Modified Atmosphere Packaging as a Tool to Improve the Shelf Life of Fruits
MANZOOR AHMAD SHAH1*, SAJAD MOHD WANI2,
SHAIQ AHMAD GANAI2, SHABIR AHMAD MIR3, TARIQ AHMAD4, and B. N. DAR4
'Department of Food Science & Technology, Government PG College for Women, Gandhi Nagar Jammu, Jammu and Kashmir, India
- 2Division of Food Science and Technology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Jammu and Kashmir, 190025, India
- 3Department of Food Science & Technology, Government College for Women, Srinagar, Jammu and Kashmir, India
- 4Department of Food Technology, Islamic University of Science and Technology, Awantipora, Jammu and Kashmir, 192122, India
Modified atmosphere packaging (MAP) is widely to preserve the freslmess and extend the shelf life of fruits. It involves the modification of gases around the fruit inside the package. The gas composition inside the package is different from normal air composition and thus prevents the deteriorative reactions in the packed fruit and maintains the quality and improves the shelf life of fruit. MAP reduces the respiration rate, ethylene production, ripening, weight losses, physiological disorders, and decay-causing pathogens. It has also been beneficial for preserving bioactive compounds of fruits. The most common gases used in MAP of fruits are CO,, 02, and N2. Several types of packaging materials, differing in their physical properties such as permeability, have been used in MAP of fruits. MAP has been successfully used for whole fresh fruits, fresh-cut fruits either alone or in combination with other treatments.
The world fruit production has reached 865,876,405 tons in the year 2016 (FAOSTAT, 2017). The fruit consumption has been increased because of the growing awareness about their health benefits. They are an important source of carbohydrate, protein, organic acids, dietaiy fiber, vitamins, minerals, and other bioactive compounds and are considered as an integral part of human diet. Hence fresh fruits have been always a good market demand. However, due to their perishable nature, they have a short storage life and loss their freshness shortly after harvest. The high postharvest losses and high market demand have led to the development of various technologies for preservation of fruits (Mangaraj and Goswami, 2009).
Several technologies have been developed and successfully applied to preserve fruits. Modified atmosphere packaging (MAP) is one of such technologies that have been most widely used for preservation of fresh fruits. MAP is a packaging technology that modifies or changes the gas composition suiTounding the food product inside the package. The composition of air inside the package is different from normal air composition. This prevents the deteriorative reactions in the packed food and thus maintains the quality and increases the shelf life of food. MAP decreases the respiration and ethylene production, delays ripening and softening, reduces weight losses, and decreases the physiological disorders and decay-causing pathogens (Ahvenainen, 1996). The literature suggests that MAP has been beneficial for preserving bioactive compounds of fruits (Amoros et al., 2008; Singh and Rao, 2005).
Different types and combinations of gases such as CO„ O,, and N, have been used in MAP of fruits, depending on the type of fruit. Some authors have also used argon and nitrous oxide (Rocculi et al., 2004, 2005). MAP depends on the physical properties of the packaging film that determine permeability to different gases, moisture and on the respiration and transpiration rate of the product (Petracek et al., 2002). Several types of packaging materials have been used in MAP of fruits. These include low density poly ethylene (LDPE), polypropylene (PP), polyvinyl chloride (PVC), BOPP (bi-axially oriented polypropylene), polyolephynic film (PO), Xtend® film (XF), Polylid® film, and so on.
The modification of gas composition inside the package may be achieved either actively or passively. Active modification can be done by replacing the air with a desired gas composition. This process is known as gas flushing. In passive modification, no gas flushing is done but the atmosphere inside the package is changed as a result of food respiration and/or the microbial activity associated with the food. Another type of MAP is vacuum packaging which involves the complete removal of air from the package (Bodbodak and Moshfeghifar, 2016). The other types of MAP are equilibrium modified atmosphere packaging (EMAP) and modified atmosphere and humidity packaging (MAHP). The EMAP can be achieved by using special type of packaging films whose gas (CO, and O,) permeation rates match the respiration rates of the fruit (Del-Valle et al., 2009; Ahnenar et al. 2007). The equilibrium concentrations are vital for fruit quality since exposure of fruits to high carbon dioxide levels may result in physiological damage and exposure to too low oxygen levels may lead to anaerobic respiration and the development of off-flavors (Del-Valle et al., 2009).
MAHP is a type of MAP in which the humidity inside the package is modified in addition to gas composition, so as to control the amount of transpiration (Jalali et al., 2017). Perforated films are commonly used in MAP of fruits. These perforated films allow exchange of gases at higher rates than conventional packaging films (Gonzalez et al., 2008). The size of the perforations may vary from microperforations to macroperforations.