The packaging and storage of fresh‐cut fruits and vegetables is quite a challenging task. This is because fresh produce continues to respire and age at an increased rate, even after being harvested due to physiological processes. Freshly cut fruits tend to have a short shelf life ranging from a few hours to 3-4 days. They decay much quicker than processed foods which have been fed with artificial preservatives for enhancing their shelf life. While rigid plastic packaging does manage to protect the fruit from damage and helps it retain its freshness, it cannot extend the shelf life of the fruit by itself.
Modified Atmosphere Packaging (MAP) is a collection of packaging modifications that works to create or maintain a specific type of atmosphere inside a package. This type of packaging controls and slows down the oxidation of fresh fruit and helps prevent the onset of spoilage, off-textures, offensive odors, and discoloration. For instance, lettuce often turns brown or apples becoming gritty in texture once they have been cut. However, by preventing the oxidation process from taking place, the shelf life of the fresh fruits can be extended, and their visual appeal preserved.
In general, oxygen levels of 1 – 5 % are enough to delay the oxidation of fresh produce. At concentrations below 8%, ripening and maturation can be delayed. To achieve these low oxygen levels, a nitrogen gas flush is often used for extending the shelf life of fresh-cut fruits and vegetables. MAP manages the conductive oxygen levels within a package to extend the shelf life of the produce. MAP in trays is being increasingly used for pomegranate arils, mixed cut fruits, cut vegetables, salad mixes, etc.
In addition to gas flushing, there is an increased use of high barrier packaging materials that feature low oxygen transfer rates (OTR). These films (trays and lidding films) have a low oxygen permeability which provides a higher level of protection against oxidation. Breathable films also allow excessive moisture to leave an airtight pack, allowing the produce to remain fresh for longer.
For packers and retailers, the extended shelf life created by MAP means an enhanced product lifespan, wider geographic distribution and brand exposure to a larger audience, ultimately resulting in increased profitability. MAP is also beneficial for consumers. It helps customers enjoy fresh food and enables them to maintain a healthy diet in a convenient manner. Consumers do not have to visit the grocery store repeatedly or worry about their stocked food getting spoilt. Instead, they can stock up on food in larger quantities knowing that the product will remain fresher longer. For society at large, the increased shelf life of fresh produce helps reduce food waste and increases overall food security.
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