Foam

Foam cleaning is widely used for open plant cleaning and refers to the cleaning process where the main detergent is applied as foam. The benefits include the ease and safety of application, extended contact time between detergent and soil and overall reduced labour and time for cleaning.

Alkaline based foams are the most common used for cleaning in the food industry. They will range from approximately pH8 to pH12 (in use) and are effective on most types of soil encountered including poultry, red meat, fish and vegetable.
Some alkaline foams are inhibited and may be safe to use on soft metal such as aluminium, tin, brass etc. Uninhibited alkaline foams may cause some corrosion to soft metals. Therefore when selecting the type of foam to be used, consideration should be given not only to the soil to be removed but also the materials of construction that the foam detergent will come into contact with.

Caustic Foams
These types of foam detergents will usually be used to remove heavy carbon, grease and fat deposits found in ovens, fat fryers and cookers. They will range from pH12 to pH14, are very aggressive and should never be used on soft metals such as aluminium, tin, brass, copper and zinc.

Chlorinated Foams
Chlorinated foams are alkaline based with a chlorine “donor”. They are usually very powerful detergents effective on removing fats, heavy protein deposits and fruit or vegetable staining. They are utilised in primary processing sectors such as red meat, poultry, fish, vegetables and fruit. The introduction of hypochlorite in the formulation is to assist with protein removal rather than acting as a biocide.

Acid Foams
Acid based foams are used for the removal of mineral scale and protein build up. They will usually be used in primary processing areas such as poultry plants, abattoirs, salad, vegetables and fruit or in hard water areas (usually more than 200ppm). They will range from pH1 to pH4, are aggressive and care should be taken on soft metals such as aluminium, tin, brass, copper and zinc.

Detergent/Disinfectant Foams
QAC (Quaternary Ammonium Compound) foams are used mainly for light to medium cleaning tasks such as break cleaning and product changeovers. They can be used for main cleaning duties but in this situation should be followed by a disinfectant (a two stage clean).

Neutral Foams
Neutral foam detergents are by description approximately pH7. They are usually used where soft metals are present or to reduce the hazards of cleaning and therefore reduce the need for Personal Protective Equipment.

Gels
Gels are applied in the same manner as foams but may require different lances or nozzles to ensure an effective coverage. They are available in the same range of chemical compositions as foam detergents. The main issue with gels is that when applied it is very difficult to see them as they have a clear appearance. To assist visibility gels are often aerated (mousse).