60
3 The Durable Management of Chemicals in the Food Industry …
The same chemical may have different usefulness depending on the chosen dilution; it is therefore important to read the technical sheet. Moreover, chemical properties of water (e.g., its alkalinity or hardness) can significantly impact on the chemical
effectiveness of a product.
3.11.2.2 Mechanical Action
The mechanical action on a surface can be expressed in different ways. Manual
equipment (e.g., brushes and mops) is used to scrub surfaces on which the use of
a machine is not applicable. Electromechanical equipment such as the low-speed
polisher or the car washer generates greater pressure and friction.
During cleaning operations, the mechanical action must be modulated in order to
avoid surface alterations. Actually, and with specific relation to food-related machines
and equipment, the main problem is the damage, e.g., partial demolition of Tefloncoated surfaces for melting machines (cheese-making industries); fractures of plastic
molds (various equipment and food-related productions) after repeated cleaning with
mechanical tools; etc.
3.11.2.3 Contact Time
Contact time defines the required time of presence of a chemical on a surface for
optimal efficiency. During cleaning and disinfection operations, the respect of contact
times ensures the desired result of the chemical action.
On the other side, failure to respect the contact time can prevent the chemical from
acting properly: Little or no effect if the product is not left long enough or possibility
of damaging the surface if the product is left too long time.
Some chemicals remain ‘effective’ once dried (e.g., quaternary ammonium salts),
making it easier to reach their contact time. On the other hand, other products
must remain in aqueous solution to reach the necessary contact time for their full
effectiveness (e.g., chlorine).
3.11.2.4 Temperature
Thermal action influences the qualitative result of cleaning activities. The thermal
action can be generated by the temperature of the solution or by a mechanical action
such as the friction of a pad on a ground surface. Some chemicals are effective within
a certain temperature range.
3 The Durable Management of Chemicals in the Food Industry …
The same chemical may have different usefulness depending on the chosen dilution; it is therefore important to read the technical sheet. Moreover, chemical properties of water (e.g., its alkalinity or hardness) can significantly impact on the chemical
effectiveness of a product.
3.11.2.2 Mechanical Action
The mechanical action on a surface can be expressed in different ways. Manual
equipment (e.g., brushes and mops) is used to scrub surfaces on which the use of
a machine is not applicable. Electromechanical equipment such as the low-speed
polisher or the car washer generates greater pressure and friction.
During cleaning operations, the mechanical action must be modulated in order to
avoid surface alterations. Actually, and with specific relation to food-related machines
and equipment, the main problem is the damage, e.g., partial demolition of Tefloncoated surfaces for melting machines (cheese-making industries); fractures of plastic
molds (various equipment and food-related productions) after repeated cleaning with
mechanical tools; etc.
3.11.2.3 Contact Time
Contact time defines the required time of presence of a chemical on a surface for
optimal efficiency. During cleaning and disinfection operations, the respect of contact
times ensures the desired result of the chemical action.
On the other side, failure to respect the contact time can prevent the chemical from
acting properly: Little or no effect if the product is not left long enough or possibility
of damaging the surface if the product is left too long time.
Some chemicals remain ‘effective’ once dried (e.g., quaternary ammonium salts),
making it easier to reach their contact time. On the other hand, other products
must remain in aqueous solution to reach the necessary contact time for their full
effectiveness (e.g., chlorine).
3.11.2.4 Temperature
Thermal action influences the qualitative result of cleaning activities. The thermal
action can be generated by the temperature of the solution or by a mechanical action
such as the friction of a pad on a ground surface. Some chemicals are effective within
a certain temperature range.