Nitrogen Flush & Freshness
Nitrogen flushing is a commonly used method for extending the shelf life of coffee. Fill the package with inert Nitrogen, displace the oxygen, which is the primary component of staling, and voila, extended freshness!
But many of our roaster clients are asking: When it comes to packaging coffee in pods, do I really need to nitrogen flush? Like a lot of things, the honest answer is - it depends. While our equipment provides nitrogen flush capability, the necessity of using it is really all about the length of time between filling and consuming.
Fresh roasted coffee will out-gas CO2 at approximately 10 Liters gas per kilo of coffee, most of it in the 72 hours after roasting. Relating this to single serve pods means that a 12 gram fresh fill will release nearly 7.4 cubic inches of CO2, nearly triple the volume of a single serve pod. Conventional pods and their paper filters require a waiting period after roasting to prevent bursting from the over pressure of CO2 into a sealed pod.
But, iFillCup® pods are designed to be different. Talk about grace under pressure, the picture above shows a fresh filled iFillCup® pod weighted down and under water as an air bubble passes thru the perimeter of its one way flow degassing seal. Allowing over pressure to escape means the CO2 will force atmospheric oxygen out of the pod, and thus naturally reduce oxygen levels. Ideally this lowers oxidation and staling sufficiently to extend shelf life freshness to as much as 4 months.
Time is the Answer
So back to the question, do I really need to nitrogen flush? We highly recommended it if your roaster to consumer timeline exceeds 4 months. If your roaster to brewed cup is less than 4 months then its not so crucial but of course the choice is yours.
In the world of coffee freshness is king: fresh grinding and filling right after roasting is key, and nitrogen flushing, while not a cure all, will help keep the king on his throne a little longer.