WEBER WORKSHOPS Bean Cellar: Experimenting with Freezing Coffee

Freezing coffee isn’t as taboo in Specialty Coffee as it once was. We must mention off the bat: please don’t just throw an open bag of coffee in the freezer. The grandma method (sorry, we love you, maw-maw) is the wrong way to go for several reasons. The key to success is storing your coffee properly, which requires the correct vessel. In comes the Bean Cellar by Weber Workshops, made with a food-grade polymer intended for use in café and home settings. 

Hypothesis: Freezing Will Improve Your Espresso 

Sealing your beans properly—in a small airtight capsule—will significantly extend their shelf life without any adverse effects. We like having multiple tubes of beans ready to go so we don’t have to constantly expose one bag of beans to the air each time we need a dose. 

We currently stock the glass Bean Cellar, which is not intended to be stored in the freezer (for breakage reasons) but is meant to be displayed on a counter next to your beautiful espresso setup. You still get the benefits of proper bean storage by preventing oxygen exposure, thus accelerating the aging process of your precious beans. The cellar’s cap design allows the natural CO₂ from freshly roasted beans to escape, gently pushing out oxygen and preserving each dose's rich, complex flavors. Freezing the beans will stop oxygen from escaping the Bean Cellar, preserving your coffee in time. The food-safe polymer tubes prove to be durable as well. This storage method will eliminate excess water, defrosting, and odor accumulation from consistent re-exposure to oxygen, thus helping you maintain optimal flavor every time you reach for a fresh vial of coffee to grind. All of this generally makes sense to us, but if we want to start carrying the polymer version of the tubes, we have to put them to the test. 

Test Methodology & Results: Room Temperaure vs. Thawed vs. Frozen

We use Kickstep Blend by the Great North as our test coffee and use willing test subjects from Clive HQ to blind-taste some of the results. A few variables to consider during this test:

• What impact will freezing have on the moisture distribution of the beans?
• What impact will brief air exposure have on the beans? 

Even if very briefly, we found that a layer of moisture collected on the surface of the bean, and any user of RDT (Ross Droplet Technique) will know that adding a little bit of moisture can positively affect extraction. 

We pulled 24 shots in alternating fashion and tasted them: 6 frozen, 6 frozen then thawed, and 12 with unfrozen room temperature beans. 

• Doses ground, while still frozen, had a slower flow rate, dropping from a consistent 35g yield to 30g. This indicates what many other experiments have found: Frozen beans produce a consistent particle size that trends finer. 
• The resulting resistance from the puck gives you a slower flow rate during brewing. 
• Additionally, this produces a higher extraction yield, meaning you get more tasty particles out of the same coffee puck in less time. 

Grinding the beans while still frozen had a much larger impact on flavor than the room temperature and thawed beans. The frozen beans were consistently crisp, with a bright front-end, almost effervescent, which is quite unusual for a darker espresso blend like Kickstep. 

Have you tried freezing your beans at home? Do you work in a café that freezes their beans for service? If you try our experiment at home, please sound off in the comments, we would love to hear your results. Happy brewing!