CLEANING, HYGIENE AND SANITIZING OPERATIONS

CLEANING, HYGIENE AND SANITIZING OPERATIONS

Introduction

Drinking, eating, washing, excreting – these are things we do every day of our lives. But the way we do them can have a major impact on our health. Good hygiene practices are an essential part of daily life and we all need to understand what hygiene means, why it’s important for our health and wellbeing, and how we can change our behaviour to safeguard our health. Promoting good hygiene in your community and educating people in ways to protect themselves and their families from ill health is one of the most important aspects of your work.

Hygiene - a set of preventive measures for good health - has become an essential part of our lives. Today it seems natural to wash our hands, vaccinate our children or drink safe water, but it hasn't always been so. The concept of hygiene, closely linked to popular beliefs and to customs as well as to scientific and medical knowledge, has evolved. The history of hygiene can be divided into two main phases separated by the biological revolution, when micro-organisms and their role in diseases were discovered. Beyond this dividing line, hygiene became a scientific discipline supported by irrefutable observations. Many misconceptions were swept aside to make way for practices which play a large part in extending our life expectancy.

Importance

Why Clean?

 Effective cleaning of equipment in the food processing industry reduces chances for contamination of food during preparation, processing, storage and serving. The first step in the practical application of a sanitation program is to render the surface clean. This will reduce to a degree the number of microorganisms present and eliminate one essential need for life - "food". The surviving microorganisms will be left unfed, unprotected and highly susceptible to final disinfecting and sanitizing treatment. Cleaning minimizes attraction of other lower forms of life, increases life of equipment, improves employees morale and efficiency and is important for aesthetic considerations.

Why disinfect or sanitize?

 The primary reason for the application of effective sanitizing procedures is to reduce those disease organisms which may be present on equipment or utensils after cleaning to a safe level as may be judged by public health requirements, and thus prevent the transfer of such organisms to the ultimate consumer.

 In addition, sanitizing procedures may prevent spoilage of foods. The existence of any microbe in a food environment must be strictly controlled. The so-called harmless microbe under the proper conditions can become a nuisance. Food can become contaminated, reproduce to sufficient numbers to cause off-colours, off-odours and off-flavours. Unsightly growth often results in waste and loss of precious dollars. Many kinds of bacteria can cause slime formation on meats, poultry, fish and similar edibles.

Difference between cleaning and sanitizing

Cleaning is the process of removing food and other types of soil from a surface, such as a dish, glass, or cutting board. Cleaning is accomplished using a cleaning agent that removes food, soil, rust stains, minerals, or other deposits. The right cleaning agent must be selected because not all can be used on food-contact surfaces. (A food-contact surface is defined as a surface of equipment or utensil with which food normally comes into contact or a surface of equipment or a utensil from which food may drain, drip, or splash into a food or onto a surface normally in contact with food.) 

Sanitizing is the process of reducing the number of microorganisms that are on a properly cleaned surface to a safe level. A safe level is defined as a 99.999% reduction of the number of disease microorganisms that are of public health importance. Sanitizing is accomplished by using heat, radiation, or chemicals. Unless the item to be sanitized is effectively cleaned, it is impossible to obtain close contact between the sanitizer and the surface to the sanitized.  Also, some chemical sanitizers, such as chlorine and iodine, react with organic matter and so will be less effective when the surface is not properly cleaned.

Cleaning means the removal of dirt, food residue, and any other materials from a surface, utensil, or equipment using detergents or other cleaning aids and either mechanical or detergent scrubbing actions, followed by rinsing.

Sanitizing means the application of a chemical or heat to a clean surface that will kill microorganisms. The definitions section of the GMP regulation states that: Sanitize means to adequately treat food-contact surfaces by a process that is effective in destroying vegetative cells of microorganisms of public health significance, and in substantially reducing numbers of other undesirable microorganisms, but without adversely affecting the product or its safety for the consumer.

Disinfecting is a process that Kills disease causing germs on surfaces. This process is accomplished with germicides or physical agents such as high heat. Most surfaces need to be cleaned, some need to be sanitized and very few need to be disinfected.

Principles of cleaning

Effective cleaning and sanitization of food contact surfaces of equipment and utensils serve two primary purposes:

1.      Reduces chances for contaminating safe food during processing, preparation, storage and service by physically removing soil, bacteria and other microorganisms; and

2.      Minimizes the chances of transmitting disease organisms to the consumer by achieving bacteriologically safe eating utensils.

There are five basic principles of cleaning that must be used in conjunction with each other:

- TIME

- TEMPERATURE

- MECHANICAL ACTION

- CHEMICAL ACTION

- PROCEDURES

These five must be carefully balanced in order to accomplish the stated job most efficiently and most economically. Should any of the five basics be decreased in strength, one of the others will have to be increased in order to accomplish the job. It is critical for operators to maintain the proper balance of the basics.

A specific cleaning compound should be selected for its special cleaning properties. Also, a compound that is effective for one application may be ineffective for other uses. In addition to being effective and compatible with its intended use, a cleaning compound should fit the needs of the establishment.

There are few principles that should be following for good practice:

·         All food contact surfaces must be cleaned and sanitized after every use, when there is service interruption during which contamination is possible or at regularly scheduled intervals if the surfaces are in constant use.

·         A specific cleaning compound should be selected for its special cleaning properties. A compound that is effective for one application may be ineffective for other uses.

·         In addition to being effective and compatible with its intended use, a cleaning compound should fit the needs of the establishment.

·         Worn and pitted porcelain, rusty metals, or seriously soiled floors can be effectively cleaned with abrasives. Abrasives should be used cautiously in a foodservice facility. Because they can mar a smooth surface, they should be used sparingly on food contact surfaces.

·         If soil is attached so firmly to a surface that alkaline or acidic cleaners will not be effective, a cleaner containing a scouring agent, usually finely ground feldspar or silica, is used to attack the soil.

·         If not continuous, cleaning must at least be performed at regular and frequent intervals so that a consistently good quality of product is maintained.

·         Food residues may be dry particulate, dried-on, cooked-on, sticky, fatty or slimy. Such residues may be best removed by physical means or by the use of hot or cold water supplemented with detergents.

Cleaning steps

There are eight basic steps for manual cleaning and sanitizing of a typical food-service facility:

1.      Clean sinks and work surfaces before each use.

2.      Scrape heavy soil deposits and pre-soak to reduce gross deposits that contribute to deactivation of the cleaning com-pound. Sort items to be cleaned, and pre-soak silverware and other utensils in a solution designated for that purpose.

3.      Wash items in the first sink in a clean detergent solution at approximately.

4.      Wipe all non-food contact surfaces.

5.      Periodically wring out cloths used for wiping down stationary equipment and surfaces in a sanitizing solution. Keep them separate from other wiping cloths.

6.      Air-dry all cleaned parts before reassembling.

7.      Clean stationary items that are designed to have a detergent and sanitising solution pumped through-out according to the manufacturer’s instructions. High-pressure, low-volume cleaning equipment can be used for cleaning, and spray devices can be used for sanitizing. For sanitizing, spray for 2 to 3 minutes with double-strength solution of the sanitizer.

8.      Any wooden cutting boards should be scrubbed with a nontoxic detergent solution and stiff-bristled nylon brush (or a high-pressure, low-volume cleaning wand). Also, a sanitizing solution should be applied after every use. As wooden cutting boards reflect wear from cuts and scars, they should be replaced with polyethylene boards. Wooden cutting boards should not be submerged in a sanitizing solution.

Cleaning frequency

The frequency of cleaning and sanitization is determined by the types of activities conducted in any given area. Qualified personnel should visually monitor each area routinely. Cleaning and sanitizing schedules can be adjusted and remedial action can be taken as needed.

Cleaning Frequency

a)         Tableware shall be washed, rinsed, and sanitized after each use.

b)         To prevent cross-contamination, kitchenware and food-contact surfaces of equipment shall be washed, rinsed, and sanitized after each use and following any interruption of operations during which time contamination may have occurred.

c)         Where equipment and utensils are used for the preparation of potentially hazardous foods on a continuous or production-line basis, utensils and the food-contact surfaces of equipment shall be washed, rinsed and sanitized at intervals throughout the day on a schedule subject to the approval of the regulatory authority.  This schedule shall be based on food temperature, type of food, and amount of food particle accumulation.

d)         The food-contact surfaces of grills, griddles, and similar cooking devices and the cavities and door seals of microwave ovens shall be cleaned at least once a day except that this shall not apply to hot oil cooking equipment and hot oil filtering systems.  The food-contact surfaces of all cooking equipment shall be kept free of encrusted grease deposits and other accumulated soil.

e)         Non-food-contact surfaces of equipment shall be cleaned as often as is necessary to keep the equipment free of accumulation of dust, dirt, food particles, and other debris.

http://www.ilga.gov/commission/jcar/admincode/077/077007500E08000R.html

 All equipment should have a regular cleaning and sanitization schedule. The frequency should be determined based on several factors:

·         Product vulnerability to contamination

·         Type of equipment used

·         Difficulty in removing product from the equipment

·         Whether continuous process batching is being performed

Waste Disposal Area

Provisions should be made for regular and timely removal and disposal of waste out of the proximity of finished products, components, and manufacturing areas to minimize the risk of microbial contamination.

·         Refuse for disposal in designated containers using plastic liners.

·         Construct containers so that they are leak-proof and rustproof, and cover whenever possible.

·         Empty refuse containers at a minimum of once daily and clean it when necessary prior to reuse.

·         Clean spills immediately and remove debris from the manufacturing areas.

·         Use disposable towels and discard immediately after single use. Do not use rags.

·         Isolate waste disposal areas from manufacturing, and routinely clean and sanitize to minimize odours.

·         Dispose of product or process waste in accordance with current government regulations.

·         All hazardous waste, including spills, should be handled per the facility hazardous waste management plan.

 Cleaning equipment and supplies

Store cleaning equipment and supplies properly in a clean area. Maintain the supply area in an orderly manner. Separate supplies and equipment for lavatory cleaning from other cleaning supplies.

Walls, ceilings, pipes, and fixtures

Clean and/or sanitize on a scheduled basis (for example, monthly, quarterly or more frequently, if needed). Vacuum to remove loose material.

Floors

Clean floors on a scheduled basis, to include the following

·         Vacuum and/or sweep frequently.

·         Minimize airborne dust during clean up.

·         Wet mop or machine scrub on a predetermined schedule, Sanitize as appropriate.

·         Promptly clean up spills of raw materials, product or packaging components.

The factors that affect cleaning efficiency and frequency

1.      Type of Soil to be removed

2.      Water quality.

3.      Water Temperature

4.      Contact Time

5.      Water Velocity

6.      Sequestering Agent

7.      Concentration of the detergent

                                                                                                                            

Type of Soil to be removed

Food Deposits:

Fat & Grease – Alkaline detergent

Protein & Blood – Alkaline detergents and Enzyme detergents

Sugar & Carbohydrates – Water

 Minerals Deposits, rust – Acid detergents

Soils contains microorganism such as bacteria, viruses, yeasts and moulds thus the use of sanitizer is recommended. By identifying the type of soil involved, we can easily determine the type of detergent suitable to remove the soil effectively and economically.

Water Quality

Water is the main component in cleaning materials. Water use must be potable (safe to drink) Water must not be hard water as it reduces the effectiveness of detergents and leaves scale deposits on the surface of equipment. Hard Water: Water with high mineral content. Soft water:  water with low mineral content. Hard water does not pose any harm to one’s health but poses serious problems in industrial setting.

Water Temperature

Depends on the type of detergent:

Heat stable type – Between 54°C – 71°C

Cold water type – Tap water temperature

Temperature of water needs to be hot enough to decrease the strength of the bonds that hold soil to the surface being cleaned. However it should not be too hot such that the soil gets baked onto the equipment surface.  At higher temperature of the water, the effectiveness of cleaning will be high.

Water Velocity

The velocity of the cleaning solution helps in removing soil from food surfaces.

The importance of the velocity cleaning solution decreases as the effectiveness of the detergent increases.

Contact Time

Cleaning efficiency increases with longer contact time between the cleaning solution and the surface to be cleaned.

The amount of scrubbing necessary to remove soil decreases with increase contact time between the cleaning solution and the surface to be cleaned.

Sequestering Agent or Chelating Agent:  It is an inorganic ingredient blended with detergent to prevent the precipitation of unstable salts (Calcium and Magnesium Ions) that leads to the formation of scale (or deposits). Helps softened hard water so that it is suitable to be used for cleaning. In another word we can say Sequestering agents or Chelating agents remove a metal ion from a solution system by forming a complex ion that does not have the chemical reactions of the ion that is removed. Sequestering agents or Chelating agents are used to eliminate water hardness and heavy metals, such as iron and copper which can affect the scouring process.

Concentration of the detergent

Increase the concentration of the detergent increases the efficiency of soil removal from the equipment surface. However, beyond a certain limit, the higher the concentration neither increase nor decrease cleaning efficiency. Follow the recommended usage of detergent provided by the manufacturer.

Types of Cleaning Agents

Not all cleaning agents can be safely used on food-contact surfaces. Examples of those that should not be used include: glass cleaners, some metal cleaners, tub and tile cleaners. The label should indicate if the product can be used on a food-contact surface.

Secondly, the ideal cleaning agent must be selected to make cleaning easy. Cleaning agents are divided into four categories:

•Detergents -- All detergents contain surfactants that reduce surface tensions between the soil and the surface, so the detergent can penetrate quickly and soften the soil. Examples include Dawn and Joy dishwashing detergent and automatic dishwasher detergents.

•Solvent cleaners -- Often called degreasers, solvent cleaners are alkaline detergents that contain a grease-dissolving agent. These cleaners work well in areas where grease has been burned on. Examples include Fantastic.

•Acid cleaners -- Use on mineral deposits and other soils alkaline cleaners cannot remove, these cleaners are often used to remove scale in warewashing machines and steam tables.

•Abrasive cleaners -- Use these cleaners to remove heavy accumulations of soil often found in small areas. The abrasive action is provided by small mineral or metal particles, fine steel wool, copper, or nylon particles. Some abrasive cleaners also disinfect. Examples include Ajax and Comet.

Principle of sanitation

1.      Washing equipment and utensils until visibly clean does not complete the process. A sanitization step must also be completed.

2.      Proper sanitisers must be use.

3.      No rinsing or any other cleaning process should take place after the sanitizing process.

4.      Equipment and utensils must be air dried only.

5.      Swabbing can be utilised when the sanitising solution is twice the strength required.

6.      Thermometers and test kits are required to ensure the sanitation status.

7.      Before returning to work every one should wash their hands .

8.      Any spilled materials or products must not be returned to the production area.

9.      Waste materials must be placed in containers (with tight-fitting covers) suitable for disposal.

10.  Each employee is required to keep the immediate work area clean and tidy.

11.  Tobacco use is forbidden, except in designated areas.

12.  Spitting is prohibited anywhere in the area.

Factors affecting sanitation

The primary reason for the application of effective sanitizing procedures is to destroy those disease organisms which may be present on equipment or utensils after cleaning, and thus prevent the transfer of such organisms to the ultimate consumer. In addition, sanitizing procedures may prevent spoilage of foods or prevent the interference of microorganisms in various industrial processes which depend on pure cultures.

There are two generally accepted methods of providing for the final sanitization of a utensil after effective removal of soil, heat and chemical.

A. Hot water - an effective, non-selective sanitization method for food-contact surfaces; however, spores may remain alive even after an hour of boiling temperatures. The microbial action is thought to be the coagulation of some protein molecules in the cell. The use of hot water has several advantages in that it is readily available, inexpensive and nontoxic. Sanitizing can be accomplished by either pumping the water through assembled equipment or immersing equipment into the water. When pumping it through equipment, the temperature should be maintained to at least 171°F. (77°C) for at least 5 minutes as checked at the outlet end of the equipment. When immersing equipment, the water should be maintained at a temperature of a least 171°F (77 °C) or above for 30 seconds.

B. Steam is an excellent agent for treating food equipment. Treatment on heavily contaminated surfaces may cake on the organic residues and prevent lethal heat to penetrate to the microorganism. Steam flow in cabinets should be maintained long enough to keep the thermometer reading above 171°F (77°C) for at least 15 minutes or above 200°F.  For at least 5 minutes. When steam is used on assembled equipment, the temperature should be maintained at 200. For at least 5 minutes as checked at the outlet end of the assembled equipment.

Chemical sanitizers

The use of chemicals is the most common method for killing food poisoning bacteria however, heat can also be used. Food businesses must make sure that any sanitizer used is ‘food grade’ – safe for food contact surfaces. The table below lists examples of common sanitizers.

Chemical sanitizers are generally chlorine-based or ammonium-based compounds. Products suitable for using in food businesses are available from commercial chemical suppliers and retailers. Only use chemical sanitizers that are designed for using in food premises. Some sanitizers require residues to be rinsed off food contact surfaces after use. Dilution rates, contact times and safety instructions vary from product to product. When using and storing chemicals (including bleach), always follow the manufacturer’s instructions. Items that can fit in the sink can be washed and cleaned in the left-hand bowl. They can then be immersed in a chemical sanitizer solution in the right hand bowl.

Chemicals used in sanitising

Hypochlorite

Effectiveness, low cost and ease of manufacturing make hypochlorites the most widely used sanitizers. Sodium hypochlorite is the most common compound and is an ideal sanitizer, as it is a strong oxidizer. Hypochlorite cause broad microbial mortality by damaging the outer membrane, likely producing a loss of permeability control and eventualities of the cell.

Chlorine Dioxide

This inorganic compound is a broad sanitizer effective against bacteria, fungi and viruses. Chlorine dioxide is an oxidizer that reacts with the proteins and fatty acids within the cell membrane, resulting in loss of permeability control and disruption of protein synthesis.

Iodophor

These compounds are less active than hypochlorites but are effective sanitizers and disinfectants. Iodophors attach to the sulphurs of proteins such as cysteine, causing inactivation and cell wall damage.

Sanitizing Food Contact Surfaces

Sanitizing is a procedure to treat food-contact surfaces that destroys most disease producing bacteria and viruses, substantially reduces the number of other undesirable organisms, and does not adversely affect the product or its safety for the consumer. Sanitizing can be done with heat or with chemicals.

Sanitizing does not affect bacterial spores—that is beyond the capability of the process. A sanitizer will not sterilize a food-contact surface or a water system. Sterilization refers to the statistical destruction and removal of all living organisms, including spores. The official definition of sanitizing for food product contact surfaces is a process which reduces the contamination level by 99.999% (5 logs) in 30 sec. Disinfectants are stronger chemicals that produce a much larger reduction of microorganisms. They are generally not used in food applications.

Dishwasher

To sanitise effectively with a dishwasher:

·         Use the correct type of detergent or sanitizer,

·         Use the hottest rinse cycle available (economy cycle on a domestic dishwasher is not adequate),

·         Look over equipment and utensils when removing them from the dishwasher to check they are clean,

·         Clean the dishwasher so there is no build-up of food residues, and

·         Regularly maintain and service the dishwasher according to the manufacturer’s instructions.

A hand sanitizer or hand antiseptic is a supplement or alternative to hand washing with soap and water. Various preparations are available, including gel, foam, and liquid solutions.

Food contact surface is the surface of equipment and utensils with which food normally comes into contact and those surfaces from which food may drain, drip or splash back onto surfaces normally in contact with food.

Definitions for Terms   

1.      Acidity -- the degree or measure of the amount of acid in a solution or substance; measurement can be expressed in parts per million, percentage, or pounds or grains per gallon.

2.      Acids -- they are chemicals that form hydrogen ions in solution giving a pH less than 7.

3.      Acids, strong -- they are substances that release high concentrations of hydrogen ions in a solution giving a very low pH. Examples include muriatic and sulphuric acids.

4.      Acids, weak -- they release moderate to low concentrations of hydrogen ions in a solution, giving a moderately low pH.  Examples include organic acids, such as lactic and acetic acids.

5.      Alkalinity -- the degree or measure of the amount of alkali in a solution or substance.

6.      Alkalis -- they are chemicals that release an excess of hydroxyl ions in a solution giving a pH of greater than 7.

7.      Alkalis strong, -- they are substances that release high concentrations of hydroxyl ions in solution giving a very high pH.  Examples include caustic soda and caustic potash.

8.      Alkalis, weak -- they release moderate to low concentrations of hydroxyl ions giving moderately high pH values.  An example is sodium bicarbonate.

9.      Antiseptic -- an agent used against sepsis or putrefaction in connection with human beings or animals.

10.  Automated Cleaning (CIP): Clean-in-place: Cleaning internal surfaces of production equipment without disassembly.

11.  Bactericide -- an agent that causes the death of a specific group of microorganisms.

12.  Bacteriostat -- an agent that prevents the growth of a specific group of microorganisms but does not necessarily kill them.

13.  Buffer - any material that moderates the intensity of an acid or alkali in solution without reducing the quantity of acidity or alkalinity.

14.  Chelation - The action of an organic compound attaching itself to the water hardness

Particles and inactivates them so they will not combine with other material in the water and precipitate out. A substance that removes a metal ion from a solution system by forming a complex ion that does not have the chemical reactions of the ion that is removed can be a chelating or a complexing agent.

15.  Corrosion-resistant materials - Materials that are capable of maintaining their original surface characteristics under prolonged use, including the expected food contact and the normal use of cleaning compounds and sanitizing solutions.

16.  Disinfectant -- an agent that is applied to inanimate objects; it does not necessarily kill all organisms.

17.  Dispersion -- the action of breaking up of mass into fine particles, which are then suspended and flushed off the surface and/or equipment.

18.  Dissolving -- refers to the mixing of a liquid and a solid to produce a homogeneous solution.

19.  Easily cleanable -- surfaces must be readily accessible and made of such materials and finish and so constructed these chemical residues may be effectively removed by the cleaning process.

20.  Emulsification -- the action of breaking up fats and oils into very small particles which are uniformly mixed in a water solution, preventing the clumping or clustering of the particles; in a stable emulsion the oil particles are suspended for a long period of time.

21.  Germicide - an agent that destroys microorganisms.

22.  Peptizing - the physical formation of colloidal solutions from soils which may be only partially soluble; this action is similar to dispersion but is particularly applicable to protein soils.

23.  ^pH - It  is a measure of the activity of the (solvated) hydrogen ion. ^pH, which measures the hydrogen ion concentration, is closely related to, and is often written as, ^pH.

24.  ^pH scale – it measures how acidic or basic a substance is. The ^pH scale ranges from 0 to 14. A ^pH of 7 is neutral. A ^pH less than 7 is acidic. A ^pH greater than 7 is basic.

25.  Rinsing -- condition of a solution or suspension which enables it to be flushed from a surface easily and completely; action occurs by reducing the surface tension of the water being used.

26.  Sanitization -- the process of reducing microbiological contamination to a level that is acceptable to local health regulations.

27.  Sanitizer -- an agent that reduces the microbiological contamination to levels conforming to local health regulations.

28.  Saponification -- a chemical reaction of esters into acids or alcohols by the action of alkalis or acids; use of alkalis with animal or vegetable fats results in soap.

29.  Sequestration -- the chemical action resulting in the binding of a metal ion in solution with the formation of a soluble and stable complex; when the activity is performed to control water hardness with formation of a typical organic ring structure, the action is termed "chelation."

30.  Sterilization -- the process of destroying all microorganisms.

31.  Surfactant -- a chemical product whose molecules are able to modify the properties of an interface, e.g. liquid/liquid, liquid/air by lowering (reducing) the surface tension, allowing water to contact all surfaces.  The four major types of surfactants used in detergents are:  anionic, cationic, non-ionic, and amphoteric.

32.  Suspension -- the action which keeps insoluble particles uniformly distributed in a solution, preventing them from settling and forming deposits and making it easier to flush them from equipment.

33.  Water hardness -- relates to water containing mineral constituents which form insoluble products, resulting in poor lathering of soap; principally caused by salts of calcium, magnesium, and iron.

34.  Water softening -- the process of removing the calcium and magnesium salts, preventing the precipitation of insoluble carbonates and hydroxides.

References: Principles of Food Sanitation (Fifth Edition) Norman G. Marriott and Robert B. Gravani, NSW Food Authority, http://www.foodsafetymagazine.com