As a healthy option and for convenience I will sometimes buy ready-to-eat fruits and vegetables while shopping. As you consider your choices, in the one-hour lunchtime, it seems better and healthier to get a pack of watermelon or fruit salad than fried chicken or a burger. There are options galore, packaged conveniently in Styrofoam trays and cling wrap, clam shells or even the cute smoothie cup. Typically, these are indeed healthier and better options.

But sometimes it’s an epic fail.

Unfortunately, at times like this we sacrifice taste and quality in the name of convenience or the perpetual on-the-go lifestyle. Ever taken a bite of your watermelon (or other ready-to-eat fruits) and it tasted like the supermarket? Yuck! Why is that, though? Why do cut fruits taste like the environment where you purchased them? Why do you see the edges of ready-to-eat fruits and vegetables becoming brown? Why does mould grow on the “peg” of cheese that is stored in the refrigerator? It is linked to the nature of the food and the choice of packaging material.

Packing material has many roles in the food industry, including marketing, protection and preservation. For marketing, it is the labelling aspect that is related to food safety. In the book HACCP: Essential Tool for Food Safety, it states:

“Packaging design and materials should provide adequate protection to minimise contamination, prevent damage, and accommodate proper labelling. Packaging material must be non-toxic and not pose a threat to the safety and suitability of food under the specified conditions of storage and use.”

Therefore, packaging material is to protect food from tampering and contamination during processes such as storage and sale. Since there is a wide range of packaging material, the selected choice depends on the type and nature of the food. It determines the functionality of the package, taking into consideration its first purpose which is preservation and protection of food.

Types of food packaging

• Rigid packages — cans, jars, trays

• Flexible packages — vacuum bags, squeeze tubes, cling wraps

• Semi-flexible packages — tetra packs, boxes

The intended function of the packaging material will determine which is suitable when selecting the right one for your needs. Functionality includes protection against moisture, oxygen, light and microorganisms; this is referred to as barrier properties. For example, paper is a huge part of flexible packaging but there are disadvantages to it such as poor barrier to air and moisture. One of the ways this is addressed is by treating paper with wax. This increases its barrier capability and also makes it heat-sealable. Plastic films, like cling wrap, are another example. Unlike glass and cans, plastic films have a wide variation of barrier properties. Therefore, the food business operator must specify the degree of protection based on the intended use and nature of the food.

The barrier property of packaging material can be measured in Water Vapour Transmission Rate (WVTR) and the Oxygen Transmission Rate (OTR). As the names implies, these rates measure how much water vapour or oxygen is able to pass through the packaging material for a specified length of time. More permeable materials have a higher reading; it is therefore important for food business operator to know this when deciding which packaging material to use.

To recap, the characteristics of food, storage conditions and functionality must be used to determine which packaging material to choose.