Choosing vacuum packaging bags that actually hold a seal
A vacuum bag either holds the vacuum or it does not, and the difference is rarely the machine - it is the film. This guide covers the structures, gauges and finish choices that survive freezing, boiling, sous-vide and long distribution.
What a vacuum bag must do
A vacuum bag is a barrier system under mechanical stress: it is squeezed against sharp bones, frozen, sometimes boiled or sous-vide cooked, and shipped. The three failure points are puncture, seal creep under vacuum, and barrier loss that lets oxygen back in - which defeats the whole point of vacuum packing.
Structures: PA/PE, PA/EVOH/PE and retort
Two-layer PA/PE is the everyday workhorse - nylon gives puncture resistance and the PE seals. Where shelf life matters more, three-layer PA/EVOH/PE adds an EVOH oxygen barrier in the middle; EVOH loses barrier when wet, so for wet or high-moisture products specify structures that protect it. Retort-grade bags add the heat tolerance for 121 C sterilisation. For sous-vide and cooked product, confirm the cooking temperature before we choose the film.
Gauge: buying thickness you do not need
Thickness should follow the hazard: bone-in meat needs a heavier nylon layer, whole fillets do not. Specifying one heavy gauge for everything costs you film area you do not need on 80% of the line. We quote per-structure, so a mixed SKU order with two gauges usually beats a single over-spec gauge.
Seal and surface issues that leak
The seal is where vacuum bags fail most: contamination on the seal area, an under-specified sealant layer, or a bag cut for the product width with no room for a clean seal. Printing is part of it too - heavy ink coverage on the seal path can lift. We design print and seal zones together for this reason.
Testing you can do before bulk
A 24-hour leak test on a sealed sample, a freeze test at your storage temperature and a drop test tell you more than the datasheet. Our samples are cut from production structures so the test you run is the test you ship.
Frequently asked questions
What is the difference between PA/PE and PA/EVOH/PE?
PA/PE resists puncture and seals reliably; PA/EVOH/PE adds an EVOH oxygen barrier for longer shelf life. EVOH loses barrier when wet, so structure choice depends on moisture content.
Can vacuum bags be boiled or sous-vide cooked?
Yes - specify the cooking temperature when ordering; high-temperature bags for sous-vide and retort (121 C) are produced separately from cold-storage bags.
What gauge do I need for bone-in meat?
Bone-in and sharp products need a heavier nylon structure than fillets. Tell us the product and pack weight and we will spec the gauge.
Do you print on vacuum bags?
Yes, up to 10-colour gravure, with print and seal zones designed so ink never crosses the seal path.
How do I test a sample before bulk?
Leak test a sealed bag for 24 hours, freeze at your storage temperature, and drop-test filled bags; samples are cut from production structures.
