New mathematical model developed for plastic packaging

EU regulations currently set maximum limits on how much of a packaging additive can end up in foods, with the general principle that none should be in the product in the first place. A European Commission proposal made last year would impose even tougher regulation on packaging chemicals migration. Companies can be forced to pay for costly recalls if their food products are found to be over the limits. The new modelling system was developed by researchers at the Fraunhofer Institute for Process Engineering and Packaging IVV as a means of helping companies stay on the right side of the law. They are working with nine packaging companies as part of a collaborative EU-funded project called FoodMigrosure. So far the results suggest that current means of calculating additive migration may be two low. The scientists claim their method is cheaper and more accurate than existing methods of calculation. They estimate companies can save on testing costs by a factor of between a hundred and a thousand times compared to sending samples to a laboratory. ​"The cost of computer-assisted testing is much lower than for a laboratory test, and the results are far more accurate,"​ the scientists claimed. To develop the model the Fraunhofer scientists took random food samples and subjected them to chemical tests in a laboratory. The researchers based their mathematical model on investigations of genuine foods rather than food simulants. The analyses were performed by all ten of the companies involved in the project – resulting in what the scientists are saying is the world's only systematic collection of such data. Normally, for such experiments testers replace the foodstuffs with legally prescribed food simulants such as olive oil and mixtures of water with acetic acid or alcohol. ​"However, we have found that it is not usually possible to draw conclusions about solid foods on the basis of results obtained with liquid food simulants,"​ said project coordinator Roland Franz. "In many cases the contamination of the foodstuffs is higher than hitherto assumed, and that necessitates costly product recalls."​ Using their alternative method to test genuine foods, the scientists next developed various models on the basis of these data. One model shows how the additives move about in the plastic. Another shows how many of the substances migrate from the plastic packaging material into a particular food. A third model describes how the migrants disperse in the food itself, Franz said. The researchers devised a formula to summarise the models. The formula takes into account such characteristics as structure, fat content and consistency and weds the data to the type of plastic packaging material used. The model also takes into account the various additives and the average quantity of the foodstuff actually eaten by consumers. The same formula can thus be used on one occasion to calculate how many packaging additives are present in cheese, and on another occasion to do the same for meat or orange juice. Last year the European Commission proposed legislation that would define the manufacturing practices the bloc's processors would have to take in ensuring that packaging materials do not migrate into foods. All companies would be required to follow what the law defines as "good manufacturing practice" (GMP) in ensuring that packaging chemicals do not transfer to the foods. GMP would require food companies to change their production methods to prevent the possibility of packaging substances transferring to foods. The proposed requirements would apply to chemicals that might not give rise to particular health concerns but which should not be in foods. They also apply to active and intelligent materials used in packaging to extend shelf life or indicate when food is off. The proposals are partially an outcome of food safety crisis in November 2005 in which Italy's regulators discovered that a printing chemical from a Tetra Pak package was found to have migrated into a Nestlé milk product for babies. The EU last year opened a commmunity reference lab in Italy designed aas joint research centre into the safety of specific packaging chemicals, such as those used in inks or for making the material. EU legislation requires that all materials that come into contact with food comply with health standards so that safe food remains safe. The new EU reference laboratory will set standards for testing practices for food contact materials across the EU. It will also serve as a point of reference for issues relating to the enforcement of legislation on food contact materials. This will be achieved through a network of national reference laboratories set up by each member country. It will develop methods, reference substances, and training procedures to ensure consistent testing practices are done nationally to ensure the best possible implementation of EU legislation, said the science and research commissioner, Janez Potoènik.