Shake it Real Good

The debate about whether shaking your coffee grounds before making espresso can improve extraction has a passionate audience. Initially, Lance Hedrick’s experiments seemed to suggest that a good shake could dramatically boost extraction and reduce shot times. Naturally, this piqued interest and raised a slew of questions.

Lance Hedrick’s experiments showed that shaking coffee grounds before espresso extraction could increase extraction efficiency while reducing shot time. This inspired further tests to explore the mechanics behind this boost, such as the elimination of static or a process called densification. However, when Barista Hustle’s team ran their own tests, the results didn’t match Lance’s findings. In fact, they found that shaking had quite the opposite effect, making extraction times longer and causing grounds to clump together.

Different equipment and settings were tested, including asking Origo Coffee in Bucharest to help. Miruna Tudose, the manager at Origo Coffee, tested various methods: using the Weber Workshops Blind Shaker, a polypropylene cup, the Autocomb, and no shaking as a control. Miruna noted that while the Blind Shaker boosted extraction by over a percentage point, it also made the shots run slower by 3-5 seconds compared to other methods. In another twist, testing with the Autocomb increased extraction and maintained consistency in shot times and percentage — a smaller yet notable increase.

Interestingly, the Blind Shaker didn’t reduce static as expected. Instead, shaking seemed to increase the visible fines in the coffee grounds. Coffee scientist Mark Al-Shemmeri suggested that the manner of shaking could cause fines to separate rather than aggregate, thus increasing their visibility. This demixing effect could be why Barista Hustle’s results differed from Lance’s.

On the flavor front, Miruna and her team noticed distinct differences. Shaking the grounds with the Blind Shaker resulted in a powdery texture and lack of flavor clarity, whereas the Autocomb yielded a brighter, fruitier profile. Despite initial hesitations, the baristas at Origo Coffee found the Autocomb easier to use over time, even during busy periods.

The varying results from different tests suggest that the impact of shaking coffee grounds might depend heavily on the specific combination of coffee, equipment, and techniques used. For example, the type of grinder could play a significant role in how densification and static affect extraction. One thing is consistent: shaking seems to boost extraction, but its effects on shot time and flavor are unpredictable.

Lloyd Meadows from Tortoise Espresso reported that combining shaking with the Autocomb in his routine significantly increased extraction without affecting shot time. This highlights the variability in results and underscores the importance of personal experimentation to find what works best for an individual setup.

While shaking coffee grounds before extraction appears to boost extraction efficiency, the effects on shot times and flavor can vary. Differences in equipment, coffee type, and technique significantly influence the results. For now, the best advice is to try shaking the grounds for yourself and see how it affects your espresso’s quality.