Plastic packaging has become one of the most debated topics in modern food systems.
Consumers are increasingly aware of plastic waste and environmental impact, and that awareness has led many people to assume that plastic packaging is automatically the worst option.
But the reality is more nuanced. In food packaging, the type of plastic and the purpose it serves matter enormously. Some plastics are problematic. Others are among the most stable, efficient and widely studied materials used to protect food.
One of those materials is high density polyethylene, commonly known as HDPE.
Understanding how and why it is used helps clarify why many food producers continue to rely on it.
Not All Plastics Are the Same
The word “plastic” often gets used as a blanket category, but there are many different polymer types used in food packaging.
Some of the most common include:
• PET (polyethylene terephthalate)
• PVC (polyvinyl chloride)
• LDPE (low density polyethylene)
• PP (polypropylene)
• HDPE (high density polyethylene)
Each material has different properties relating to permeability, chemical stability, durability and recyclability.
HDPE has become one of the most widely used materials for food packaging because it is:
• chemically stable
• resistant to moisture and oxygen
• lightweight and durable
• widely recyclable in Australia
• approved for food contact by major regulatory agencies
For oils in particular, HDPE offers strong protection against light and oxygen exposure while remaining robust during transport and storage.
Why Glass Is Not Automatically the Greener Option
Glass is often perceived as the environmentally superior packaging material. It feels natural and permanent, which gives it a strong sustainability image.
However, lifecycle analyses consistently show that glass has a significantly higher production and transport footprint than lightweight plastics.
Manufacturing glass requires very high temperatures, often above 1500 degrees Celsius, to melt raw materials such as silica sand, soda ash and limestone. This process consumes large amounts of energy.
Studies comparing packaging materials have found that glass containers can produce substantially higher greenhouse gas emissions per unit of packaged product compared with lightweight plastics.
Research published by the International Journal of Life Cycle Assessment and data compiled by organisations such as WRAP (Waste and Resources Action Programme) show that the carbon footprint of glass packaging is often several times higher than that of equivalent plastic packaging, largely due to energy intensive production and heavier transport weight.
Because glass is heavier, it also increases fuel use during distribution.
For products shipped long distances, packaging weight becomes a significant contributor to overall environmental impact.
Why HDPE Works Well for Food Oils
For products such as cooking oils, packaging must balance several requirements:
• food safety
• oxygen protection
• durability during transport
• reasonable environmental footprint
HDPE performs well across all of these categories.
It does not require plasticisers like those found in some other plastics. It is chemically resistant to oils and fats. And it maintains structural stability across a wide temperature range.
Because it is lightweight, HDPE also reduces the emissions associated with shipping compared with heavier packaging formats.
For oils, where light exposure and oxidation can degrade flavour and quality, opaque HDPE containers can also provide practical protection.
Where Plastic Packaging Often Makes Less Sense
While some plastics serve clear functional roles, other uses are increasingly questioned.
Fresh produce is a good example.
Items such as:
• bananas
• onions
• potatoes
• citrus fruits
often have natural protective skins and can be sold perfectly well without plastic wrapping.
Plastic packaging in these cases may provide convenience for retail display, but it is not always essential for food preservation.
When Plastic Can Be Detrimental to Food
Some foods actually perform worse when sealed in plastic.
Fresh leafy vegetables, herbs and certain fruits require airflow to manage moisture and respiration. When tightly sealed in plastic packaging, these foods can degrade more quickly due to trapped humidity and microbial growth.
In these situations, breathable packaging or minimal wrapping can extend shelf life better than sealed plastic.
This illustrates an important point: the suitability of packaging depends on the product.
A Practical Perspective
Plastic packaging deserves scrutiny where it is unnecessary or poorly managed. Reducing waste and improving recycling systems remains a major environmental priority.
At the same time, materials like HDPE exist because they solve real challenges in food safety, product protection and transport efficiency.
In the case of cooking oils and similar products, lightweight, chemically stable plastics often provide a practical balance between durability, safety and environmental impact.
The goal is not to eliminate all plastics. It is to use the right material for the right job.