Microplastics in food and drink: overview
- Microplastics widely contaminate food products, including packaged baby foods
- Contamination originates from packaging materials, processing conditions and environmental sources
- Manufacturers can reduce risk by replacing plastics and improving ingredient sourcing
- Filtration, monitoring and AI detection help identify and remove microplastics
- Consumer misuse, such as microwaving plastics, increases microplastic contamination risks
Microplastics were recently found in Nestlé Gerber and Danone baby foods, sparking renewed controversy for the two companies.
The discovery, by the organisation Greenpeace, identified microplastic particles in every analysed sample of Nestlé’s Gerber and Danone’s Happy Baby Organics products, which are sold in plastic squeeze pouches.
Nestlé and Danone are not alone in seeing this contamination in their products. Microplastics are a problem across the food industry.
It is important that food companies are aware of this issue. Consumption of microplastics has been linked to negative health impacts including abdominal pain, nausea and vomiting.
How can manufacturers keep them out of food? There are a range of approaches, both in removing microplastics from food and drink, and preventing contamination in the first place.
1. Replace synthetic coatings
In order to avoid microplastic contamination, manufacturers should replace synthetic coatings with alternatives, says Claire Sand, owner of the company Packaging Technology and Research.
While PE or PET laminations on paperboard are often the source of microplastic contamination, alternatives like aqueous polymer dispersion coatings can provide the same moisture, grease and liquid resistance without such a high risk.
Biodegradable and bio-based polymers have been explored as alternative materials due to their lower propensity to generate microplastics.
2. Sourcing ingredients with lower microplastic contamination
Microplastics often enter a product through the ingredients used to create it, far before the finished product has come into existence. Such sources include water, seafood and agricultural products exposed to contaminated soils or irrigation water.
To avoid this, says Packaging Technology and Research’s Sand, manufacturers should work hard to source ingredients that are not contaminated with microplastics.
“Auditing and selecting ingredient sources with lower environmental microplastic burdens reduces the load that enters production before packaging or processing even begins.”
3. Avoid plastic contact during high-risk processing conditions
The fragmentation and migration of plastic particles can increase with acidity, high temperatures and fat contact. Contact points in the production process that pose a particular risk, such as heat processing and contact with acidic foods and high-fat products, should therefore be reduced.
Once such high-risk contact points of production have been identified, explains Sand, manufacturers can substitute non-polymer alternatives for these points.
By doing this, “companies can reduce microplastic generation even if some plastic packaging is retained elsewhere in the system”.
4. Filtration
Water filtration during production can stop microplastics from entering a food product.
“Installing filtration systems – such as ultrafiltration or reverse osmosis – at points where water contacts food during production captures microplastic particles before they reach the product," says Sand.
For liquid products such as oils, beverages and dairy, inline filtration systems can also physically capture microplastics from the product.
Membrane filtration, depth filtration and centrifugal separation can all be applied at different stages in the production process to remove microplastics from these products.
5. Advanced monitoring
Monitoring for the presence of microplastics in packaging can help prevent contamination.
Advances in spectroscopic and thermal analysis methods have enhanced the accuracy of microplastic detection, helping manufacturers to find microplastics in packaging. Spectroscopy is the use of the interaction between light and matter as an analytical tool by measuring the emission, absorption or scattering of electromagnetic radiation.
AI has been used to detect microplastics and can reduce errors in methods such as advanced spectroscopy.
6. Ensure consumers do not misuse packaging
Microplastic generation often occurs as the result of consumers misusing products, according to Sand.
For example, microwaving food in non-approved plastic containers can make microplastic contamination more likely, as can storing food beyond the packaging material’s intended shelf-life.
It is essential to communicate to consumers how to use materials safely and to avoid the generation of microplastics.
What this means for industry
Microplastics are a persistent issue within the food sector. Contamination is widespread and not always easy to detect.
With the risk it poses to consumer health, industry has an obligation to strive to minimise it.
While these methods will not push the risk of microplastic generation to zero, they will help reduce it.
