What is Modified Atmosphere Packaging (MAP) and Should You Consider It?
Fresh. Natural. Preservative-free.
These buzzwords used to describe food and beverage products are no longer just a passing trend but are becoming the standard. Consumers demand fresh products that involve minimal processing, yet also desire them to have extended shelf lives. Busy consumers don't have time to stop at the grocery store every day, and suburbanization has made the convenient neighborhood market a thing of the past.
Food and beverage producers must supply their products to an increasingly globalized market, necessitating longer shelf stability for their products. Because of this, modified atmosphere packaging (MAP) has become increasingly popular for extending the shelf life of fresh items. So what is MAP and how do you know if it's right for your product?
What is MAP?
According to the FDA, modified atmosphere packaging "involves either actively or passively controlling or modifying the atmosphere surrounding the product within a package made of various types and/or combinations of films." One of the first applications of this technology was introduced by McDonald's, which used modified atmosphere packaging of lettuce in bulk-sized packages to be distributed to their retail outlets. This enabled them to package perishable products in bulk that would be shelf-stable for longer periods of time.
A modified atmosphere can be defined as one that is specially created by altering the natural distribution and makeup of gases in the air. When applied to packaging, this involves modifying or controlling the makeup of gases contained within each package to provide optimal conditions for increasing the shelf life and reducing oxidation and spoilage of perishable food and beverage products.
There are two different kinds of modified atmosphere packaging: Passive and active. The FDA defines active MAP as "the displacement of gases in the package, which is then replaced by a desired mixture of gases" and passive MAP as "when the product is packaged using a selected film type, and the desired atmosphere develops naturally as a consequence of the products' respiration and the diffusion of gases through the film."
What are some examples of MAP?
1. Gas flushing. For food and beverage products, nitrogen is most often used to decrease the amount of ambient oxygen within that package, as this gas can increase the rate of product spoilage. Nitrogen gas flush is a MAP option that many of our clients use. This can occur inside the package itself as well as in the steps leading up to packaging, like inside the filling apparatus. During this process, nitrogen gas is actively pumped in to displace oxygen. The FDA reports that this accomplishes three things:
- Displacement of oxygen to delay oxidation
- Decreasing the growth of aerobic spoilage organisms
- Acting as a filler to maintain package conformity
2. Barrier packaging films. Choosing specific packaging films that provide increased protection is another example of modified atmosphere packaging. This is accomplished by using barrier packaging films that provide decreased permeability to moisture and oxygen, such as low-density polyethylene (LDPE), polyvinylchloride (PVC) or polypropylene (PP), according to FDA. New on the market are 'smart' packaging films that can contain indicators of temperature, leakage, food quality, and more.
3. Scavenger or desiccant packs. Another example of MAP is the addition of an oxygen scavenger or desiccant pack to your packaging. According to Bakery Online, these small sachet type packages often contain a mixture of iron powder and ascorbic acid, and sometimes activated carbon. These ingredients act as catalysts or activators, absorbing ambient moisture and oxygen, thereby removing it from the interior of the packaging that houses the perishable product.
4. On-package valves. One-way valves added to the exterior of packaging are another example of MAP. These special valves can be added to rollstock film during the packaging process. One-way valves allow certain gases to escape from the package without allowing any outside gases in. This is often done to release pressure created from gases the products release, but can also be done to allow air to escape from packages for better stacking and palletization.
How does modified atmosphere packaging protect food?
Largely, modified atmosphere packaging technologies protect fresh food by decreasing its exposure to oxygen. Oxygen leads to oxidation, which can cause discoloration, spoilage, and off-flavors and textures. By decreasing or controlling the amount of oxygen present in a package, the food product remains fresher longer, extending its shelf life and ensuring it remains attractive to consumers.
Modified atmosphere packaging technologies are especially useful for fresh-cut fruits and vegetables, which can degrade in a matter of hours when exposed to oxygen. H. Louis Cooperhouse of Food Safety magazine reports that MAP in the fresh-cut produce category represents one of the fastest growing categories of modified atmosphere packaging usage. "New fresh-cut fruit offerings that incorporate MAP and other technologies are now available, including pre-cut honeydew, pineapple, and mixed fruit salads with a 10- to 14-day shelf life, and pre-sliced apples with a three- to six-week shelf life," says Cooperhouse. These products are increasingly being offered at grocery stores to consumers who desire fresh, natural food without preservatives but also value the convenience of an extended shelf life.
Who uses modified atmosphere packaging?
After coffee beans are roasted, they release carbon dioxide. Without MAP, roasters must allow the beans to cool and degas before packaging because the build-up of CO2 can cause the package to burst. However, this can result in beans reaching the consumer that are not at the utmost level of freshness. Staling can occur quickly if beans are exposed to the elements for too long. As a result, many specialty coffee roasters utilize MAP in the form of one-way valves (pictured at left) that allow for the release of carbon dioxide from the coffee bag without letting any ambient environmental gases or contaminants in. This allows for packaging coffee beans at the height of their freshness, preserving the flavors and quality that consumers desire.
Producers of fresh fruits and vegetables
Fresh-cut fruits and vegetables will often use many forms of modified atmosphere packaging, including nitrogen gas flush and the use of specific barrier packaging films. Fresh produce is especially sensitive to environmental conditions and oxidation, and thus often must utilize more than one tactic to preserve their freshness and stall perishing. Nitrogen gas flush will displace oxygen within the package, thereby decreasing oxidation which leads to discoloration, off-flavors, and spoilage. Barrier packaging films double down on preservation efforts by keeping excess moisture, ambient gases, and contaminants out of the package while simultaneously maintaining the proper atmosphere inside the bag.
Specialty snack producers
With the increase of 'snackification', many on-the-go consumers no longer have set meal times and prefer to snack throughout the day on healthful foods. To maximize convenience to consumers but still offer the natural, preservative-free products they desire, snack producers increasingly use barrier packaging films to protect the freshness of their product and extend shelf life. While barrier films usually cost more, consumers by and large are happy to pay a premium for convenient snack products that will last longer and result in less product waste.
Pharmaceutical and nutraceutical manufacturers
The pharmaceutical and dietary supplement industries will often employ oxygen scavenger or desiccant packs to decrease the amount of moisture or oxygen in the interior of product packaging. You have probably seen these small packs inside packages of pain relievers or vitamins, labeled 'do not ingest'. These small packs extend the shelf life of these important products, allowing for consumers to store them in their medicine cabinets for longer periods of time.
How to get started with MAP
Viking Masek has many years of experience designing fully integrated modified atmosphere packaging solutions for many industries. But first, we need to nail down some details. Start planning your modified atmosphere packaging system with our free Project Scope Planner: