Vacuum packing has become a technique for preserving food quality, extending shelf life, and maintaining the original taste of perishable items.
Research from the Canadian Food Inspection Agency highlights that vacuum-packed items can reduce bacterial growth by as much as 98% compared to non-sealed methods.
By limiting exposure to moisture and airborne contaminants, sealing inhibits the growth of aerobic bacteria, such as Listeria and Salmonella, which are leading causes of foodborne illness in Canada.
A recent report from the Food Packaging Forum accentuates the increasing adoption of packing in both commercial and household settings, predicting a 5.8% Compound Annual Growth Rate in the global market between 2022 and 2027.
Manufacturers and consumers are now turning to this method as part of a broader strategy to combat waste, which costs the country an estimated $31 billion annually.
What is Vacuum Packing?
It is a food preservation method that removes air from a package before sealing it, creating an environment that slows down spoilage and oxidation. Sealed goods can last 3 to 5 times longer than those stored using traditional methods like plastic wrap or Tupperware.
What Are Its Benefits?
Prolongs Storage Life
- By eliminating air concentration inside the package to as low as 0.5%, this inhibits the growth of aerobic microorganisms such as Pseudomonas and Staphylococcus aureus.
- These bacteria require oxygen to reproduce, and without it, their metabolic processes slow down, effectively delaying spoilage.
Preservation of Sensory Qualities
These qualities are taste, texture, and colour. This is beneficial for high-fat products like meats and dairy, which are prone to oxidation—a chemical reaction that causes rancidity.
- This method reduces the risk of oxidative rancidity by creating a low-oxygen environment, thereby maintaining the product’s flavour profile over time.
Protection Against Frost Damage
Burn occurs when frozen food is exposed to air, causing dehydration and the formation of ice crystals on the surface of the product. This results in undesirable changes in texture and flavour.
Reduced Waste
Canada faces a waste issue, with an estimated 58% of all food produced in the country being lost or wasted. Airtight sealing is increasingly recognized as a viable solution for the industry.
Improved Food Safety
Sealing minimizes bacterial growth and delays spoilage. By removing air, this inhibits the growth of harmful microorganisms such as Listeria monocytogenes and Salmonella enterica, which are known to thrive in airy environments.
How It Works
Loading it into the Bag or Container
The item is placed inside a vacuum bag or container made from air-impermeable materials, such as multi-layered plastic films. These are designed to prevent the passage of gases, including oxygen and moisture vapour.
Air Removal
A sealing machine, either chamber or external suction type, is used to evacuate the air from the container. Chamber machines are used in commercial applications, while external suction machines are more common for household use.
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Chamber Machines |
In this system, the entire bag or package is placed inside a chamber. The atmospheric oxygen inside the chamber and the package is simultaneously evacuated. Efficient for achieving a uniform seal. The air pressure is reduced to a very low level (below 10 mbar), and is then heat-sealed. |
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External Suction Machines |
In this system, the bag is placed outside the machine, and the machine is drawn only from the bag. While external suction machines are less powerful than chamber machines, they are effective for smaller-scale applications. |
Sealing the Package
Once the air has been removed, the bag or container is sealed using heat, creating a strong, airtight bond. This is achieved through a heat-sealing strip that melts the plastic layers together, ensuring that no air can re-enter the package.
- Heat-sealing is an important step as even a small leak in the package can compromise the vacuum environment. Allows oxygen permeability and moisture to re-enter.
What Are The Materials Used?
Nylon/Polyethylene (PE)
Nylon provides a high barrier against oxygen, while polyethylene offers flexibility and heat-sealability. This combination is commonly used in bags and films.
Polyester (PET)
PET films are used for their durability, clarity, and high resistance to puncture. Suitable for packing sharp or hard items such as bones in meat products.
EVOH (Ethylene Vinyl Alcohol) Coated
EVOH offers great gas-barrier properties. They are laminated onto another plastic film package to enhance oxygen impermeability, particularly in long-term storage applications.
Best Practices for Packing Different Food Types
Meats and Poultry
For these items, the process should ensure a near-complete removal of oxygen to prevent lipid oxidation. High-barrier pouches or bags, made from multi-layer laminates, provide effective protection against oxygen permeation.
- They should be sealed and refrigerated at temperatures below 4°C (39°F) for short-term storage or frozen at -18°C (0°F) for long-term storage.
- For optimal results, airtight meats can be kept in the freezer for up to 2-3 years.
- Pre-freezing the product slightly helps minimize the "squashing" of the meat fibers during the process.
Fish and Seafood
Fatty fish (salmon and mackerel) contain omega-3 fatty acids that are prone to oxidation, which can result in the rancidity of vacuum-sealed food. Sealing slows this process, thereby preserving the freshness and preventing off-flavours associated with lipid oxidation.
- The growth of Pseudomonas and Vibrio species is limited in the low-oxygen environment created by the space.
Fruits and Vegetables
Airtightening leafy vegetables like spinach, lettuce, and kale can extend their shelf life from a few days to over a week by minimizing oxygen exposure and preventing wilting. Pre-blanching (brief exposure to boiling water followed by rapid cooling) before packing can inactivate enzymes that cause spoilage.
- Vegetables like broccoli, cauliflower, and cabbage release ethylene gas during storage, which cause the bag to inflate and compromise the seal.
- For these vegetables, it should be done with caution, or alternative packaging methods such as modified atmosphere packaging (MAP) may be used, where gases like nitrogen are introduced to the sealed environment.
- For fruits, ensure that they are dried or pre-treated to minimize moisture.
Dry Goods and Snacks
Grains, pasta, coffee beans, and snacks benefit from airtight skin packaging as they prevent moisture absorption and staleness.
- For dry goods, ensure the vacuum sealer creates an airtight sealing bar to protect against moisture ingress, such as multi-layered barrier bags.
Cheeses
Cheeses, particularly semi-hard and hard varieties, benefit from this due to their susceptibility to mold growth and moisture loss during storage.
- Moulds are aerobic organisms, meaning they require oxygen to grow. Vacuum sealing prevents its growth by removing oxygen.
Spices and Herbs
These items are sensitive to air, light, and moisture, all of which degrade their flavor over time. With this method, they retain their flavours much longer than those stored in traditional ones, as they are protected from the oxidizing effects of air exposure.
- This is important for spices like paprika, chili powder, and turmeric, which can lose their intensity over time if not properly stored.
Optimize Your Preservation with Patek Packaging
Vacuum packing is a proven and effective method for preserving meal quality and extending shelf life by reducing air exposure, controlling moisture, and preventing freezer burn. By inhibiting spoilage such as oxidation and microbial growth, meals retain their flavour, texture, and nutritional value far longer than conventionally stored products.
Whether you're sealing raw meats to prevent freezer burn, keeping delicate seafood fresh, or preserving the crispness of nuts and dry goods, this method is suited for both domestic and commercial use.
Patek Packaging Richmond offers vacuum bags and films, made from multi-layered nylon/polyethylene (PE) and polyester, that provide the highest level of oxygen and moisture barrier protection. These are best for storing a wide range of perishable goods under refrigeration or freezing conditions.
Frequently Asked Questions
What are the recommended vacuum levels for different food types?
A lower level (around 70-80% of the air removed) is best for delicate items like fruits to avoid crushing. A higher level (up to 99% of the air removed) is ideal for meats and poultry to maximize shelf life and prevent spoilage.
What are the ideal packaging materials for vacuum packaging?
High-barrier films from multi-layer laminates, including polyethylene, nylon, and aluminum foil, protect against oxygen and moisture. Use materials with high puncture resistance and gas barrier properties for long-term storage.
For instance, bags with thicknesses of 3-5 mils (0.076-0.127 mm) are commonly used for both commercial and home applications.
Can vacuum packing be used for sous-vide cooking, and how?
Yes. The bag prevents water from entering the item, ensures even cooking, and enhances flavour infusion. For sous-vide, use heat-resistant bags to withstand temperatures up to 85°C (185°F). Proper sealing and bag quality are imperative to avoid leaks and ensure consistent cooking results.