PMC

Schematic of reactors MFC (a); CW (b); CW-MFC (c): (1) Modified carbon felt the cathode. (2) Activated carbon. (3) Glass wool. (4) Gravel. (5) Carbon brush anode. (6) Gravel. (7) Glass wool.

Photographs of MgF₂ films on soda-lime glass (left) and borosilicate glass (right) substrates (width 10 cm) after different numbers of Crockmeter testing cycles with felt and steel wool as abrasive medium. Reproduced with permission from []. Copyright The Royal Society of Chemistry, 2012.

Microbial cell count in filtrates. Samples consisting of A) ground beef, B) ground pork, C) ground turkey, and D) spinach were inoculated to attain an initial concentration of ~10⁶ CFU/mL of the following bacteria: E. coli (blue bars), L. monocytogenes (red bars), and S. enterica (green bars). Strains utilized possessed antibiotic resistance markers to allow enumeration of the specific pathogens on agar plates containing antibiotics. The number of colony forming units (CFU) per mL of sample is shown for the three pathogen after each of the four treatments (glass wool, 50 µm filter, graphite felt, and continuous flow centrifugation (CFC)). Because samples were processed via the Stomacher prior to the above listed treatments, the stomached samples represent the initial reference point (the inoculum). In addition, for inclusiveness, the CFU/mL is listed for both the liquid retentate and the effluent of the CFC.

Particle size analysis. (a) Particle size distribution was determined with dynamic light scattering. Sample matrices consisted of ground beef, ground pork, ground turkey and spinach as indicated on the right axis. All samples were initially processed via a filtered stomacher bag (blue line) to mix the sample and remove extremely large particulates and is considered the pre-filtration reference point for these experiments. Samples were then subjected to the stated separation methods and the particle size distribution is shown post-processing via glass wool – red line; 50 μm filter – green line; graphite felt – purple line; and continuous flow centrifugation (CFC) – black line. (b) Average values collected for treated samples corresponding to the size points in the distribution patterns where 10, 50, or 90% of the total material volume was either equal to or smaller than the listed size (Dv 10, Dv 50, or Dv 90 respectively) are grouped by food matrix. Student’s t-tests were utilized to compare the effect of treatments on the Dv 10, Dv 50 and Dv 90 calculated from particle size distribution data. Statistically different values (p < 0.05) are indicated by the connecting letters report. The letters are organized within groups from A-E with the alphabetical progression being associated with lower means.