Statistical analysis was carried out using Statgraphics Centurion
XVI.I (Statpoint Technologies, Warrenton, VA). A one-way ANOVA was
conducted to rule out the effect of the concentration of nitrate/nitrite
on each single parameter (aw, pH and microbial counts) analyzed
on each sampling day. Statistical significance was identified at 95%
confidence level. Duncan's multiple range test was used for mean
comparisons.