Why Coffee Bags from Packaging Machines Lose Freshness or Swell After Sealing
After twelve years supporting coffee roasters and co-packing lines, a recurring issue is that bags leave the coffee packaging machine with residual oxygen higher than intended or later develop excess internal pressure. Both problems shorten the period during which aroma and flavor remain acceptable. The combination of incomplete nitrogen displacement at sealing and the behavior of the one-way degassing valve determines whether the package protects the coffee or allows oxidation and mechanical stress.