There’s a chance that any of the 250g Sample Coffee bean bags you buy looks like a party balloon.
This ‘puff’ is caused by the absence of a degassing one-way valve, an element that allows post-roast gases to escape out of the bag without allowing air and moisture in.
We removed the valves from our 250g bean bag design when we switched from soft plastic to ABA home compostable certified material in 2023. The reason? To reduce waste, because those extra squares are made of a material classified as general waste.
After years of roasting and packing bags, our intuition told us we might get away without valves in small coffee bean bags. Small bean quantity = small volume of post-roast gas = manageable pressure.
Tests before committing to the new design showed promising results: the bags puffed up at different degrees depending on the coffee and conditions, but they never broke, and the coffee tasted just as good. And, after +2 years of use in our cafes and online trade, we’ve never seen or heard of a bag compromised by the gas pressure; just the odd puzzled customer asking if this look was a normal thing.
So, our puffy bags are fine and normal. They’re saving an extra piece of unnecessary waste going to landfill while carrying the beans safely to your home.
On the left, a valveless, puffy 250g bag; in the centre and right, a 500g and a 1kg bag
Curious or new to degassing, packaging and our design philosophy? Check the questions below.
Why do roasted coffee beans release gas?
Green coffee beans release numerous aroma compounds and carbon dioxide gas (CO2) as they reach high temperatures inside the roaster.
Some of this CO2 remains trapped inside the beans’ body and is gradually released over the following hours/days/weeks (this is generally known as the degassing period).
Do all coffee beans degas in the same way?
No. It depends on many factors, like the bean size and body structure, type of roasting, environmental conditions…
For example, as a general rule, our espresso blends release more gas than our single origins as they’re roasted darker (so these bags generally puff up more).
What do coffee bag valves do?
Coffee bag valves are one-way valves, which means they allow gases to escape out of the bag but don’t let other gases from our atmosphere (air, humidity, oxygen) inside.
Why did you remove the valve only on your 250g bean bags?
After some research and testing, we confirmed that the bags and coffee remained safe and delicious without the valve, saving an extra piece of general waste from going to landfill.
This wasn’t the case for bags above the 250g format; more beans release more gas, hence building higher pressures. We needed to keep the valve to ensure their structural integrity.
Do beans that age in a valveless bag taste good?
According to our tests, with our coffee, yes. Oxygen and humidity don’t come inside the sealed bag, so the natural aging process occurs in the same way as in bags that feature a valve.
Is degassing related to flavour and acidity development?
Yes, that’s why if you brew your coffee too soon post-roast date, it may taste a bit weird, metallic, not good—there’s still too much CO2 in the beans.
Learn more in our recommended brewing window.
How do you feel about the puffy look?
We’re aware it’s not the most Instagrammable look, but it aligns with our philosophy: delicious, high-quality coffee, maximum social impact, and a minimum environmental footprint.
When it comes to packaging, we seek the option that best balances coffee quality and environmental preservation (something that, no joke, changes year on year as technology, culture and policies evolve). This involves not only material choices (such as certified ABA home compostable) but also what’s called source-reduction exercises (essentially, what we’ve done with valve removal—finding ways to reduce waste).
In this case, the real beauty, what really matters, is definitely on the inside.