows the coffee beans to fully develop their best flavor characteristics. During this process, chemical and biological changes within the beans will gradually reduce acidity, increase sweetness, and stabilize moisture content.

Therefore, if you want to make a coffee with better taste, more depth and complexity, it would be a wise choice to let the freshly picked coffee beans rest for 7 days before grinding.