There is no doubt that grinding coffee beans at home is the best way to drink fresh coffee, but this process is quite tedious. The friction created by crushing the beans creates static electricity that causes the coffee to harden and stick to the grinder. But a team of chemists and volcanologists are here to solve this caffeine-induced nightmare, joining forces to investigate how humidity affects this build-up of static electricity. Masu. They found that adding a drop of water to the beans before grinding eliminated static electricity and produced a better-tasting espresso. Their discovery is The study was published in the journal Dec. 6 Case.
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coffee lovers $343.2 billion US coffee industry It has long been known that grinding coffee generates static electricity, but how different characteristics such as origin and roasting affect static electricity has been even more of a mystery.Some baristas are already using it loss droplet technique Use a wet teaspoon or water on the beans before grinding them.
of new research shows how the moisture in espresso beans affects static electricity buildup and how static electricity can be changed. The research team found that when coffee beans have more internal moisture, they generate less static electricity. This eliminates some waste, gives consumers better value for money, and produces a more consistent and intensely flavored espresso.
“Moisture, whether it’s residual moisture inside the roasted coffee or external moisture added during grinding, determines the amount of charge that forms during grinding,” said study co-author and University of Oregon professor says computational materials chemist Christopher Hendon. stated in a statement. “Water not only reduces static electricity and reduces mess during grinding, but it can also have a significant impact on the strength of the beverage and potentially its ability to obtain a higher concentration of desirable flavor.”
To study what factors are behind power generation, Hendon collaborated with a team of volcanologists. During volcanic eruptions, scientists study similar electrification processes.
“During an eruption, magma breaks up into lots of tiny particles that come out of the volcano in this big plume. And during that whole process, those particles rub against each other and become electrically charged to the point where they create lightning. ,” the research team said. -Joshua Mendez Harper, author and volcanologist at Portland State University said in a statement. “Simplistically speaking, it’s like grinding coffee, grinding the beans into a fine powder.”
We grind both commercially available espresso beans and home-roasted espresso beans. Beans vary based on factors such as country of origin, roast color, processing method (natural, washed, or decaffeinated), and moisture content. They measured the amount of static electricity generated during grinding and compared the effect of grinding roughness on the amount of electricity generated.
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There was no correlation between static electricity and where it was produced in the country or how it was disposed of.However, the team discovered Relationship between electrostatic charge, particle size, roasted color, and moisture content.
If coffee has a high internal moisture content and is ground at a coarser setting, less power will be produced. The shallower the roast, the less charge is produced and the more likely the charge is to be positive.
Dark roasts tend to be drier, and the dark roasts studied were negatively charged and produced more charge overall. The researchers also found that dark-roasted coffee produced much finer particles than light-roasted coffee when ground using the same settings.
The team then tested whether grinding the beans with water changed the way the espresso was made. Even with the same beans, beans ground with water had a longer extraction time and were able to produce a stronger extraction. Using water in the grinder also produced espresso shots that tasted similar from shot to shot.
Although the research team only tested espresso, they believe these benefits apply to many other brewing methods as well.
“The main material benefit of adding water during grinding is that there is less agglomeration and the bed can be packed more densely,” says Hendon. “While espresso is the biggest culprit for this problem, we also see benefits in brewing formats where you pour water over the coffee, or even smaller osmosis systems like stovetops. It’s like a French press, where you soak it in water.”
In future research, the team plans to further explore their quest to prepare the world’s best coffee. This study has implications beyond caffeine intake and may provide insight into how caffeine is consumed. particulate matter It is electrified.
“This is kind of the beginning of a joke, where a volcanologist and a coffee expert walk into a bar and come out with a paper, but I think there are many more opportunities for this kind of collaboration. “We know how coffee breaks down, how it flows as particles, and how it interacts with water,” said Mendez-Harper. said. “These studies could help solve parallel problems in geophysics, such as landslides, volcanic eruptions, and how water infiltrates the soil.”
