In an article published on February 10, 2020, in the peer-reviewed journal Molecules, Magdalena Wrona and Cristina Nerin from the Department of Analytical Chemistry, Aragon Institute of Engineering Research I3A, University of Zaragoza, Spain, provide a review of “the development and application of new analytical methods for detection of possible food contaminants from the packaging origin on the quality and safety of fresh food.”
The authors offer a thorough discussion of analytical methods available for the analysis of organic volatile compounds, organic non-volatile compounds, and inorganic nanoparticles originating from food contact materials (FCMs). The analysis of non-intentionally added substances (NIAS) is illustrated with several examples from real samples. Interestingly, incorporation of antioxidants into polymer packaging “not only protects food products but also can lower or totally prevent the migration of some compounds,” such as oligomers from polylactic acid (PLA) packaging, the authors note. The study of odorous volatile compounds that can influence taste and smell of stored food appears “especially important in the case of new FCMs such as biopolymers.” Detection of nanoparticles requires a special set of analytical techniques.
The authors emphasize that, when creating a new active packaging article, “not only the release of active agents, but also the potential impurities and compounds used to incorporate the active substances, should be under control.” Thus, “all volatile and non-volatile compounds migrating to food simulants” should be screened. Further, for some essential oils (EOs) which are used as antimicrobial substances in active packaging applications, it has been shown that “micro-organisms from food can interact with EOs from antimicrobial packaging and produce new substances.” For example, the Aspergillus flavus strain was shown to form methyl eugenol, styrene, and linalool oxide from cinnamon essential oil. Therefore, analysis of migration from antimicrobial packaging should take into account the new substances potentially coming from biotransformation, the authors point out. They also highlight the importance of “the application of migration assays from the new materials to real food . . . and not only to food simulants.”
The authors conclude that “comprehensive analysis of migration samples requires different analytical techniques as well as a wide knowledge about the types of technologies and materials applied in the packaging industry, the application of novel scientific solutions such as active packaging, and the type of potential migrants.” NIAS are “the most difficult group of compounds to identify in migration samples,” demanding “the collaboration of chemical and plastic industries with the researchers working on plastics safety, in order to provide the necessary information about the chemicals’ and polymers’ impurities, additives, and possible side-reactions.” The development of new analytical methods for nontarget analysis is also expected to further facilitate the task of determining and quantifying unknown migrants.
Wrona and C. Nerin (2020). “Analytical approaches for analysis of safety of modern food packaging: A review.” Molecules 25: 752.
Becerril, R., et al. (2019). “Metabolites identified as interaction products between EOs from food packaging and selected microorganisms.” LWT 116: 108518.