Hygienic properties exhibited by single-use wood and plastic packaging on the microbial stability for fish

Abstract

In the present study, wooden (pine and poplar) and plastic (high-density polyethylene -HDPE- and expanded polystyrene -EPS-) materials were evaluated to assess hygienic properties. Three types of studies were carried out: evaluation of the natural microorganisms present in the materials, antibacterial efficacy tests against Staphylococcus aureus and cross-contamination tests using boxes of different materials in contact with two distinct fish species. Results showed that different materials presented natural microbial load. HDPE and EPS did not present antibacterial properties, showing an increase in S. aureus counts of 0.7 Log CFU cm−2 and 1.2 Log CFU cm−2, respectively. In contrast, poplar wood reduced the initial bacterial numbers by 0.1 Log CFU cm−2, and pine wood was able to significantly reduce S. aureus initial bacterial load by 2.84 Log CFU cm−2 (P < 0.05), presenting the higher antibacterial activity. Through studying the cross-contamination between wooden and plastic boxes and the fish product, it was indicated that wood does not affect fish quality or safety, as microbial counts decreased after they were in contact with the fish products for seven days. Based on the results obtained, single-use wood packaging is a hygienic option and highly recommended for fish product transportation.