How does heat sealing work in food packaging?
Date
3 February 2026
Category
Reading time
1 Minute
Heat sealing is one of the most widely used technologies in modern food packaging. Reliable, safe and versatile, it allows you to package fresh, ready-made or semi-finished products ensuring hygiene, protection and a longer shelf life. More and more food companies, from pasta factories to dairies, from delicatessens to ready-made meal manufacturers, are choosing this technique to improve the efficiency, presentation, and safety of their packaging. But how exactly does heat sealing work?
What’s heat sealing in food packaging
Heat sealing is a process that joins a container (usually a PP, PET or multi-layer material tray) to a heat sealable film through the controlled application of heat and pressure. This allows the package to be closed tightly, protecting the food from external contamination and maintaining its organoleptic properties.
The result is a safe, tidy and durable packaging, ideal for both the refrigerated counter of the large-scale distribution and for take-out in the restaurant.
How the heat sealing process occurs
The operation can be summarized in four main steps:
1. Preparing the tray
The tray is filled with food (fresh pasta, meat, vegetables, poke, ready meals, cheeses, etc.) and placed in the heat sealer.
2. Application of film
A specific film — usually PET, PP or barrier material — is unfolded over the tray, ready to be sealed.
3. Pressure and heat
The machine lowers a heated plate which exerts:
- controlled heat,
- constant pressure,
- a predetermined contact time.
The film adheres to the surface of the tray creating an airtight seal.
4. Finishing and cutting
The machine cuts out the excess film and releases the sealed tray, ready for labelling, secondary packaging and distribution.
Heat sealing with modified atmosphere (MAP / ATM)
One of the most advanced versions of heat sealing is modified atmosphere packaging, known as MAP or ATM. Before sealing, the air in the tray is replaced with a mixture of food gases (usually oxygen, nitrogen and CO₂) which:
- slows microbial growth,
- maintains color and freshness,
- prolongs shelf life.
It’s the preferred technology for fresh pasta, meat, fish, over-the-counter products and gastronomy.
What advantages does heat sealing offer?
Heat sealing is chosen because it guarantees:
- High hygiene safety
- Airtight and durable closure, ideal for transport and storage
- Impeccable presentation and product visibility
- Reduction of waste thanks to the extension of the duration
- Compatibility with sustainable and recyclable materials
- Customization options (graphics, formats, thicknesses)
GoPack offers a wide range of certified heat sealable trays, specific films and solutions with EVOH barrier or bio materials.
GoPack: partner for a professional heat sealing
Choosing heat sealing is only convenient when combined with quality materials.
GoPack provides:
- Heat-sealable trays in PP, PET, R-PET, bio and multilayer
- High performance heat sealable films
- Free samples for machinery testing
- Technical consultancy to identify the most suitable solution for the product
Heat sealing is a simple yet powerful technology, capable of ensuring safety, freshness and professionalism. With GoPack’s solutions, every product is protected, valued and ready to reach the consumer in the best way.
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