Cleaning & Disinfection Principles
Key Terms - DescriptionCleaning : The systematic application of energy to a surface or substance , with the intention of removing dirt. Cleaning does not kill microbes. Energy can be : Kinetic energy physical, mechanical or turbulenceThermal energy hot water Chemical energy detergents
Disinfection : The process of killing pathogenic bacteria , but not spores and all viruses by 99.999% during a time frame greater than 5 but less than 10 mins. Commonly brought about by heat or application of chemicals. Disinfectants have a higher level of germ kill capability for pathogenic bacteria as compared to sanitizers.
Sanitation : The process of reducing microbes to safe levels ie a 99.999% of a specific bacterial test population within 30 secs. Done by heat or chemicals. A sanitizer may or may not necessarily destroy pathogenic organisms.
Sterilization : The process of destroying all microbes including spore forms.
Levels of CLEAN
Cleaning Removal of Visible physical dirt and stains
Disinfection Removal of harmful bacteria / microbes
Sanitation Process in which most or nearly all micro organisms (whether or not pathogenic)
Sterilization Total Germ Kill live (including spores)
Why Clean and Sanitize?
Effective cleaning and sanitation programs are required to achieve the correct level of hygiene in food handling or production facilities. If these are not adhered to there is a greater risk of food becoming contaminated by pathogenic or spoilage microorganisms.
There is also a risk of biofilms forming on factory and food preparation surfaces if these programs are inadequate. Biofilms are complex aggregations of microorganisms and other materials which enhance survival and growth of microorganisms; once formed they are very difficult to remove.
Cleaning and sanitation programs include the following steps:routine procedures performed throughout and at the completion of food processing or preparation on a daily basis periodic procedures required less frequently monitoring to ensure the procedures are performed correctly verification to check effectiveness of the program.
The safety of staff must be considered when developing these programs, including the safe use of chemicals and hot water, and reducing manual labour.Cleaning prior to sanitizing is recommended as it increases the effectiveness of the sanitizing step.
What Should be Cleaned and Sanitized?
All surfaces that may contact the food product, such as utensils, knives, tables, cutting boards, conveyor belts, ice makers, ice storage bins, hands, gloves, and aprons. Surfaces that do not directly contact the product such as walls, ceilings, floors and drains have a profound effect on environment.
What Else Should be Cleaned and Sanitized?
Cleaning tools like brooms, mops, squeegees, buckets, sponges, scrapers, foaming equipment, water guns, etc., should be cleaned and sanitized. Cleaning tools can be a major source of microbial contamination if not cleaned. Cleaning tools should be washed and sanitized after every use. They should be stored clean, dried, and secured.
Factors influencing cleaning & sanitation programType of soil organic , inorganicCondition of soil old soils difficult to cleanSupplies of water - Water hardness difficult in hard water due to formation of scaleWater temperature higher temperatures are beneficialCleaning agent v/s surface being cleaned Agitation or Pressure scouring helps remove outer layer helping deeper penetration of cleaning agent Length of treatment longer exposure is beneficial.Concentration / composition of detergent.supplies of energysupplies of machines, equipment etc.Cultural, religious and traditional valuesClimate conditionsInfrastructure of the processing unit and Requirements for buildingsAwareness level of the staff
Definitions"Food" or Foods: includes any article manufactured, sold or represented for use as food or drink (including water) for humans and any ingredient that may be mixed with food for any purpose whatsoever.
Food Transportation Unit: This includes vehicles, aircraft, ships, containers, boxes, bulk tanks, trailers and any other transportation unit used to transport food.
"Perishable Food" means a food item or ingredient that is susceptible to deterioration or loss of quality due to the microbial or enzymatic actions when such foods or ingredients are subjected to temperature abuse.
"Potentially Hazardous Food" means any food in a form or state which is capable of supporting the growth of pathogenic microorganisms or the production of toxins. Example for such foods involve meat, poultry, seafood, milk and its products.
Cross Contamination: it is the transfer of microbes or other food contaminant from one food to another.
Basic Principles of CleaningWhat is Clean Surface?A clean surface is one that is,Free from Residual film or soilShould not contaminate food productsFree from micro-organisms.What is Soil?Undesirable foreign matter on surfaces.A heterogeneous mixture of many substancesPhysical propertiesChemical propertiesCleaning in Aqueous solutions => complex process of interaction between:physical influenceschemical influencesCleaning:the removal of poorly soluble residues by both water and aqueous surfactant solution (detergent)dissolution of water-soluble residues
Factors affecting cleaningContact timeMechanical actionSurface to clean
Cleaning Performance sensitive to factors like:Type of surfaceStainless Steel, Mild Steel, Aluminium, Brass, Glass & Ceramic, Plastic, Wood etc. Soil typeWater soluble materialWater insoluble materialChemistryWater qualityCleaning techniqueManual or Mechanical.Factors affecting Cleaning Sinners Circle
Mechanical actionChemical actionTimeTemperature
Science behind cleaningDifferent types of soil Oily & Fatty soils, Proteinaceous soils, Carbohydrate soils
Different types of surfacesFabric, Stone, Metal, Ceramic
Cost and ProductivityCleaning within available timeOptimization of costsScientific processes are needed to effect optimal clean
Current Pressures on Food IndustriesAssure the safety of food productsUp-gradation to higher quality productsReduction in CostFSSA had also put pressure on Industries to maintain and upgrade quality standard.
Factors affecting Quality of a Food ProductInput quality (Raw Material, Packaging Material etc.)Manufacturing PracticesPersonal PracticesTransportation PracticesCleanliness and Hygiene Standards etc.
It is next to impossible to achieve quality and safe food without following Proper Cleaning & Hygiene Systems.
Results of Improper CleaningPoor Quality FoodFood-Unsafe for Human ConsumptionIncreased Utility Consumption viz. Steam, Water, Refrigeration etc.Wastages & Reduced Safety Increased level of chemical usageRisk of Brand DamageContinuous deposition of soil on surfaces, which may become difficult to remove even manuallyAffects economy of production adversely
A well designed cleaning protocol shall result in:Improved productivity and organizational profitabilityLesser time for cleaning, thus increased time for productionBetter operational efficiencies with savings in Water, Steam, and Electricity etc.Peace of mind to managementImproved Employee Satisfaction and EfficiencyBetter Safety etc.An effective cleaning can be defined as cleaning to a satisfactory level with optimum costing. Cleaning process comprises of various tools in use, cleaning process and process parameters and cleaning chemicals. Effective cleaning is not achievable without putting a system in place and continuous trainings.
Cleaning and Sanitizing of Food contact Surfaces
Clean, sanitary food contact surfaces are fundamental to the control of pathogenic microorganisms. The contamination of food either through direct or indirect contact with insanitary surfaces potentially compromises the safety of the product for consumption.
The effectiveness of the cleaning and sanitation program relates to the implementation of the cleaning procedure, rather than the type of sanitizer used.
The selection of detergents and sanitizers, their concentrations and the method of application will depend on factors likeNature of soilDegree of cleaning and sanitation requiredType of surface to be cleaned and Type of equipment used for cleaning and sanitation
Cleaning and Sanitation program The cleaning and sanitation program of food contact surfaces typically involves five steps
STEP 1 - Dry cleanSTEP 2 - Pre-rinse (brief)STEP 3 - Detergent application ( may include scrubbing)STEP 4 - Post rinse and STEP 5 - Application of a sanitizer
STEP 1 - Dry cleaningDry cleaning is simply using a brush or squeegee to remove the food particles and soil from surfaces.
Different equipments like brooms, cleaners, water sprays may be used to push the particles form effected surfaces to the drains.
This process may result in significantly removal of unwanted surface matter and thus reducing the load of contamination.
However, it not planned properly may create problems associated with clogged drains, handling of wet waste solids. Its also tends to disperse dirt and bacteria to other areas of plant and may lead to cross contamination to other areas of plant. ( i.e. walls, equipment and tables)
STEP -2 - Pre- rinsingUse of water or any other agent to remove small particles missed in the dry cleaning step and prepares (wet) surfaces for cleaning application.
However, scrupulous removal of particulates is not necessary prior to detergent.