Coffee Packing Machine Suppliers & Manufacturers

Coffee bag formats, valve insertion, and nitrogen flushing

Coffee packaging requires careful attention to gas management and bag format because freshly roasted coffee emits CO₂ for days to weeks after roasting. Packaging without degassing provision will balloon and burst; packaging without adequate oxygen barrier will allow the coffee to stale. Standard coffee bag formats: block-bottom bag (also called flat-bottom or box-bottom bag) — a bag with four sealed vertical seals and a flat, rectangular base formed from the bottom gusset; the premium format for specialty coffee, stand-up on shelf; requires a specialist FFS block-bottom machine or premade bag filler. Side-gusset bag — a flat bag with two side gussets, giving a more rounded cross-section when filled; widely used for ground coffee in retail; produced on a VFFS machine with side-gusset attachment. Stand-up pouch (doypack) — a flat-bottom stand-up pouch with or without zipper; increasingly common for specialty coffee. Pillow bag — the simplest VFFS format; used for commodity coffee in price-sensitive markets. One-way degassing valve: freshly roasted whole bean or ground coffee releases CO₂. A one-way degassing valve (one-way coffee valve) is heat-welded into the bag, allowing CO₂ out but preventing O₂ from entering. Valve insertion is either pre-inserted into premade bags by the bag manufacturer, or inserted inline by a valve-insertion station on the coffee packing machine. Nitrogen flushing: the bag is flushed with nitrogen gas before sealing to displace oxygen, preventing oxidative staling. In vacuum + nitrogen flushing (gas flush), the bag is first evacuated and then back-filled with nitrogen, achieving very low residual oxygen levels (typically under 1%). In nitrogen-only flush, nitrogen is injected into the bag as it is being filled and sealed; less complete but simpler.