Disinfection
It should be used on those surfaces where microorganisms are found and will affect ready to eat or high risk food. Disinfection should be use on:
- Food contact surfaces
- Hand contact surfaces
- Cleaning materials and equipment
- Fruit and vegetables to be consumed raw
- Hand disinfection
Since microorganisms are mostly found in food, the disinfection of non food contact surfaces such as floors and walls is rarely necessary. However, surfaces that do not come in contact with food but with food handlers, there is a need to disinfect, to prevent the build-up of microorganism.
Cleaning procedure
Every F&B industry, there is at least one single sink for dishwashing. It is important to use water as hot as possible, just below 60 degree Celsius. Remember to replace the water frequently as it becomes cool or greasy. Especially in a steak house, the deep fry fries will cause the plates to be greasy. Measuring equipment must be cleaned frequently.
Soak cleaning is used for small items to extend contact time with the detergent. It is beneficial on heavy or tenuously soiled items. Highly carbonized trays, such as pizza trays can be cleaned successfully in this manner. Detergents are often highly alkaline and may need to be formulated to be suitable for use with aluminium.
There are six stages in a cleaning manual
1. Pre clean: sweeping, wiping or scraping off loose debris, pre-rinsing/pre-soaking.
2. Main clean: Applying detergent and loosening of the main body of dirt.
3. Intermediate rinse: Removal of loosened dirt and detergent residues.
4. Disinfection: Destruction of remaining microorganisms
5. Final rinse: removal of disinfectant residues.
6. Drying: Removal of final rinse water and storing to prevent contamination.
When might a pre-clean not be strictly necessary?
When items are not heavily soiled, a pre-clean may not necessary. For example, chef’s whites may not need soaking if they are not stained or badly soiled. Plates may not always need to be scraped clean of waste. However, pre-cleaning should be allowed for, as there is always a possibility that it may be needed.
Why is drying necessary?
Drying is important because wet objects tend to attract bacteria. Dust also comes in contact with them and water act as a medium for bacterial transfer and growth. Drying may be by evaporation or by a cloth. Cloth drying is quick and efficient. It lower the chances of re-contamination but the cloth itself must be very clean. Disposable paper towels can also be used for cleaning, however extra precautions must be taken to prevent torn of pieces paper become part of the physical contamination.
Type of water: Water hardness is the amount of dissolved minerals (calcium, iron, magnesium) in the water. Cleaning in hard water can be more difficult because the minerals present can reduce the effectiveness of some detergents. Hard water may cause a scale or lime deposit and for on equipment when boiling or evaporation occurs. Use detergents containing “builders” that tie up the minerals can help prevention of lime build up, as well as keep the hardness from affecting detergents.
The cleaning procedure removes dirt using water and a detergent. Most dirt and soiled consist of food particles and dust which has become to a surface by grease. Hot water will soften and remove the dirt. Water alone will only remove greasy areas with dirt if the temperature is about 80 degree Celsius. However, this is too hot for handling and is not very efficient. Soap or detergents are used to remove greasy materials. For example, sanitizers and dishwashing liquid are used for cleaning kitchen areas and equipment, while soap is used for hand washing. It is always best to used hot water when cleaning, but temperature of 50 to 60 degree Celsius will be adequate and is not too hot to handle. Disinfection can be omitted on non critical surfaces. Drying can be natural such as air drying or physical, using disposable paper towels, hot air or a clean dry cloth.
Preliminary and post-cleaning actions
In the case of dangerous or electrical equipment, preliminary safety procedures and final safety checks are required. Several types of equipment will be partial or complete dismantling to ensure effective cleaning.
Double-sink washing
This procedure is recommended for washing up in retail outlets selling high risk foods. As for steak house, our main food is beef, a high risk food. Beef is raw foods that can cause cross contamination easily if not handle properly. It also contains high level of water activity and is high in protein content. Hence, they are potentially hazardous foods that are able to support the rapid and progressive growth of microorganisms than others. Thermal disinfection is usually more effective if double sinks are used. However, the evaporation of water often results in poor visibility and condensation, leading to mould growth on ceilings and walls. Moreover, hot water at 82 degree Celsius may pose an unacceptable health and safety risk. The full six stages that should always followed:
1. Remove any heavy or loose soil by scraping and rinsing in cold water
2. Place articles in the first sink in detergent solution at 53 to 55 degree Celsius, scrub with a suitable brush and wipe with a clean cloth to lossen dirt residues
3. Re-immerse in the first sink to wash off loosened dirt
4. Place articles in the second sink to rinse off chemical residues
5. Leave for sufficient time at high enough temperature to ensure rapid air drying.
6. Baskets for disinfecting purposes should be maintained in good condition and inspected regularly. They should be loaded so that all surfaces of crockery and equipment are fully exposed to the rinse water. Hollow items such as cups should be place on their side
7. Remove articles; allow draining and evaporating dry on a clean, disinfected surface.
The order of washing-up should be planned so that glasses and lightly soiled articles are cleaned first. For safety reasons, glasses should be washed one at a time. Some articles may need pre-soaking and treatment with abrasive pads. Disposable paper toweling placed on the draining surface helps absorb water and reduces noise. Clean pans and cups should be inverted and protected from contamination during storage. Dishcloths should be semi-disposable or discarded daily. Cloth should never left wet or soaked in disinfectant overnight as this can result in a build-up of resistant bacteria.
Mechanical dishwashing
1. Remove excess food into suitable waste bins, if necessary pre-soak or spray
2. Pack articles in a neat, orderly fashion so that items do not overlap
3. Articles pass through the wash cycle of hot detergent solution (49 to 60 degree Celsius)
4. Articles are rinsed at 82 to 88 degree Celsius, with the injection of rinse aid
5. The dishwashing cycles are complete and disinfected articles may be accessed
6. Allow cleaned items to drain and evaporate dry before storage(Inverted)
To ensure that the best results are obtained, it is important that machines are serviced regularly, operated in accordance with manufacturers’ instructions and that:
1. Utensils are washed as soon as possible after becoming soiled.
2. The correct detergent for the level of water hardness is used.
3. The detergent dosing equipment is working properly and detergent rinse levels are properly adjusted
4. Sprayer art jets are clean from obstruction and strainers are in place. Both should be cleaned daily
5. Track speed, where appropriate, is properly adjusted to give the contact time required for the detergent used.
Cleaning a work surface
For stainless steel and similar surfaces:
1. Remove loose debris with a clean, loosely folded cloth(pre-clean)
2. Wash with hot detergent solution and a clean cloth or brush(Main clean)
3. Rinse with hot water and a clean cloth(intermediate rinse)
4. Apply a suitable disinfectant and allow sufficient contact time
5. Rinse off with fresh water and disposable paper(final rinse)
6. Allow to evaporate dry(drying)
Effective Cleaning Procedures
1. A detergent (surfactant or surface active agents) in water lower the surface tension, thus thoroughly wetting the surface
2. It penetrate and soften the soil, hence making it easier to remove by hoses or scrubbing
3. The soil is loosened from the surface of the equipment being cleaned.
4. The loosened soil is dispersed in the wash water.
5. The dispersed soil is rinsed away along with the detergent.
6. Chopping board that used to cut raw beef should be washed thoroughly to prevent cross contamination.
In a dining area, it is important to sanitize all the tables and chairs at the end of the day. Sweeping and mopping the floor is also required to keep the area clean.