Cleaning & Disinfection Principles

Key Terms

Cleaning Removal of Visible physical dirt and stains. A clean surface is defined as being free from soil (e.g. food residues), free from bad odours, be non-greasy to the touch and have no visible oxidation (e.g. rust).

Disinfection Removal of harmful bacteria / microbes. A sanitized clean surface is defined as a clean surface that is substantially free from pathogenic microorganisms and undesirable numbers of spoilage microorganisms.

Sanitation

Process in which most or nearly all micro organisms (whether or not pathogenic) killed through use of chemicals, heat, ultraviolet rays e.g. Milk is disinfected by heating up to 100degree C for atleast 10 sec. to kill most microbes (but not necessarily their spores) to make it more stable than pasteurized milk

Sterilization

Total destruction of all microorganisms ( whether or not pathogenic) and their spores, usually through the use of drastic methods such as concentrated toxic/ non toxic chemicals (Chlorine, formaldehyde, glutar-aldehydes, etc.), very high temperatures, or intense radiation. A sterilized item cannot support life in any from.

Key Terms - Description

Cleaning : 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.

• Type of soil – organic , inorganic• Condition of soil – old soils difficult to clean• Supplies of water - Water hardness – difficult in hard water due to formation of

scale• Water temperature – higher temperatures are beneficial• Cleaning 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 energy• supplies of machines, equipment etc.• Cultural, religious and traditional values• Climate conditions• Infrastructure of the processing unit and Requirements for buildings• Awareness level of the staff

Factors influencing cleaning & sanitation program

• "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.

Definitions

Basic Principles of CleaningWhat is “Clean Surface”?

– A clean surface is one that is,• Free from Residual film or soil• Should not contaminate food products• Free from micro-organisms.

• What is Soil?– Undesirable foreign matter on surfaces.– A heterogeneous mixture of many substances

• Physical properties• Chemical properties

• Cleaning in Aqueous solutions => complex process of interaction between:– physical influences– chemical influences

• Cleaning:– the removal of poorly soluble residues by both water and aqueous surfactant

solution (detergent)– dissolution of water-soluble residues

Detergent concentration

Detergent composition

Washing temperature

Factors affecting cleaning

Contact time

Mechanical action

Surface to clean

Cleaning Performance sensitive to factors like:• Type of surface

• Stainless Steel, Mild Steel, Aluminium, Brass, Glass & Ceramic, Plastic, Wood etc.

• Soil type• Water soluble material• Water insoluble material

– Chemistry– Water quality

• Cleaning technique• Manual or Mechanical.

Factors affecting Cleaning – Sinner’s Circle

Mechanical action

Chemical actionTime

Temperature Mechanical action

Chemical actionTime

Temperature

Science behind cleaning

Different types of soil – Oily & Fatty soils, Proteinaceous soils, Carbohydrate soils

Different types of surfaces– Fabric, Stone, Metal, Ceramic

Cost and Productivity– Cleaning within “available” time– Optimization of costs

Scientific processes are needed to effect “optimal” clean

Current Pressures on Food Industries

– Assure the safety of food products– Up-gradation to higher quality products– Reduction in Cost– FSSA had also put pressure on Industries to maintain and upgrade quality

standard.

Factors affecting Quality of a Food Product– Input quality (Raw Material, Packaging Material etc.)– Manufacturing Practices– Personal Practices– Transportation Practices– Cleanliness and Hygiene Standards etc.

It is next to impossible to achieve quality and safe food without following Proper Cleaning & Hygiene Systems.

Results of Improper Cleaning

• Poor Quality Food• Food-Unsafe for Human Consumption• Increased Utility Consumption viz. Steam, Water, Refrigeration etc.• Wastages & Reduced Safety • Increased level of chemical usage• Risk of Brand Damage• Continuous deposition of soil on surfaces, which may become difficult to

remove even manually• Affects economy of production adversely

A well designed cleaning protocol shall result in:

• Improved productivity and organizational profitability• Lesser time for cleaning, thus increased time for production• Better operational efficiencies with savings in Water, Steam, and

Electricity etc.• Peace of mind to management• Improved Employee Satisfaction and Efficiency• Better 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 like– Nature of soil– Degree of cleaning and sanitation required– Type 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 clean– STEP – 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 cleaning

• Dry 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- rinsing

Use 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.

STEP – 3 - Cleaning Process

.

Effectiveness of cleaning process will depend on – Type of Soil and Soil Load

Product processedPoint in processing environmentInterior or exterior of equipmentResidence timeTemperature

What is soil?Soil is any unwanted matter on the surface of an object that one desires to be clean. It is undesirable foreign matter on surfaces. In general a heterogeneous mixture of many substances. Special care must be taken to ensure that all soil is removed and that it is not redeposited on the substrate.

- Physical properties - Chemical properties

Characteristics of Food Soils • Soil may be classified as visible and invisible, the latter category being primarily

microorganisms, such as bacteria, yeasts, and molds. • Some food soils can be dissolved in water such as simple carbohydrates (sugars),

some simple mineral salts (NaCl), and some starches. There are also food soils that dissolve in alkali, like proteins, starches associated with proteins or fats, and bacterial films (biofilms). There are food soils that dissolve in acid, like hard water hardness salts (calcium and magnesium salts), and more complex mineral films, including iron and manganese deposits. Some also that dissolve with surfactants, which include fats, oils and greases, many food residues, inert soils such as sand, clay, or fine metals, and some biofilms

Types of soils : - Soils may be either Organic in nature of Inorganic in nature

Organic soils – like from Carbohydrates, Proteins, Fats etc.• Such as those found in animal fats - vegetable oils, blood, protein, starch and

sugars.• tannin, which is commonly found in tea - coffee and wine.

Inorganic soils – Salts, Minerals, like Water hardness salts etc.• Such as scale in kettle; oxidized metal such as rust mineral deposits from food /

drink ( phosphates & oxalates )• calcium salts such as milk stones

Cleaning

Cleaning Process

– Primary step• removal of soil from substrates

– Secondary step• stabilisation of dispersed or dissolved soil in the wash liquor to

prevent re-deposition (long term effect)

• Detergents react with soils to change their chemistry so they will dissolve into the water and be carried away.

• Detergents modify the nature of water so that it may efficiently penetrate, dislodge, disperse and carry away surface soils.

Types of cleaning agents

Four categories of cleaning agents :

Detergents

Solvent cleaners

Abrasive cleaners

Acid cleaners

Cleaning Agents - DetergentsDetergents - A detergent is a surfactant or a mixture of surfactants with "cleaning

properties in dilute solutions." These substances are usually alkylbenzenesulfonates, a family of compounds that are similar to soap but are more soluble in hard water.

Detergents contain surfactants ( surface acting agents ) that reduce surface tension between soil and surface so that soil can be penetrated and removed. Types of detergents

• General Purpose (GP)• Alkaline• Chlorinated ( Chlorinated alkaline);• Acid• Enzymes

• General purpose detergents are mildly alkaline and used to clean up fresh soil from floors , walls , ceilings, equipment, utensils, etc .

• Alkaline or Chlorinated Alkaline detergents are recommended for most processing plant applications and are effective then GP’s. Alkaline detergents range from moderately alkaline (Caustic). Smoke houses, cooker surfaces may require highly caustic cleaning chemicals and application methods.

• Chlorinated products are usually more aggressive in loosening protein based soils or for surfaces that are difficult to clean due to their shape or size, such as perforated storage crates and waste containers. They are also alkaline and many more corrosive. They should not be used on corrodible material such as Aluminium.

• Acid detergents remove inorganic mineral deposits (scale) and stains such as those associated with hard water.

• Emzymes are specific to a given soil type. These detergents are tailored for protein, oil or carbohydrate based oils. Carbohydrate soils mostly occur where breading, batters or starches are used.

• In situations where exposure to excess alkaline or acid conditions are a problem, such as with waste water discharge restriction or equipment susceptible to corrosion enzyme detergents may be an acceptable alternative.

Cleaning Agents – Solvents, Acid cleaners, Abrasive cleaners

Solvent Cleaners :Often called degreasers Alkaline detergents containing grease dissolving agent. Useful for grill back splashes, oven doors, range hoods, etc Effective usually at full strength

Acid cleaners Used on mineral deposits eg. Scale Used in ware-washing machines , steam tables, Used for rust stains and tarnish on copper and brass.

Abrasive cleaners – Contain a scouring agent like silica that help to remove hard – to – remove

soil. Often used on floors or to remove baked on food in pots and pans.

Effectiveness of detergents depends upon

For an effective detergent and soil cleaning effectiveness will depend upon several basic factors

– Contact time– Temperature– Physical disruption ( scrubbing) and – Water chemistry

Contact time: - Detergents do not work instantly but require time to penetrate the soil and release it from the surface. Setting up soak tanks is method to increase the contact time. When working with alkaline and chlorinated detergents, employees should wear appropriate clothing such goggles, tall boots or fully protective suits.

Temperature - Most chemical activities increase with increasing temperature. This generally holds true with detergent efficiency, but with some more exceptions. Many styles of steam cleaners are available are available which allow better penetration of detergents and help in removal of soil. In some case water is used for initially wetting and detergent cleaning and then rinse at 140 – 160 degree F, this improves effectiveness with less risk of food soil left over.

For certain applications such as smoke houses, highly caustic detergent or alkali (Caustic soda) is heated to 180degree F or hotter. The conditions chemically alter and disperse soils such that denatured food residues are not likely to develop.

Disruption (Scrubbing) – Appropriate methods include brushes, pads and pressure spray depending on the application. The selection of proper detergent methods will minimize the need for manual scrubbing.

Water Chemistry – Final rinsing with water to drain the soil, nature, source and type of water used effects the method of cleaning and sanitation.

STEP – 4 – Post Rinse

• During post rinse – water is used to remove detergent and loosen soil from food contact surfaces.

• This process perpares the cleaned surfaces for sanitation.

• All the detergents must be removed in order for the sanitizing agent to be effective.

STEP – 5 - Application of a sanitizerAfter the food contact surfaces are cleaned, they must be sanitized to eliminate or

atleast suppress potentially harmful bacteria. Many type of chemical sanitizers are available. They may or may not require rising before the start of processing, depending upon sanitizer concentration. All sanitizers must be legally approved and used only as per the MSDS (Material safety Data Sheet) provided by the chemical manufacturer.

Application methodWhile using sanitizer a recommended dosage and application method of proportioners

and applicators must be used. These proportioners and applicators can be installed in-line, on-line or at a separate stations.

A range of procedures can be used from manual mixing to fully automated system may be applied.

Some sanitizers such as quaternary ammonium compounds (quats or QAC’s_ may eb applied as foam with same equipment used for detergent foam application.

Effectiveness of sanitation process depends upon: -

• Sufficient contact time and • Coverage of the sanitizer • Dosage of sanitizer• Types of microbes and load of microbes.• Temperature

Sufficient contact time and coverage is sometimes best assured by the use of sanitizers dip tanks for utensils and equipment parts.

Sinks and cleaning sanitations can be applied with protioning devices that mix and deliver sanitizers in the prescribed concentration

Bulk containers or reservoir fitted with auto dosers which minimize maintenance, control of chemicals usage and may reduce monitoring.

For control of common soil microorganisms, such as Listeria and E.coli footbaths are frequently used as a part of plant sanitation program.

An ‘Ideal’ Sanitizer

– Acceptable toxicity– Wide, non-selective spectrum– Rapid action– Reasonably soil tolerant– Non corrosive– Compatible with cleaning materials– Useable in ambient conditions– Easily measured and monitored– Free rinsing– Non-toxic to the environment – Cost effective & safe to handle.

Sanitizers concentration commonly used in Food Plants

Sanitizer Food contact surface

Non food contact surface

Plant water

Chlorine 100-200* ppm 400ppm 3-10 ppm

Iodine 25* ppm 25ppm

Quats 200ppm*ppm 400-800*ppm

Chlorine dioxide 100-200* #ppm 100-200# ppm 1-3#ppm

Peroxyacetic acid 200-315*ppm 200-315ppm

* The higher end of the listed range indicates the maximum concentration permitted without a required rinse ( surface must drain)

# Includes mix of oxychloro compounds

Source 21 CFR 187.1010

Types of Sanitizers

Chlorine Sanitizers

Unfortunately no deal sanitizer exists for every requirement. Chlorine sanitizers

Chlorine and products that produce chlorine comprise the largest and most common group of food plant sanitizing agents. Chlorine sanitizers are effective against a wide range of bacteria and molds. They work well at cool temperatures and tolerate hard water. They are also relatively inexpensive. Household bleach is a solution of sodium hypochlorite, a common form of chlorine.

Chlorine exists in more that one chemical state when dissolved in water. The effectiveness of chlorine sanitizers is proportional to the hypochlorous acid in solution; the most effective chemical form of chlorine.

The percentage of hypochlorous acid increases as alkalinity (pH) is decreased. The pH of some water supplies is artificially elevated, which reduces the effectiveness of chlorine. The Chlorine is very unstable at low pH and may dissipate prematurely without killing bacteria.

Also, NEVER mix Chlorine and Ammonia

Hypochlorite's :- These are the most common chlorine sanitizers. They are available as liquid concentrates on in dry granular form. The granular chlorine products are sometimes reffered to as bleaching powders.

Chlorine dioxide : - Chlorine di-oxide does not form hypochlorous acid but dissolves in water to produce a solution possessing strong oxidizing properties, It can be more effective that chlorine in terms of ability to kill or reduce bacteria and retains some anti microbial function in the presence of organic soils. It is particularly useful for destroying bacteria bio-films. It is also less corrosive to stainless steel and less pH sensitive than chlorine.

Chlorine di-oxide is unstable and must be generated on site. It is potentially explosive and very toxic if improperly controlled – important consideration when selecting this sanitizer.

Disadvantages of chlorine sanitizersThey can be corrosive to equipment and may form organochlorine by – product of

environmental concern effluent. Chlorine is inherently unstable solution, requiring frequent monitoring and replenishing to maintaining adequate concentration.

A common misconception is that the chlorine content of a sanitizer can be confirmed by odour. A used solution that still smells like chlorine may have little or no active chlorine available for killing microbes.

Quaternary Ammonium compounds as Sanitizers

Quaternary Ammonium compounds, or more commonly know as quats or QAC’s. These relatively need a longer exposure time to achieve significant kills. These are very stable and continue to kill bacteria long after most sanitizers lose their effectiveness. They have a stronger residual effect, even in the presence of some soil, they are often selected for footbaths, floors and cooler surfaces. These are effective against Listeria Monocytogenes and are commonly used in facilities that produce ready to eat products.

Limitations• Quats exhibit selective to different types of microorganisms they kill. • On shifting from other sanitizers to Quats, there may be chance incident of

establishment of coliform or spoilage organisms in the environment, which may then transfer to the products.

• These may exhibit effective results when altered with other sanitizers one or two times a week.

• If detergents are not thoroughly rinsed from surfaces prior to applying quats or the sanitizer will be chemically neutralized.

Iodine based sanitizers

• Iodoine based sanitizers, know as Iodophors are formulated with other compounds to enhance their effectiveness They offer desirable features in a sanitizer. They kill most types of micro organisms including yeast and molds even at low concentrations.

• They tolerate moderate contamination with organic soils and less corrosive and pH sensitive than chlorine and are more stable during storage and use. They are less irritating to skin than chlorine and often selected for hand dips.

• Iodophors have an amber to light brown colour when properly diluted which can be useful for monitoring since colour indicates the presence of active iodine. Test strips are available for more precise monitoring.

Disadvantages of Iodophors as sanitizers• The principal disadvantage of iodophors is staining, especially on plastics• These sanitizers take a longer time to kill microorgansms at low temperatures than

does the chlorine and is rapidly vaporized and inactivated above 120degree F. Iodophors must be specially formulated for use with hard water.

Acid sanitizers These include acid anionic and carboxylic and peroxyacetic acid types. The advantage in

application of these sanitizers is that these are stable at high temperatures or in presence of organic matter. Being acids, they remove inorganic solid, such as hard water mineral scale, while sanitizing. These are commonly used in CIP or mechanical cleaning systems.

The Carboxylic acid sanitizers, commonly known as fatty acid sanitizers, these are generally more effective than acid – anoinic against a range of microorganisms types.

Peroxyacetic acid are produced by combining hydrogen peroxide and acetic acid. This sanitizers is highly effective against most microorganisms of concern, especially in biofilms which would otherwise protect bacteria. They are fast acting even at low temperatures, tolerate some organic soil and degrade to form environmentally safe products.

Disadvantages of acid sanitizers – Water chemistry is important since these sanitizers are inactivated by certain metal ions, such as iron, and become quite corrosive when mixed with water containing high chloride levels e.g. wells with high salinity levels.

Other Sanitizing Agents

Other sanitizing agents include ozone, ultraviolet light and hot water. Ozone is an unstable oxidizing gas that must be generated on-site, contributing to its relatively high cost. It is a more aggressive sanitizer than chlorine but requires careful monitoring to prevent the release of excessive levels of the toxic gas.

Ozone, like chlorine, is dissipated when in contact with organic soils. It can be injected into water system, as an alternative to chlorine gas, to make it safe for processing.

Ultraviolet ( UV ) irradiation is sometime used for treating water, air or surface that can be positioned in close proximity to UV generating lamps. Ultraviolet does not penetrate cloudy liquids or below to surfaces of films or solids.

It has no residual activity and cannot be pumped or applied onto equipment like most chemical sanitizers.

Sanitizers - sanitizing methods

Spray Sanitizing Use of spray to sanitize equipment surfaces

CIP Sanitizing Sanitizing by circulation of the chemical agent inside pipeline and equipment.

Immersion / COP Sanitizing

Sanitizing equipment by immersion in a tank of sanitizing solution

Fogging Fogging the chemical agent to sanitize the air and surfaces in a room.

Chlorine All food contact surfaces, sprays, CIP, fogging

Mixed Halogens All food contact surfaces, CIP, spray sanitizing

Iodine All food contact surfaces, spray, CIP, approved as hand dips.

Peracetic Acid All food contact surfaces, CIP, especially cold temperatures and Carbon di oxides environments.

Acid Anionics All food contact surfaces, CIP, spray, combined with sanitize and acid rinse step into one.

QUATS All food contact surfaces, mostly used for environmental control: walls, drain and tiles

Cleaning methods in Food industry

Manual & Mechanical

•Wet & Dry

•Immersion cleaning

•COP

•CIP

•High Pressure sprays

Manual and Mechanical - Wet Cleaning Methods

Manual - Wet mopping – One/two bucket systems, apply detergent solution to

emulsify/absorb dissolved dirt. Longer dry time

Manual Scrubbing - Single disc w/water tank e.g. Stripping coated

floorings

Automatic Scrubbing –Machine scrub/dry floor in one operation. Cleaning of

medium to large areas.

Wet vaccum cleaning –Pick-up residual liquids /water, drying floor

Manual cleaning Advantages and Disadvantages

Manual Cleaning Advantages Parts can be cleaned without complete immersion in the cleaning solution. Additional cleaning equipment, such as wash and rinse tanks, is not necessary. Waste disposal requirements are kept to a minimum.

Manual Cleaning Disadvantages It is a labor-intensive process, require additional time to complete. Cleaning efficacy ?? Cleaning Solution consumption is higher, Limitation on use of aggressive chemical. There is no reclaim of cleaning solution.

This is how Foam is Generated

H2030 - 50 psi

ChemicalAir

40 - 60 psi

Wet Cleaning - Foam / Gel Technology

•Use of high foaming solution to increase the retention time on the vertical surfaces

•Gels are used to further increase over foam the retention time on the vertical surface

Mechanical Cleaning and Sanitation

Advantages of Foam Cleaning Process

Mechanized Cleaning Process Applied at Low pressures High chemical / soiling contact time Safe for operators as little aerosol is formed Hence more aggressive chemicals can be used Uses significantly less water than pressure cleaning Reduces cleaning time Minimizes risk of cross contamination Improved Cleaning efficiency Better cleaning economy Improved working environment Satisfied cleaning personnel Better environmental accountability

Centralised Foam Cleaning systemsCentralised Foam Cleaning systems•No concentrated chemicals in production area. •Less handling of chemicals. One setting of concentration

De centralized Foam Cleaning System•Al operators can select rinse, foam or disinfection. •Detergent at each cleaning point

Mechanical – Dry Cleaning

• Manual or Automated• Use of Brooms/ Shovels• Use of automated Vaccum cleaners• Process used where wet cleaning is not possible• Areas manufacturing water sensitive products

Immersion Cleaning• This is the type of cleaning in which the parts to be cleaned are placed in the

cleaning solutions to come in contact with the entire surface of the parts.

• Immersion cleaning is preferred for parts that must be placed in baskets and for processes requiring a long soaking time because of the type of contamination to be removed or the shape of the parts to be cleaned.

It is the most effective method, even if not the fastest one, and can be used with any type of cleaner for any process, heated or at room temperature. Immersion washers can be portable or stationary; single or multi-compartment; and are available with a variety of options, controls and valve configurations including CIP capability. The important aspects during design of immersion washer should be

– To minimize cycle time– Lower chemical usage– Reduce water and utility costs– Performance for immersion cleaning can be improved by moving the parts

within the liquid or with agitation of the liquid, mechanically or with the addition of ultrasonic energy.

Mechanical – COP (Cleaning Out Of Place)Cleaning Out of Place is defined as a method of cleaning equipment items by

removing them from their operational area and taking them to a designated cleaning station for cleaning. It requires dismantling an apparatus, washing it in a central washing area using an automated system, and checking it at reassembly.

Automated Parts Washer

Automated controls:- Contact Time- Temperature

COP Mechanical Action (agitation)

Side Jet Action Push - Pull Action

Combination

Mechanical cleaning - CIP

Cleaning in place can be described as the cleaning of equipment and vessels at the same place without movement of them to a different place. The cleaning agents can be transferred to the vessel or equipment types either thorough fixed piping or flexible hoses. The CIP process can consist of the following elements:

• Supply pump• Return pump• Heat exchanger with Black/Plant steam supply• Chemical tanks i.e Acid, Alkali tanks• Supply Pressure gauge or transmitter• Supply temperature sensors• Conductivity meter with sensor

C.I.P. Basic Requirements

Mechanical cleaning – High Pressure cleaning

Use of High pressure spray device assists in the removal of soil

High Pressure Advantages

• Good for Removal of Difficult or burnt soil

• Lowest Water Usage

• Works Against Broad Range of Soils

Cleaning Standards

Cleaning standards can be determined through:

Visual test

General appearance

Microbiological test contact agar method swab/rinse method rapid hygiene test.

Verification of cleaning and sanitation methodsMonitoring to assure a clean and sanitary processing environment processing is required

regulation. Various methods are used by different organizations to verify effectiveness of cleaning and sanitation programms.

Commonly used methods include 1. Test strips – Strips are simply are soaked directly in the solution to be tested, a

change in colour indicates the presence of the sanitizers, the shade or intensity of which relating to the concentration of the chemical. These are very rapid, low cost, do not require any laboratory equipments or chemicals, can be performed on site, and require very little training. E.g. Chlorine indicator test strips.

2. Contact plate – Contact plates contain agar which has a convex surface. These plates are pressed against the surface of equipment then incubated. Examination of the plate will give an organism count and individual colonies can be lifted from the plate and identified.

The surface of the equipment touched by the contact plate must be cleaned of any agar residue. This method is used for verifying periodic effectiveness of cleaning and sanitizing plant surfaces. The test procedure is very simple and requires no additional special equipment and little training. Most contact plates are simply touched to the surfaces to be tested then covered with a protective cap.

3. Swabbing - A sterile cotton or calcium alginate swab is wetted in sterile buffer, saline solution, or broth and rubbed over a measured portion of the surface of the sanitized equipment. The swab is then either streaked across an agar plate or placed into a sterile broth tube.

The plate or tube is incubated for the appropriate length of time. Examination of the plate will give an organism count and the individual colonies can be lifted from the plate and identified. Tubes are examined for turbidity. This is a pass / fail test. Swabbing is very useful for irregular surfaces or curved equipment

Limitation to microbiological testing methods 1. These are slow and do not reveal problem in time to correct them prio to

processing. 2. Manual errors may lead to variation of results.3. Test Protocols and test method are easily available. However, results may not

often be conclusive due to lack of reference data.

4. Luminometry (bioluminesence) is based on the enzymatic reaction responsible for firelfly’s light. In this testing method, the brightness of light is propotional to the amount of bacteria and food debris on the surface. In a typical test, a food contact surface is swabbed following sanitation.

Material is swabbed and is placed inside an instrument that measures light production. The instrument generates a value related to the quantity of cellular material, such as bacteria. In some instances the residual food can provide high reading when the load on the surface is quite low. Microbiological techniques, are required for ore specific testing such as coliform bacteria count.

5. Final Rinse Test: Water of known microbiological quality and volume is rinsed through the equipment. The water is recovered and filtered via membrane filtration technique. The membrane is placed onto a plate and incubated. Examination of the plate will give an organism count and individual organisms can be identified. Note that rinse water analysis may not detect the presence of biofilm on equipment surfaces.

Cleaning & Sanitation – Microbiological Aspect• Microbes need Water and Food for growth.• Most of food products are high in water activity.• Food product contact surfaces may harbor microbes and provide the shield to

exterior factors.• Bacteria take exponential route for the growth and one bacteria doubles in average

20 minutes.• A non-clean, improperly clean surface may create a risk to food product and its user.• Critical for surfaces, coming in direct contact with food.• A suitable disinfectant should have

• Broad Spectrum for killing microbes (viz. all groups – Bacteria, Yeasts, Molds, Viruses etc., Gm+ve & Gm-ve etc.)

• Should be sporicidal if required• Rinse free or easy to rinse• Should not affect MOC• Safe and easy to use

• Detergent-disinfectant can provide cleaning and sanitation simultaneously, thus saves water, energy, time and manpower

Monitoring steps in the cleaning program should include:• Visual inspection post cleaning to ensure any visible food residues have been

removed• Temperature checks for water and chemical solutions (using a calibrated

thermometer or temperature recorder) to ensure they are within the ranges specified in the Standard Operating Procedures (SOP)

• Concentrations of detergents and sanitizers are within the ranges specified in the SOP

• Timing devices used to ensure adequate contact times are operating correctly• Records are checked against procedures outlined in the SOP.

Verification of the effectiveness of the program is required on an ongoing basis and ranges from simple procedures that can be performed in-house to more complex testing that may need to be outsourced:

• looking, touching and smelling –• Microbiological testing of equipment and surfaces • ATP (adenosinetriphosphate) fluorescence testing can be used to detect the

presence of microorganisms and food residues • Equipment used for cleaning and sanitizing should be kept in good working order

so it does not become a source of contamination itself.

Cleaning and sanitation schedulesCleaning and sanitation program and its schedule should be based on the importance

of the processes, its impact on food safety, the intensity and priority needed.

The schedules should define when and how different items and areas should be cleaned and who to do the cleaning.

• What is to be cleaned• Who is to clean it• When it is to be cleaned• How it is to be cleaned• The time necessary to clean it• The chemicals used• Materials and equipment to be used• The cleaning standard required• The precaution to be taken• The protective clothing to be worn• Who is responsible for checking and recording that it has been cleaned.

END OF PRESENTATION