At True California, we're always looking for ways to maintain quality, freshness, and flavor. It got us to thinking about those gas valves on coffee bean packaging. What do those really do and would those help our walnuts, almonds, or pistachios?
Turns out that those valves are one-way valves designed to release carbon dioxide (CO2) from the packaging while preventing oxygen from entering. Processed and roasted coffee beans release a lot of CO2. The valves help preserve the coffee's freshness by allowing the CO2 gas to escape and by preventing the bag from bursting.
Nuts also release CO2 so could these valves help us preserve freshness for longer? Most information we've found so far say no. Pistachios have been stored in packaging with valves but it's not common and not seen as a The major factors that cause almonds, walnuts, and pistachios to lose their freshness are still oxygen, light and heat, and moisture. That's why we always suggest storing your nuts in a cool and dry location away from direct sunlight.
And if you really had to, you can store almonds, walnuts, and pistachios in your fridge or freezer. Storing them in these lower temperatures can keep them more or less fresh for well over a year. We're not huge fans of this to be honest but some argue it's much better than leaving nuts in hot or humid areas, even if the bag is away from direct sunlight. Just be sure to avoid letting condensation or moisture occur from the rapid change in temperature.
And as for the valves, we're going to keep testing on our own. We test all types of packaging that might preserve our food in safer and more sustainable manner. Lately, we've been conducting more tests with biodegradable and compost-friendly packaging. Some with valves and some without. Each test takes over a year but we hope to share more news soon!
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