Freshly roasted coffee beans release carbon dioxide (CO2) for days after roasting. If that gas has nowhere to go, a sealed bag can puff up or even burst. A one-way degassing valve solves this problem.
How does a one-way valve work?
The valve is a small plastic fitment welded to the inside of the bag. It lets built-up CO2 escape from the bag, but does not let outside air flow back in. That means the bag stays flat and the coffee is protected from oxygen, which causes staling.
Benefits for roasters
- Pack immediately after roasting — no need to wait days for beans to degas.
- Longer freshness — oxygen and moisture stay out.
- Better presentation — bags do not bloat on the shelf or in transit.
- Customer experience — shoppers can gently squeeze the bag to smell the aroma through the valve.
Do ground coffee bags need a valve?
Ground coffee releases most of its gas faster than whole beans, but many roasters still use valves for freshly ground coffee packed soon after roasting. For whole beans, a valve is strongly recommended.
Choosing the rest of your coffee bag
- Structure: a foil or high-barrier inner layer protects against oxygen and light; kraft paper outers give a natural look.
- Style: stand-up pouch, flat-bottom bag or side-gusset bag.
- Closure: resealable zipper, pocket zipper or tin-tie.
- Size: common sizes are 250g, 500g and 1kg, but any custom size is possible.
Need help choosing? Send us your product details and our team will recommend the right bag structure and give you a quote within 24 hours.