The chloride, nitrate, phosphate, sulphate and oxalate
contents of water samples obtained during the processing
of frozen and canned spinach were compared (Table 1).
In fact, the levels of chloride in the water used during the
processing of frozen and canned spinach varied from 190
to 345 mg/kg. The mains water analysed during processing
had a concentration of about 160 mg/kg, which
agreed with the levels provided by the regional Health
Authorities and fell below the limits established by the
WHO to avoid off-tastes and piping corrosion (WHO
1993). It must not be forgotten that the water entering
the washing room is chlorinated for hygiene reasons. The
water used as filling medium was excessively high in
chorines as NaCl was added during the canning step