Snack pouch barrier requirements: which film each snack needs
Snacks spoil in two ways: fats go rancid with oxygen and light, and crisp things go soft with moisture. Dry, low-fat snacks such as crackers, granola and dried fruit keep well for months in a clear PET/PE pouch with a window; oily nuts and fried chips need metallized film or full foil with no window; freeze-dried food needs foil. Match the film to how the snack fails and how long it sits before it is eaten.
Two numbers behind every barrier spec
Film makers rate barrier with two measurements. OTR, the oxygen transmission rate, is how much oxygen passes through the film in a day; low OTR protects fats and oils from going rancid. MVTR, the moisture vapor transmission rate, is how much water vapor passes through; low MVTR keeps chips crisp and powders loose, and keeps soft snacks from drying out. Both are measured under set lab conditions, so compare like with like when you read a spec sheet.
You do not need to specify the numbers to order a pouch from us. Tell us the snack, the fat content in plain words and how long it needs to last, and we pick the film; you approve the spec.
Film by snack
| Snack | What spoils it | Film we would use | Window? |
|---|---|---|---|
| Crackers, pretzels, granola, dried fruit | Moisture, slowly | Clear or matte PET/PE | Yes |
| Trail mix with nuts | Oxygen on the nuts, moisture | Metallized PET/PE | Small, or none |
| Roasted or oiled nuts | Oxygen and light | Metallized PET/PE, or foil for long shelf life | No |
| Fried chips and crisps | Oxygen, light and moisture | High-barrier chip bag, filled with a nitrogen flush | No |
| Jerky and meat snacks | Oxygen and moisture | Foil laminate | No |
| Freeze-dried fruit | Moisture, fast | Foil laminate | No |
| Popcorn | Moisture | Metallized PET/PE, or a popcorn bag for short shelf life | Optional |
For dry snacks like crackers, granola and dried fruit, a clear PET/PE laminate keeps them crisp for 6 to 9 months. A window is the trade-off to watch on anything with oil in it: light through the window speeds up rancidity, so oily products move to metallized film or lose the window.
The pouches these go in
- Snack pouch. Stand up or flat, clear, matte or metallized PET/PE, with a window, a zipper on sharing sizes and a tear notch on single serves. From 200 units in 10 to 12 business days after proof, 1 ounce to 16 ounces.
- Chip bag. A high-barrier stand up pouch built to hold a nitrogen flush and heat sealed at fill. From 1,000 units in 10 to 12 business days after proof.
- Foil mylar bag. PET, foil and PE, opaque, for jerky, freeze-dried food and anything that must last a long time.
Nitrogen flushing
A chip bag looks puffed because it is filled with nitrogen, not air. Flushing pushes out the oxygen that would otherwise be sealed in with the product, while the film stops more oxygen getting in. The cushion of gas also protects chips from crushing. Flushing happens on the filling line, at your co-packer or in your own facility; our chip bags are built with a film and seal rated for it. For high-fat snacks it is worth doing even on a small run.
What to tell us when you ask for a quote
- The snack, and whether it is fried, oily or dry.
- How long it should last on the shelf and where it is stored.
- Whether you want a window, and how big.
- Fill weight, so we can size the pouch.
- How it is filled and sealed, and whether you flush with nitrogen.
If you need the shelf life proven, run an accelerated shelf-life test with a food lab on the film we propose before you commit to a large run. The nutrition panel prints on the back at the same time as the front; see our nutrition facts guide for the layout rules.
Questions people ask
Do all snack pouches need foil?
No. Dry, low-fat snacks keep well in clear or matte PET/PE with a window. Foil is for jerky, freeze-dried food and snacks that need a long shelf life. Oily nuts and chips sit in between, on metallized film or a high-barrier chip bag.
Will a window shorten shelf life?
For dry snacks like crackers, granola and dried fruit, not meaningfully. For oily nuts and fried chips, yes, because light through the window speeds up rancidity. Move those to metallized film or skip the window.
What do OTR and MVTR mean?
OTR is the oxygen transmission rate, how much oxygen passes through a film in a day. MVTR is the moisture vapor transmission rate, the same for water vapor. Lower numbers mean a stronger barrier.
Do you nitrogen flush the bags?
No. Flushing happens when the bag is filled, at your co-packer or in your facility. Our chip bags are built with a film and seal rated to hold a nitrogen flush.
How is this guide different from the pouch material selection guide?
This guide is about snacks: which film each kind of snack needs and why. The pouch material selection guide explains the films themselves for any product, from coffee and supplements to tea and bath salts.