Active graphene based food packaging systems for a modern society (GRAFOOD)

Introduction: The shelf life extension of food products represents today one of the biggest challenges in the food industry [1]. The GRAFOOD project aims to solve this challenge by developing a pilot-scale prototype of active food packaging based on paper and polylactic acid (PLA) film modified by graphene oxide activated by probiotics and by nano-Ag-TiO2, respectively [2]. Methods: The first step of the project studied the organoleptic, chemical and microbiological evolution of short shelf life cheeses and chicken breast stored at 4°C. Samples were packed in commercially available food packaging from Italy, Spain, Romania and Slovenia during a period of 14 days. Chemicals tests were done monitoring the evolution of shelf life marker concentrations by GC-MS and HPLC-DAD. Results: A preliminary study confirmed that Ricotta cheese was the most adapted about the cheeses taken in consideration allowing a more pronounced increment of free fatty acids in a shorter time. Once chosen, all the tests were performed comparing the different food packagings. The GC-MS analyses showed an increasing of markers from the day 0 to the day 3 followed by slight variations along the remaining days. Microbiological tests showed a growth of mesophiles, psychrophiles, coliforms, mold and yeasts amounts over the time. For the chemical analyses of chicken meat, a HPLC-DAD method was developed and validated to quantify biogenic amines as shelf life markers in chicken breast samples. Their increment was observed over the time in all the type of packaging. This increase was also assiociated to an increment of chicken pH and a microbiological growth during the time. Conclusions: This step of the GRAFOOD project allowed to observe chemical, organoleptic and microbiological changes in cheese and meat samples packed in commercial packagings. Each packaging presented special features on packed samples although none of them showed a marked prolongation of their shelf life. The obtained results will serve to evaluate the efficiency of future active packagings shortly developed. References 1. Akkerman, R., Farahani, P. & Grunow, M., OR Spectrum, 863–904 32: 863. (2010). 2. M-ERA.NET Call 2016: Funded projects.