Gas scavenging involves injecting a stream of gas (often nitrogen or a nitrogen/CO₂ mixture) into a tray just before closing, in order to drive out oxygen and limit oxidation. Unlike vacuum, this does not involve sucking out the air: it is replaced by an inert gas.
Remember: this is often the fastest method, with equipment costs generally more affordable than a MAP system (vacuum + gas).
Contents
Operating principle
- The product is placed in a tray.
- A nozzle injects gas at high speed to repel oxygen.
- The package is sealed immediately to trap the gas.
Comparison: scanning vs vacuum vs MAP
| Method | Principle | Crushing | Precision | Speed |
|---|---|---|---|---|
| Gas sweep | Chases O₂ by gas flow | Null | Average | Fast |
| Sous-vide | Air extraction | Possible | High | Average |
| MAP | Vacuum + gas injection | Null | Very high | Average |
Benefits
- Speed: very fast method (no vacuum phase).
- Protection: gas can create a “cushioning” effect for fragile products.
- Investment: often more affordable than a complete MAP solution.
- Aesthetics: uncompressed product, natural appearance.
Limits
- Residual O₂: more difficult to reach such low levels than with prior vacuum.
- Repeatability: results may vary depending on the arrangement of the product in the tray.
💡 Gas note
N₂ is used for its neutrality (anti-oxidation); CO₂ can be added for its bacteriostatic effect.
FAQ (SEO optimized)
Does gas scavenging replace MAP?
Not always. Scanning is very fast, but MAP offers more precise and reproducible control of residual atmosphere.
For which products is it best suited?
For fragile or high-speed products, when the aim is to reduce oxygen quickly without crushing the product.
Learn more
Would you like to determine whether gas scavenging is the best compromise (throughput, investment, residual O₂ level) for your products?