Silicon Migration from High‐barrier Coated Multilayer Polymeric Films to Selected Food Simulants after Microwave Processing Treatments

Abstract

The use of microwave (MW) technology for in‐package food sterilization and pasteurization has the potential for widespread use in the food industry. Because the use of MW technology requires that food be processed inside its packaging, the interaction between food and its packaging during processing must be studied to ensure package integrity as well as consumer safety. In this study, two commercially available multilayer films developed for retort sterilization were evaluated for their suitability to MW processing. Film A was composed of oriented nylon//coated polyethylene terephthalate//cast polypropylene (CPP); film B consisted of oriented nylon//coated nylon//CPP with overall oxygen transmission rates <0.2 cc/m2. day. Silicon (Si) was a major component in the coated polyethylene terephthalate layer and food‐contact CPP layer. This study evaluated the influence of MW processing on Si migration from films into selected food‐simulating liquids (FSLs; water and 3% acetic acid) using inductively coupled plasma‐mass spectroscopy, as compared with conventional thermal processing. This study also assessed migration of Si into FSL in terms of process temperature (70–123 °C) and time (18–34 min). A Fourier transform infrared spectrometer was used to evaluate the stability of the silicon–oxygen (Si–O) bonds in the metal‐oxide coated and food‐contact layer of the packaging film. Overall, there were no significant differences (p > 0.05) between the level of Si migration from films to FSL and the stability of Si–O–Si bonds during MW processing as compared with the conventional thermal processing. However, we found that the final processing temperature and time had a significant (p < 0.05) impact on Si migration into the FSL. Copyright © 2013 John Wiley & Sons, Ltd.