While reductions in microbial
population were observed with increasing treatment time,
a maximum decrease of approximately 1 log cfu/ml was achieved
after 8 s for both E. coli and L. innocua. No significant differences
were found between any of the treated samples inoculated with
E. coli, irrespective of exposure times used, however, the samples
were significantly different from the untreated control (p < 0.01). In
contrast, significant reductions in L. innocua counts were found in
orange juice treated for 8 s compared to the juice treated for 0, 2 or
4 s (p< 0.001). The data in relation to storage for up to 48 h at 4 C
did not confirm any sign of post-treatment microbial recovery.