A vacuum bag is specified by the machine that fills it before anything else. External suction sealers draw air along a textured channel, so they need embossed film. Chamber machines seal smooth, flat film, because the chamber removes the air from outside the bag. Get that one line wrong and the bag will not pull a vacuum, whatever the gauge. After the machine, six inputs decide the rest: contents, fill state, bag format, internal size, print side, and the food-contact market you sell into.
Match the bag to the machine first
The most expensive vacuum bag mistake is rarely a material mistake. It is buying smooth film for an external suction sealer, or paying for embossed film on a chamber machine that never uses the texture.
| Machine type | How it removes air | Film surface it needs | Typical user |
|---|---|---|---|
| External / suction sealer | Air travels out along a channel from inside the bag | Embossed (channel) film, usually one textured side | Home and light commercial freezing |
| Chamber machine | The whole bag sits in a chamber; air is removed from outside | Smooth, flat film | Butchers, restaurants, co-packers, liquids and wet fills |
| Packaging line (thermoform, VFFS) | The machine forms and seals from rollstock | Roll film specified against the machine | Food production lines |
Chamber pouches are specified as smooth film because the chamber, not the bag, creates the vacuum path (Chamber Vacuum Pouch Buyer's Guide). Embossed film exists to give external suction machines a channel to pull through. Each is made for its own machine class, and neither is a substitute for the other.
If you run a forming or form-fill-seal line rather than pre-made bags, the specification changes shape entirely. The rollstock specification guide covers the machine-side fields, and the roll film product page shows the format options.
What PE + PA co-extrusion actually gives you
Foldveil vacuum bags (model FV-FP-VCB) are PE + PA multi-layer co-extrusion. The nylon (PA) layer carries the oxygen barrier and the puncture and tear resistance; the PE layer does the heat sealing. Co-extrusion rather than lamination is what keeps the structure tough while still sealing tightly, and a deep-emboss option covers home vacuum systems. Printing is gravure. You can see the family on the vacuum bags product page.
What that structure means in practice:
- Freezing, chilling and cook applications are within the intended use of the family.
- The usable temperature window, puncture performance and seal strength are not family-level numbers. They depend on the structure selected and are confirmed against an applicable test report.
- Certification and food-contact document scope is verified per factory, material and production run.
That last point is why the quote carries two columns, not one:
| You specify | Confirmed in the quote |
|---|---|
| Machine type and bag format | Structure and gauge that fit that machine |
| Internal dimensions and fill weight | Achievable tolerance on the finished bag |
| Contents and fill state | Food-contact document scope for your market |
| Process (freeze, chill, cook) | Applicable test report for the structure |
| Print and colours | Registration, and which side is the food-contact side |
The eight lines an RFQ needs
You do not need a finished specification to start. These eight lines are enough for a first quotation, and lines 5 and 6 are the ones buyers most often leave out.
- Machine type — external suction, chamber, or a packaging line.
- Bag format — three-side seal, back seal, gusseted, or embossed on one side.
- Internal dimensions — width × length, plus the fill weight you put in it.
- Gauge — the film thickness you have run before, if you know it.
- Contents — dry, moist, liquid, or sharp-edged (bones, shells, frozen blocks).
- Process — freeze only, chilled, hot fill, cook-in-bag, or pasteurised.
- Print — number of colours, coverage, and whether artwork runs full bleed.
- Market and documents — EU or US food contact, and the shelf the product sells on.
If you are changing format — say from smooth to embossed, or from pre-made bags to rollstock — say so on line 1. It changes the answer more than any other line on the list.
Liquids, powders and hot fills
External suction machines pull air from inside the bag, which is also why they pull liquid, powders and crumbs toward the pump. Chamber machines handle wet and liquid fills because the vacuum is created outside the bag. That difference settles the format before thickness is even discussed.
For hot fills and cook applications, two things change:
- The seal has to survive the process temperature, not just the filling line.
- Headspace and fill level matter more, because product sitting in the seal area is the most common cause of a leaker.
We do not publish a single temperature ceiling for vacuum bags, because the answer depends on the structure, the seal and the load. Give us the process and we confirm both the structure and the supporting test report in the quote.
Vacuum packaging is not shelf-stable packaging
This part belongs in your own product validation, not in the bag specification.
Vacuum packaging removes oxygen, which is why it is also called reduced-oxygen packaging (ROP). Removing oxygen slows some spoilage organisms and slows oxidation, but it favours others, and it does not make a perishable product shelf-stable. Both Michigan State University Extension and K-State Research and Extension treat vacuum-sealed food as a temperature and process question rather than a packaging question (MSU Extension, K-State Research and Extension, MF3639).
Practically: the bag controls the atmosphere and delivers the seal. Your process and your validation establish the shelf life, and any shelf-life claim belongs on your documentation, not on ours.
Where leaks actually come from
Most vacuum bag failures are not film failures. They start at the seal:
- Product or liquid in the seal zone
- Wrinkles or folds across the seal bar
- Overfilling, so the bag mouth cannot lie flat
- Sharp edges poking the film from inside
- The wrong film surface for the machine
Specifying gauge solves one of those five. Specifying the format, the fill level and the mouth width solves the rest — which is why we ask for a product sample on new projects. The same discipline applies across pouch formats, and the packaging test plan sets out how drop, seal, puncture and migration testing are structured when you need evidence rather than assurance.
Documents: what comes with the quote
For food-contact bags, the useful question is not "are you certified" but "what is certificated, for which factory, material and production run". Our answer is the same every time:
Certification and test-document scope is verified for the selected factory, material and production run; available certificate numbers are shared with the quote.
If your market is the EU or the US, the food-contact document pack guide lists what to request and why. Barrier figures follow the same rule: an oxygen or moisture value is only meaningful against a named structure and test method, which is what the OTR and WVTR guide walks through.
Sizes, cartons and freight
Pre-made vacuum bags ship flat and dense, which makes them one of the friendlier formats to freight. Rollstock behaves differently, because roll diameter and core size drive the carton dimensions. Rice and grain brands running vacuum brick packs meet the same trade-off in a different bag format.
If you are calculating landed cost, the container loading math guide shows how carton count, CBM and container fill interact — worth running before you lock a bag size, because a small change in bag dimensions moves cartons per container.
Next step
Send the machine type, the internal bag size and the fill weight. Those three lines are enough for us to recommend a format and put a quotation together. If you already have a bag running and want it matched or improved, send a sample along with the process it goes through.