Wood is commonly used in contact with foodstuffs, for example for packaging fruits or vegetables. Most common species used are beech, pine, spruce and poplar. Wood is often considered as being less safe than plastic because it is less easy to clean whereas several studies have demonstrated that microorganisms cannot survive easily on wood (Milling et al., 2005; Revol-Junelles et al., 2005). National recommendations for packaging fruits feel the necessity for clean materials, whether it be wood or plastic (Lurol et al., 2007). The analysis of microbial contamination is standardized only for paper and cardboard materials (Anonymous, 1998). No standard exists yet for wood packaging. A comparative analysis was managed to remove microorganisms from wooden surfaces used in the food industry. A grinding technique was developed on poplar (Ismaïl et al., 2014). On the basis of this method, the transfer of microorganisms from wood to foodstuffs was analysed. The model “poplar packaging/apple” was chosen. The two microorganisms Escherichia coli and Penicillium expansum were considered, as they are a well-known risk for apples. In a first step of this work, the survival rate of the microorganisms on poplar crates was assessed, after 1h, 1 week and 3 weeks. The wood was artificially inoculated by different concentrations of the two microorganisms. In a second step, the transfer rate of microorganisms from poplar to apple was quantified, after 1h and 1 week of contact, still using several inoculum concentrations. Finally, a model was finalized using our results to describe a transfer threshold for both microorganisms from wooden packaging to apples. Analysis on wounded apples was also carried out.

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