Water quality
The quality of the water used for washing, rinsing, heating, cooling is very important. The
water used must be appropriate for drinking. These requirements must be fulfilled to
prevent accumulation of bacteria on equipment surfaces. It is also important to prevent
accumulation of lime scale and to prevent corrosion on surfaces inside the device. Water
must be clean both microbiologically and chemically.
Microbiological requirements for water
All coliform bacteria
Faecal coliform bacteria
Faecal streptococci
Spores of sulfide reducing clostridium
Microflora standard (PCA) at 22°C
Microflora standard (PCA) at 37°C
Pathogenic microorganisms
Iron oxidizing bacteria
In the case of chlorination of non-potable water residues that could affect the quality of
the product or corrosion on the installations are not allowed.
Chemical characteristics of water
• Ammonia, hydrochloric acid, sulfuric acid, hydrogen sulfide and hydrofluoric acid must
be absent from the water.
• The amount of iron can be 0.2 to 0.3 mg / l. The water must not taste of iron.
• Lead must be absent.
• Water should be free of alkaline earth metal salt. This will facilitate the cleaning and
disinfection and improve the transmission of energy and reduce plaque on surfaces.
• The content of chloride ions must be less than 50 ppm.
HARDNESS OF WATER, WATER SHOULD BE SOFT (4-8 °DH) BASE, ACID SCALE
OF WATER, PH VALUE SHOULD BE NEUTRAL PH 7 (+/- 1) WATER MUST COMPLY
WITH STANDARDS DIN 2000 AND DIN 1988.
INAPPROPRIATE WATER (INSIDE THE DEVICE) DIRECTLY AFFECTS THE LIFE
EXPECTANCY OF THE DEVICE WHICH COULD BE SHORTENED BY HALF. WATER
SHOULD BE NEUTRALIZED (WITH USE OF FILTER, SOFTENING DEVICES, ETC.) FOR
LONGER LIFE OF THE DEVICE.
Absent in 100ml
Less than 100 CFU in 1ml
Less than 100 CFU in 1ml
Absent
Absent
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