Chlorine concentration in NEW was found to be proportional to
chlorinated salt concentration used as electrolyte. In particular, 1 g/
L of NaCl developed about 80 mg/L of free chlorine during 30 min of
electrolysis; this concentration didn't increase during the remain-
ing electrolysis period. The electrolysis of tap water with 15 g/L of
KCl showed an increasing concentration of active clorine propor-
tional to the electrolysis period, reaching 4000 mg/L of free chlorine
after 2 h. Chlorine concentration found in electrolyzed water pro-
duced by NaHCO3 solution was not detected in line with the low
concentration found by other authors (Fallanaj et al., 2013). The
measurement of free chlorine concentration of tap water used for
dissolving inorganic salts, was always found to be lower than 1 mg/
L, so its contribute to antimicrobial activity of NEW was considered
negligible.
Since occurrence of organic matter reduces the concentration of
free chlorine and consequently its antibacterial effect, as already
demonstrated for electrolyzed water against Escherichia coli
O157:H7 in process water (Lopez-G
alvez et al., 2012), we evaluated
the loss of free chlorine in NEW in the presence of fresh cut vege-
tables. Kinetics of consumption of chlorine in NEW (Fig. 1) showed
a linear reduction in free chlorine about of 2% after 14 min. Since a
loss of chlorine equal to 5 mg/L was recorded after 5 min of contact
between NEW and fresh cut vegetables, contact time used in the
following assays didn't exceed 5 min.