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Food Security

J.J. Rodríguez Jerez

Grisc – Grup de Recerca en Gobernança del Risc (UAB)

Plastic packaging and food safety

Photo: Joanne Wan

Back when food was part of a 24-hour cycle, i.e. food was bought and consumed in the same day, most food was sold in bulk and the use of cans and plastic bottles for drinks was not even contemplated. This has changed with developments in the habits of consumers, who have come to spend their leisure time on activities not related to the household. This transformation in customs is reflected in changes in packaging technology so that much of what we eat and drink is sold in some sort of container.

Today, the trip to the supermarkets has to meet weekly food needs for consumers. This change, although spectacular in hindsight, has occurred in such a gradual way that we have not been aware of it. Buying meat or fish to take home in a piece of paper and cook within a few hours or even minutes seems largely impractical today.

However, using containers carries its own risks for two reasons. The first is concerned with consumer health. Packages are not simply some inert divider placed between the food and the external environment to avoid tampering or contamination. The materials used in packaging, which are a vital element to maintain quality and safety, can be transmitted to a greater or lesser extent to the actual food. The second risk is environmental, since plastics have a low recycling rate and take many years to degrade.

Plastics and the environment

With regard to environmental hazards, for years experts have identified the harmful effects of polyethylene terephthalate (PET), which have been linked with a host of problems for both food safety and the environment. PET is the basis of most plastic bottles and can be easily identified, because if the bottle contains it, will bear certain symbols.

Recently, the German Institute for Energy and Environmental Research (IFEU, in its German acronym) has presented the results of a study on the environmental problems of plastics and concluded that single-use PET plastics are actually “greener” than recyclable glass. According to this study, the reasons are clear: a reduction in the weight of the bottle by 14%, implying a smaller amount of PET; the increased use of recycled materials (25%-35%); the shortening of distances between the centers of production and distribution (38%); and reduced energy consumption (30%) and water use (36%) in the manufacturing process.

Protecting food and releasing substances

Classifications increasingly divide containers into passive or active. The first is used as a simple barrier between the food and the exterior; it provides physical protection, which will most likely prevent anyone or anything from tampering with the food. This is the case for most packaged fruit and vegetables as well as most beverages, including bottled water.

The key to preventing the migration of plastic substances into water does not pass through a redesign of the packaging material, but by improving hygienic practices Active packaging has the characteristics of passive packaging because it physically protects food, but at the same time, may transfer substances to the food in order to provide a specific characteristic. Among them are preservatives or the aroma that is released when you open the package. This type of product may alarm some customers, since it is unknown what effect the substance to be incorporated into food has on its consumption. This response is linked to fear that the additives in plastics may pose a health risk.

Against this background, the European Food Safety Authority (EFSA) requires that different products coming into contact with food are assessed by the CEF scientific committee (food contact materials, enzymes, flavorings and processing aids), in order to authorize their use. Importantly, this case is different from food additives, since the number of manufacturers of plastics and packaging materials is very low. This makes the control measures more effective.

Plastic containers and water

Drinks, of all types of alimentation, have the most prolonged contact with containers. And among these, water is the most highly consumed. The consumption of water from plastic bottles has become common practice, and more than once we might have thought that bottled water has a slightly odd taste.

This strange taste is due to migration from the plastic bottle to water. Most of the time, the responsibility does not lie with the packaging. Interestingly, the customer is usually the culprit when he or she refills an empty bottle with tap water. The advantages of plastics are that they are cheap and light, so we reuse the bottles, but often we leave them in the sun, inside a car in summer or in the refrigerator.

The solution to this situation is not to redesign the materials so that substances have no taste, but rather to improve our hygienic practices. Keep in mind that plastic bottles can not be exposed too long to direct sun light. This light has a certain amount of ultraviolet radiation, which increases the transfer of plastics into the water. Something similar occurs with excessive heat, which increases the ability to dissolve plastics. The more heat, the more water will taste odd and the more plastics that will enter in our diet.

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1 comment

Julio Ortega 06/02/2012
En Colombia se utiliza tubular plástico de sólo polietileno y otros tienen 3 capas,por ejemplo, 2 capas de polietileno y una al centro en polipropileno formando una tricapa. Normalmente un rollo de plástico tubular para agua pesa 6.6kg ¿Por qué algunos rollos sueltan sabor a plástico al agua y otros no?, adicional a la temperatura y la exposición del material plástico a la luz ultravioleta, si un rollo la fabricó mi proveedor de empaques hace 15 meses y Yo voy a usarlo después de ese tiempo, ¿ es posible que el agua envasada allí tome sabor a plástico por las migraciones del material? .

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