MAP Gases – Protecting and Preserving Food Naturally

To appeal to today’s discerning customers, food needs to be minimally processed, attractively packaged, and healthy.

Whether your product is a rich-bodied wine, a bag of gourmet nuts, or a specially blended olive oil, natural deterioration and spoilage threaten freshness and shelf life.

In addition, external factors like temperature, hygienic conditions, gas atmosphere, and processing methods will affect the quality of the product you deliver to the market.

Packaging processes are critical to:

• Guaranteeing safe, healthy products for the consumer
• Reducing spoilage
• Extending shelf life
• Increasing the profitability of your products

Innovative companies are moving away from packaging methods that physically or chemically alter the food or beverage in order to preserve freshness. Instead, they employ MAP – Modified Atmosphere Packaging, a natural shelf-life enhancing method that maintains quality while retaining the original taste, texture, and appearance.

What Makes MAP Such a Popular Choice

MAP is today’s most effective method of food preservation and protection. It uses liquid nitrogen or a gas mixture in modified atmosphere packaging to retain the original taste, texture, and appearance of the product being packaged.

MAP gas mixtures usually consist of nitrogen (N2) and carbon dioxide (CO2), though they can contain other gases such as nitrous oxide, argon, or hydrogen.

Each of the gases has unique properties that interact with the foods or liquids to help retain their original properties. The gases can be mixed specifically for each type of product or used individually.

Nitrogen is an inert gas that is primarily used to prevent oxidation by pushing out ambient air during packaging to prevent oxidation. Due to its low solubility in water, nitrogen also helps to maintain internal pressure to prevent package collapse, which reduces the amount of outer packaging required and facilitates product transport and stocking.

We recommend using liquid nitrogen over gas. LN2 vaporizes quickly and increases in volume 700 times, so it’s the most effective way to force oxygen out while achieving container rigidity and using far less nitrogen in the process.

Carbon dioxide helps to inhibit microbial activity by dissolving into food’s liquid and fat phase and reducing its pH value. It also causes changes in permeability by penetrating biological membranes.

Packaging with MAP Gases

After the product is placed in the package, the air in the package is replaced with a modified atmosphere. The methods used to modify the atmosphere include:

• Gas Flushing: Replaces the air inside a package with a continuous gas stream that dilutes the air surrounding the product before the package is sealed.
• Vacuum Extraction:  A process that first extracts air from the package, and then replaces it with an injection of the desired gas mixture. Because almost all of the air is removed, the product is less likely to be affected by residual oxygen levels in the packaging than the gas flushing method.

How It Works

Liquid nitrogen is delivered to the doser by a vacuum-insulated hose and flows to the dosing head, which delivers the precise amount of liquid nitrogen or gas mixture to the product. A wide range of packaging systems like tray sealers, deep drawing, vacuum chambers, and bag sealers can be adapted to MAP technology.

The Benefits of MAP

• Preserves natural freshness while retaining more of the original taste, texture, and appearance of the food.
• Extends product shelf life by days or even weeks.
• Appeals to consumers who want food with fewer preservatives.
• Simplifies packaging by eliminating the need to list many preservatives.
• Reduces outer packaging costs by maintaining package rigidity.
• Extends your market reach since perishable products can be transported further with extended shelf life.
• The product stays on shelves longer so deliveries could be made less frequently.
• Less product spoilage and fewer product returns.

MAP is successfully employed with many types of packaging materials and packaging processes.

WestAir: Exclusive Distributors of Chart Industries’ Liquid Nitrogen Dosing Systems

You can look to WestAir Gases & Equipment to help you with process & system analysis and design for all Liquid N2 dosing applications.

Download the FreshPak Brochure

Call WestAir at (866) 937-8247 for questions on applications ranging from:

• Pressurization in Packaging
• Product Preservation
• Freezing
• Modified Atmosphere Packaging
• Aseptic Containers

Questions? Head over to our Contact Us page.

Dan Fairchild