Atmos Vacuum Canister). Here’s a handy guide on coffee freshness that explains why vacuum canisters are so effective at keeping your coffee fresher, longer.

Why is oxygen so bad for coffee beans?
Oxygen is bad for coffee, snacks, or pretty much any perishable item because it makes things stale through a process called oxidation. To set the stage, we define “staleness” as the loss of desirable flavors and aroma, and/or the creation of undesirable flavors and aroma. When oxygen comes in contact with a molecule, it removes an electron from the molecule. This is called oxidation. The molecule that loses an electron becomes unstable and reactive, which then results in the loss of flavor or creation of an undesirable flavor.

For coffee beans, oxygen negatively affects VOCs (volatile organic compounds). VOCs are chemical byproducts of roasting that evaporate quickly. They are generally considered good because they contribute to aroma.³ When oxygen comes in contact with VOCs, they become unstable and result in coffee losing its aroma.

Oxygen also affects lipids, which are the coffee oils in the bean. Oxidation turns lipids into peroxide which contributes to rancid taste notes.⁷

Additional questions?
We hope this answers your questions on vacuums, coffee freshness, and Atmos Vacuum Canister! As always, we will continue posting our research as we receive questions from customers and the coffee curious. If you have additional questions or comments reach out to hello@spokenpsalms.com, so we can continue serving up the latest and greatest coffee information!

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REFERENCES

1.) Cengel, Y. A., & Boles, M. A. (2012). Thermodynamics An Engineering Approach. McGraw-Hill Science Engineering.

2.) Illy, A., & Viani, R. (2005). Espresso coffee: The science of quality. Amsterdam: Elsevier Academic Press.

3.) Rao, S. (2014). The coffee roasters companion. Canada: Scott Rao.

4.) Raper, A. Is Your Coffee Too Fresh? Retrieved from . 5.) Sage, E. (2017). What is the Shelf Life of Roasted Coffee? A Literature Review on Coffee Staling. Retrieved from .

6.) Schenker, S. (2000). Investigations on the hot air roasting of coffee beans. Zürich: ETH Zürich.

7.) Smith JP, Daifas DP, El-Khoury W, Koukoutsis J & El-Khoury A. (2004). Shelf Life and Safety Concerns of Bakery Products: A Review. Critical Reviews in Food Science and Nutrition 44(1):19-55.