Regrinding Coffee - A Surprising Result

Summary

In this video, the narrator explores an intriguing experiment suggested by engineer Tommy Ogawa, involving the regrinding of already ground coffee to create a more flavorful espresso. After initially expecting a poor outcome, the narrator discovers that slowly feeding coarsely ground coffee into a grinder results in a finer grind and faster shot, with a sweeter and more balanced taste. This leads to a discussion on grinder resistance and the potential benefits of regrinding, challenging conventional wisdom. The video encourages viewers to replicate the experiment and share their findings, sparking curiosity in the coffee community.

Takeaways

• 😀 A viewer, Tommy Ogawa, suggested experimenting with regrinding coffee to see how it affects espresso shots.
• 😀 The initial experiment involved grinding coffee very coarsely and then grinding it again, which led to a shot that brewed very slowly and tasted bad.
• 😀 The key discovery was that the rate at which coffee is fed into the grinder can significantly alter the grind profile and espresso shot quality.
• 😀 When coffee is fed into the grinder slowly, it produces a finer grind, resulting in a sweeter, more balanced espresso shot.
• 😀 The experiment involved adjusting the grind setting and feeding ground coffee very slowly into the grinder, which resulted in a noticeably better shot.
• 😀 The video presenter highlights that grinder exit resistance plays a role in how the coffee is ground, similar to issues seen with the Mythos 1 grinder.
• 😀 A theory is proposed that the slower the coffee moves through the grinder, the finer it becomes, which can improve the flavor of espresso.
• 😀 The presenter cautions viewers about regrinding coffee at home, as it could potentially damage grinders, particularly with certain models.
• 😀 Despite the risks, the presenter suggests a follow-up experiment: feeding whole coffee beans into the grinder very slowly, which might yield similar results to regrinding.
• 😀 The experiment with whole beans involves patience, as slower grinding results in a finer, more enjoyable espresso shot, with no shortcuts to the process.

Q & A

What experiment did James Hoffman conduct with his coffee grinder?

James Hoffman experimented with regrinding already ground coffee by feeding it back into his grinder at a very coarse setting and doing it slowly to see if it would affect the taste and extraction of his espresso shots.

What was the initial expectation James had before conducting the experiment?

James expected that grinding coffee twice would generate more fines, leading to a slower extraction and potentially choking the shot, but this was not the case when he adjusted the rate at which coffee was fed into the grinder.

Why was the speed of feeding coffee into the grinder important in this experiment?

The speed of feeding coffee into the grinder influenced the grind size. If coffee was fed in slowly, it produced a finer grind, and if fed quickly, it ground coarser, impacting the extraction time and espresso flavor.

What role does the resistance in the grinder play in the outcome of the grind?

The resistance in the grinder affects the time coffee spends in the burr set. More resistance means coffee stays longer in the burrs, resulting in a finer grind. Less resistance speeds up the grinding process, resulting in a coarser grind.

What did James discover when he adjusted his grinder and fed ground coffee in slowly?

When James fed ground coffee into the grinder very slowly, he discovered that it produced a much faster shot with better taste, even though he kept the grind setting the same as before.

What is the theory behind the 'popcorning' phenomenon in grinders?

Popcorning occurs when the hopper is nearly empty, and the remaining beans grind coarser because there's less coffee feeding through the grinder. James speculated that the less congested burr set could produce a better grind profile, even though it seemed undesirable.

What did James think about the shots when he fed coffee into the grinder slowly?

James found that the espresso shots were sweeter, more balanced, and more enjoyable when he fed the coffee into the grinder slowly compared to shots made with freshly ground beans.

What advice did James give viewers regarding regrinding coffee?

James advised viewers to experiment with slowly regrinding coffee, but cautioned them about potential issues with different grinders. He also recommended trying the method with whole beans as well.

What alternative experiment did James suggest for viewers who are hesitant to try regrinding coffee?

James suggested that viewers could try slowly feeding whole beans into their grinders, which would have a similar effect to regrinding ground coffee, and report their findings.

What is the significance of the anti-popcorning disc in James' experiment?

James noted that adding the anti-popcorning disc to his Niche grinder may have helped improve the shot quality by slowing the flow of coffee into the burrs, though he speculated it was more about the slow feeding process than the disc itself.