The Variety of Materials for Ready Meal Primary Packaging Container
Share this post
Tablet of Content
Primary packaging containers refer to the packaging that has direct contact with the product itself and for the purpose to protect and preserve the finished product against exterior contamination including ambient gas, moisture, bacteria, etc. [1]
In the food industry, the versatile packaging design for ready meal packaging containers ranges from the most commonly used trays to tubs and pots, and sometimes cups. The primary packaging container for ready meals plays a crucial role not only in protecting the food but also in its presentation, convenience, and environmental impact. By mention the environmental concern we are to address the impact of packaging materials used for forming ready meal containers, and the recycling of which may have, to some extent, considerable impact to sustainability.
In the presenting industrial insight, we will be investigating into the various kinds of materials used for ready meal packaging formation as well as their characteristics and properties.
Packaging Containers for Ready Meals are Made by Various Materials
Ready meals see the essentialness of preservation and contamination-proof now that they are prepared food to be kept in the container for a period of time before they are consumed by the consumer. Common materials employed in ready meal packaging include plastics, aluminium, paper, and increasingly, biodegradable materials. Each of these materials comes with its unique set of properties that can significantly influence a product’s shelf life, convenience, and sustainability.
Plastics (Polymers)
Polymers are indeed considered plastics and are frequently used for forming the primary packaging of ready meals. Polymers, from the chemical perspective, are large molecules composed of repeating structural units, and when these polymers are synthetic and have properties that make them light, durable, and flexible, they are commonly referred to as plastics. The term that refers to this principle is called Polymerization. [2]
Polymers/plastics are favoured in the food packaging industry for several reasons, including their ability to be moulded into various shapes, for which they are commonly used for thermoforming processes. Featuring further, apart from this advantage, are their chemical resistance, and barrier properties against moisture, gases, and contaminants, which are key external factors to be mitigated in order to extend the food’s shelf life.
- Polyethylene Terephthalate (PET): PET preformed packaging containers like trays are typical options of packaging container for ready meal, especially those made as microwavable meals. The reasons behind such preferences are that PET has a melting point of 260 °C, which is higher compared to many other plastics, making it capable of withstanding the temperatures typically encountered during microwave cooking without melting or deforming.
- Polypropylene (PP): PP is another packaging material preferred for its high melting point of up to 160 °C, making it suitable for containers that need to withstand high temperatures during microwave cooking or hot filling processes. PP is more versatile and flexible now that they can be made into both rigid and flexible forms.
- Polystyrene (PS): PS is used for its versatility and cost-effectiveness. It can be found in various forms, including foam trays and clear containers. However, it’s not as heat-resistant as PET or PP, limiting its use to certain types of ready meals. PS recycling is less common than PET and PP, raising environmental concerns.
- Polyethylene (PE): PE is commonly used in packaging films and bags. Its excellent flexibility and barrier properties make it suitable for sealing over trays or as a part of multi-layer structures to improve the overall barrier performance of a package. PE is recyclable but often requires specific facilities.
- Biodegradable Polymers: These are emerging as alternatives to traditional plastics, made from renewable resources like corn starch (PLA or polylactic acid) or biodegradable petrochemicals. They offer a promising route towards reducing the environmental impact of packaging, although their performance and cost-efficiency are still under development.
- Ethylene Vinyl Alcohol (EVOH): Ethylene Vinyl Alcohol (EVOH) is a copolymer of ethylene and vinyl alcohol, known for its exceptional barrier properties against gases such as oxygen, carbon dioxide, and nitrogen. EVOH is frequently used in combination with other materials through co-extrusion or lamination processes.
Aluminium-Based Packaging Container
Aluminium-based packaging, including foil and aluminium trays, is another popular option for ready meal packaging, including those intended for oven or microwave heating (with appropriate microwave-safe designs). Aluminium offers several distinctive advantages and some limitations when used as primary packaging for ready meals, due to the reasons of the latter they are no longer the prioritized option for ready meal packaging container.
More expensive, less suitable for microwaving
The most typical disadvantage is that standard aluminium packaging is not suitable for microwave use due to the risk of sparking (arcing) and uneven heating. However, there are specific aluminium packaging designs that are made to be microwave-safe by incorporating features that prevent arcing and allow microwaves to penetrate the food. Regardless of such an improvement, aluminium can still be more expensive compared to polymer packaging, impacting the overall cost-effectiveness for manufacturers and possibly the retail price for consumers.
Excellent Thermal Conductivity
Aluminium’s superior thermal conductivity ensures even heating of the food, which is particularly beneficial for oven-based ready meals. In microwaves, special microwave-safe aluminum packaging is designed to prevent arcing and ensure even heating.
Paper-Based Packaging Container
Both consumers’ awareness for sustainability and the regulation requirements are acting as the driving force to ready meal packaging turning to more eco-friendly options including paper-based materials and cardboard.
Paper-based packaging is more sustainable
Paper and cardboard are made from renewable resources, primarily wood pulp, which makes them highly sustainable, and whose production also tends to have a lower carbon footprint compared to many plastics and metals. Paper and cardboard have The recycling of cardboard and paper has well-established processes and high recycling rates in many countries, further enhancing their environmental appeal.
Compromised reliability in strength and temperature resistance
Sustainability has a cost. In the case of paper-based packaging container, the packaging is more vulnerable to moisture or fats, against which paper materials can lose strength and integrity. A necessary method to avoid this downside can be additional treatments and coatings, yet they engage further costs and can compromise their convenience of recycling. Paper-based packaging generally has lower resistance to high temperatures, limiting its suitability for oven-ready or microwavable meals without special treatments.
Bibliography
[1] Primary, Secondary, and Tertiary Packaging: What is the Difference? Published on 9 August 2019, Cartier Packaging Optimized, https://www.emballagecartier.com/en/article/primary-secondary-and-tertiary-packaging-whats-the-difference/
[2] From Classical to Advanced Use of Polymers in Food and Beverage Applications, Polymers (Basel). 2022 Nov; 14(22): 4954. Published online 2022 Nov 16, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9699061
