Modified Atmosphere Packaging (MAP) refers to technologies used to control the atmosphere inside packaging of perishable foods. The most common objectives are to extend shelf life, maintain product quality, or enable controlled ripening processes. This can involve completely substituting the air inside the package with a less reactive gas or creating a controlled ventilation system within the packaging.
Modified Atmosphere Packaging encompasses a broad array of applications and technologies. In this chapter, we will delve into some key distinctions and explanations of these technologies
In the world of food packaging, maintaining product quality while extending shelf life is of the utmost importance. In MAP Packaging two methods often employed are Modified Air Packaging (also known as Breathable Packaging) and Air-Substitution, each with its unique approach and benefits.
This is primarily achieved through microperforations in the packaging material, which are often laser-created. This method is particularly beneficial for products that emit gases as they ripen, such as fruits and vegetables.
moreBy allowing these gases to escape and fresh air to enter, breathable packaging helps in controlling the ripening process and preventing spoilage. It's ideal for products that require a certain level of moisture and air exchange to maintain freshness.
In gas-flushed MAP systems, maintaining an adequate MAP headspace ensures that the modified gas mixture remains stable and effective throughout the product’s shelf life.more
This technique is especially useful for products that are sensitive to oxygen, including meat, dairy products, and some prepared foods. It helps in preserving taste, texture, and nutritional value over a longer period.
While Air Substitution is often used when vacuum packaging is not possible there is also a combination of both called “Active Vacuum”.
When it comes to breathable packages, there are two main options to consider: Barrier Packaging Films and Porous Films. Each type has its own set of characteristics and applications, making them suitable for different packaging needs.
They are usually made of low-density polyethylene (LDPE), aluminium foil (AL), or polypropylene (PP) and consist of multiple layers to allow for a certain degree of permeability.
moreTheir main advantage is the protection against intrusion of moisture, liquids or insects into the packaging. However this comes with a significantly higher price while often the same atmospheric requirements can also be achieved with porous films.
Porosity is usually achieved by laser perforation, which is a highly flexible production method. Thus many different characteristics and degrees of breathability can be achieved with mere software changes.
moreIn some cases, especially many fruits and vegetables there is no alternative to porous films as the required degree of gas exchange and the desires gas mixture cannot be achieved with special films.
For meals that are packaged hot, Modified Atmosphere Packaging is essential to prevent spoilage and maintain quality. By allowing the escape of steam and controlling the internal atmosphere, MAP ensures that meals retain their desired texture and taste.
Snack foods and processed items require protection from moisture and air to maintain crispness and prevent spoilage. MAP helps in preserving the quality and extending the shelf life of these products.
MAP is vital in preserving the texture and freshness of bakery items. By controlling the oxygen and moisture levels, it prevents the growth of mold and bacteria and reduces staling.
MAP is particularly crucial in preserving the color, texture, and freshness of meat, poultry, and seafood. By reducing the oxygen level, it inhibits the growth of aerobic bacteria and prolongs shelf life.
In beverages like coffee and tea, MAP plays a role in preserving flavor and aroma by preventing oxidation.
Breathable Packaging extends the life of cut flowers and potted plants. By controlling the ethylene gas within the packaging, MAP slows down the aging and wilting process.
Cheese, yoghurt, and other dairy products are sensitive to microbial growth and oxidation. MAP helps in extending their shelf life by creating an optimal gaseous environment.
MAP technology is also employed in microwaveable packaging to allow steam to escape during cooking. This prevents pressure build-up and ensures even cooking of the food. Additionally, laser scribing techniques can be used to create specific contours for effective steam venting.
Laser perforation is a key enabler for breathable Modified Atmosphere Packaging (MAP), where the packaging must allow for a controlled gas exchange. This is particularly important for fresh produce, flowers, or ready-to-eat meals that continue to respire after packaging.
Unlike air substitution methods—such as gas flushing, which replace the atmosphere entirely—breathable MAP requires films that permit selective gas permeability. Laser technology enables highly precise and consistent microperforations that define how much oxygen and carbon dioxide can enter or leave the package.
Through software-controlled settings, hole size, density, and pattern can be adjusted to match the specific respiration rates of different products. This flexibility makes laser perforation a highly adaptable and efficient method, especially for applications where off-the-shelf packaging films do not offer the needed performance.
In short, laser perforation allows standard films to be customized for breathable MAP, improving shelf life and product quality without the need for complex multilayer materials.
MLT offers solutions to create porous films during the converting process as well as inline machines that can be directly integrated in the packaging process. Our laser technology facilitates a combination of processes such as perforating, scoring, and laser cutting, all in one streamlined operation.
Our expertise lies in the high-speed laser processing of moving materials. We pride ourselves on our exceptional flexibility, tailoring solutions to meet the unique needs of your production process. Our commitment extends to global integration and service support, ensuring your operations run smoothly and efficiently.
Ideal for film manufacturers, film converters and the food industry, specializing in the laser perforation of film and packaging materials.
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A versatile solution for film converting and refining flexible packaging materials, offering laser perforation, cutting, and scoring of films and paper within one machine.
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Optimizes air permeability of packaging films through microperforation for Modified Atmosphere Packaging applications, extending the freshness of perishable items.
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Of course, shelf life always depends on multiple factors such as product type, ripeness, temperature, and humidity. Laser-perforated packaging works best when it complements these existing conditions with a well-matched gas exchange rate.
Depending on the application, CO₂ can either be a desired component to increase shelf life—or an unwanted byproduct that needs to be removed.
In gas flushing applications, CO₂ is intentionally introduced into the packaging atmosphere—often in combination with nitrogen—to inhibit the growth of aerobic bacteria and mold. This is particularly effective for meat, dairy products, and baked goods. By increasing CO₂ levels and reducing oxygen, the shelf life of these products can be significantly extended.
In contrast, in breathable MAP systems—used for respiring products like fruits, vegetables, and flowers—CO₂ is naturally produced by the product itself. In these cases, it is essential to allow the excess CO₂ to exit the packaging through microperforations, in order to avoid spoilage, off-flavors, or physiological damage. Here, the role of the packaging is to regulate gas exchange, not to trap CO₂.
The packaging strategy must therefore be tailored:
Gas flushing: When more CO₂ is beneficial and actively introduced.
Breathable packaging: When excess CO₂ must be allowed to escape.
Understanding the product’s biology and respiration rate is key to choosing the right MAP method and CO₂ strategy.
Thus the use of conventional films with perforation is usually cheaper than the use of special porous films.
There are scenarios where the use of non-porous films is necessary. These films provide a controlled barrier against environmental factors and effectively block the entry of liquids, dirt, and small insects. The barrier properties of non-porous films make them suitable for applications where protection from external contamination is crucial.
Nitrogen (N2):
Nitrogen is an inert gas and is primarily used for its non-reactive properties. It does not react with foods and thus, helps in preventing oxidation and spoilage. Nitrogen is often used to displace oxygen in the packaging, reducing the rate of aerobic microbial growth and oxidation.
Carbon Dioxide (CO2):
Carbon dioxide is effective in inhibiting the growth of bacteria and mold. It is often used in packaging of products like meat, poultry, and cheese. However, high concentrations of CO2 can dissolve in fats and water, leading to product quality changes, so its levels need to be carefully controlled.
Oxygen (O2):
While oxygen is generally removed to prevent spoilage and oxidation, it is sometimes used in controlled amounts in MAP.
