sanitation in food premises

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This presentation is from the course Sanitationof the FAO Good Hygiene Practices (GHP) Toolbox . Readers are encouraged to visit the online resource for a full learning experience. Sanitation in food premises

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This presentation is from the course “Sanitation” of the FAO Good

Hygiene Practices (GHP) Toolbox.

Readers are encouraged to visit the online resource for a full

learning experience.

Sanitation in food premises

Sanitation in food premises: Presentation Objectives

The objectives of the presentation are:– To provide an overview of the topic “Sanitation in food

premises” as covered in the FAO GHP Toolbox.

– To make users aware of the importance of cleaning and disinfection programmes as the basis of the production of safe, high quality foods;

– To introduce the basic theory of cleaning and disinfection so trainers can better advise their audiences on how to clean and, if necessary, disinfect premises and equipment;

– To enable trainers to develop cleaning and disinfection programmes adapted to the technical level of a specific food business;

Sanitation: Training Outline Overview

1. Understanding the importance of sanitation

2. Removing soils by cleaning

3. Eliminating microorganisms by disinfecting

4. Developing a sanitation programme

Cleaning and disinfection programmes are essential for

the production of safe food

Only the regular performance of cleaning

(and, if necessary, disinfection) programmes

will ensure that a food business produces

food that is safe and of high quality.

Cleaning operations are a key component of

any food safety system. Maintaining a food

production site at high sanitary levels

requires time, adequate financing and careful

training of personnel.

Regular cleaning can prolong the shelf life of

a product and will pay off for a business in

the long run.

Cleaning and disinfection steps have separate goals

Cleaning removes

– soils (e.g. food

and mineral

residues)

– dust

– dirt/waste

Disinfection is only

done after soils have

been removed in

order to inactivate

remaining

microorganisms!

Note that the term “sanitation” is used by different organisations/publications to

describe a number of actions such as providing clean facilities, maintaining

hygienic conditions, and procedures of disinfection.

Sanitation: Training Outline Overview

1. Understanding the importance of sanitation

2. Removing soils by cleaning

3. Eliminating microorganisms by disinfecting

4. Developing a sanitation programme

Soils have to be regularly removed

Cleaning is an essential part of any food production.

Correctly carried out, cleaning operations

– prevent the build-up of dirt and soils that stick to surfaces and

thus reduce the time necessary for each cleaning step;

– remove food and hiding spaces for pests and reduce the

bacterial load and thus improve levels of hygiene;

– protect surfaces from corrosion through soils, food and

detergent/disinfectant residues;

– prevent contamination of foods with allergens;

Start by removing gross debris

Always

– start by removing gross debris

(i.e. constant removal of used

packaging and food waste)

and then only

– tackle the “small” dirt (e.g.

cleaning sticky surfaces).

The cleaning process

starts with a dry pickup of

waste and dirt

Effectively removing soils is a challenge

Depending on which type of soil is to be removed from which type of surface a different cleaning approach is used.

Examples of types of soil a food processor will want to remove are:

– organic soils from food residues (fat-, protein-, carbohydrate-based);

– mineral soils from water deposits;

– biofilms (microbial);

– lubricating greases and oils;

– other (sands in bottles, sticky labels etc.);

Removing soils without using water

Dry cleaning methods are used for low‐moisture foods, and in particular with foods that are hygroscopic.

Examples are: Bakery goods, nuts and seeds, candy, grains, snack foods, dried foods (milk powder, etc.)

Dry cleaning essentially consists of the mechanical removal of soils using sweeping, brushing, wiping and vacuuming with the aim to minimise the spread of ‘dust’ from one area to another.

Disinfection following dry cleaning is done by applying 70% ethanol and allowing it to dry off before equipment is reassembled.

Unhygienic accumulation of

dust in a rice mill

Cleaning with water

Water alone does not remove all

soils because pure water does not

attach well to smooth surfaces due

to its surface tension.

In addition, not all soils are soluble in

water.

For this reason a number of

chemicals are used to help remove

soils from equipment, work surfaces,

and walls and floors. The natural surface

tension of water droplets

prevents the water from

loosening and effectively

removing soils.

Improving wet cleaning with the help of chemicals

There is no single chemical that effectively removes all types of soils.

The selection of suitable chemicals for cleaning requires special knowledge and therefore cleaning chemicals should be bought from specialised suppliers who provide professional support on how to use their products.

Sequestrants and

surfactants support the

action of alkali and acids to

achieve a

desired result.

Alkali and acids supply

the brute force of cleaning.

Surfactants improve the cleaning effect of water

Surfactants (often referred to as detergents) are

neutral cleaners and are used in hand washing

soaps.

The presence of surfactants enables cleaning

chemicals to reach the soil through

• wetting (reduction of surface tension);

• foaming (e.g. improved adherence to walls);

• spreading (e.g. entering small gaps);

• emulsification (e.g. making fats soluble in

water);

Sequestrants prevent the build up of mineral deposits

The quality of water (i.e. hardness, pH, impurities such as minerals etc.) influences the effect of detergents.

Sequestrants bind metals and thus can remove mineral hardness from water and make it softer for improved cleaning.

EDTA (ethylene diamine tetra acetic acid) and polyphosphates are known examples of widely used sequestrants. It should be noted that these chemicals have been overused and are now considered environmental pollutants.

Depending on the level of water hardness in a plant the use of sequestrants could be reduced if they have not been included by default in commercially available detergents.

Different soils are soluble at different pH

The pH of the cleaning compound has an effect on the

solubility of different soils:

pH 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Acid cleaners

used to remove

fresh mineral films

such as milk stone

and beer stone

Alkali/caustic cleaners

to remove proteins,

fats/oils and

carbohydrates

(carbohydrates are

usually water soluble

and easy to remove)

pH = 7,

Neutral

cleaners

used for

hand-

washing

detergents

Overview of food soils and recommended cleaners

Soil type Solubility

characteristics

Recommended

cleaning agent

Sugars, organic acids,

salts (i.e. fruit and

vegetables)

water-soluble mild alkali

Foods high in protein

(meat, poultry, fish, eggs)

alkali-soluble

(only water soluble when

denatured)

Alkali

Starchy foods (e.g.

potatoes)

Partly water-soluble,

alkali-soluble

mild alkali

Fatty foods (e.g. butter,

oil, meat fats)

alkali-soluble or soluble

in water hotter than 40°C

Mild-strong alkali

Minerals (e.g. milk stone,

protein scale, beer

stone)

Only acid soluble Acid

4 factors affect the efficiency of cleaning processes

time – cleaning

efficiency can be

improved by

increasing the

application time

temperature –

higher temperatures

lead to increased

reaction rates.

Effective cleaning

starts at 40-45°C

(melting of fat)

type of cleaner –

needs to be

selected for type of

soil and water

properties

mechanics –

increased

turbulence or force

of scrubbing

provides for more

effective removal of

soils.

Rinsing and drying are part of each cleaning process

Dry pickup of waste and dirt

Use cleaning agent to remove soils

Rinse – use potable water to remove

soil and detergent residues

Remove excess water and dry

Cleaning

Residues of cleaning chemicals can contaminate foods and therefore

careful rinsing after the use of cleaning chemicals is necessary.

Fungi can grow in water droplets and it is therefore essential to dry

equipment and surfaces after cleaning!

Wrong cleaning can irreversibly damage equipment

Physical and chemical cleaning methods

can be very abrasive and if used wrongly

irreversibly damage surfaces and

equipment.

It is therefore necessary to only use

– recommended detergent in correct

concentrations; and

– adequate cleaning equipment (careful,

scratchy sides of sponges are often too

abrasive for cleaning chrome surfaces!).

Staff must be

instructed on how to

dilute cleaning

chemicals!

!

Sanitation: Training Outline Overview

1. Understanding the importance of sanitation

2. Removing soils by cleaning

3. Eliminating microorganisms by disinfecting

4. Developing a sanitation programme

Disinfection is the step that comes after cleaning

Disinfection inactivates microorganisms only if soils have first been removed.

Two main methods of disinfection exist:– physical (e.g. heating, applying pressure, using UV); and

– chemical (e.g. chlorine, ethanol, ozone).

Disinfection in the food industry is a complex topic. This section only provides a general overview of disinfectants and illustrates their use through two examples of disinfection methods commonly used in food industry.

Remember, many viruses are resistant to disinfection methods and

disinfectant concentrations commonly used in food industry!

Evaluation of most effective method of disinfection

Often, disinfectants in use do not target the

microorganisms of concern or then are applied wrongly and

have no effect.

Deciding on the appropriate disinfectant and/or disinfection

method for a specific food production facility needs careful

evaluation.

Prior to deciding on which disinfectant to use a food

business should consult with more than one supplier and

carefully check the promises made by sales people.

The following slides provide insight into different methods

of disinfection and types of disinfectants used.

An example of a physical disinfection method

Disinfection with steam or hot water in closed production processes is widely used in food production.

Steam and/or boiling water are effective disinfectants as:

– they penetrate into corners and small spaces;

– leave no residues:

– Attack all types of microorganisms;

Careful: if water hardness exceeds 60 mg/l, water scale is deposited and needs to be removed!

Bottling lines can be effectively

disinfected with steam/hot water

The temperature of the water determines the time of exposure needed to ensure the desired reduction of microorganisms.

Two different types of chemical disinfectants are mainly

used in the food industry

Redox agents that– inactivate microorganisms

quickly

– leave no residues (are “used up”)

– are highly sensitive to dirt

Examples are chlorine releasing compounds and ozone.

Nitrogen compounds that– inactivate microorganisms slowly

– leave residues

– are less sensitive to dirt

– are preferred for use on open spaces (e.g. walls)

An example would be QACs (Quaternary Ammonium Compounds).

Depending on the targeted type of microorganism and the surface/equipment

that needs to be disinfected different types of chemical disinfection methods will

be used.

An example of a chemical disinfectant: Chlorine

Chlorine compounds are often preferred over other disinfection compounds because they:

– are fast-acting;

– kill all types of vegetative cells (not spores);

– are usually low-cost;

– do not require rinsing if the concentration is 200 ppm or less;

– are available as liquid or granules;

– are less affected by water hardness;

Chlorine is often used to disinfect

water used in food processing

The effectiveness of chemical disinfectants is influenced

by a number of factors

Concentration

– Interfering substances, primarily organic matter such as residual soil (including high microbial loads) react with disinfectant and thus reduce their concentration to ineffective levels.

– Each disinfectant has an optimal concentration at which it inactivates bacteria.

pH

– Even small changes in acidity or alkalinity can affect the activity of sanitizers

– Chlorine and iodine compounds should be used at pH values of around 7.0.

Temperature

– Chemical reactions occur more rapidly at higher temperatures.

Contact time

– Nitrogen compounds are slow-acting whereas redox agents are fast acting.

Water hardness

– Hard water makes disinfectants less effective (if the water hardness exceeds 200 ppm of calcium, a sequestering agent is necessary).

Only use approved disinfectants and never skip cleaning

step

Many chemicals inactivate microorganisms but not all are approved for use in food production premises.

Therefore, only buy from a reliable supplier!

Competent authorities can provide guidance.

NEVER skip the cleaning step!

Examples are:

– wiping knife with cloth and then disinfecting;

– not washing hands but just using disinfectant;

Sanitation: Training Outline Overview

1. Understanding the importance of sanitation

2. Removing soils by cleaning

3. Eliminating microorganisms by disinfecting

4. Developing a sanitation programme

Drawing up and managing a cleaning programme

The following key elements must be considered when

drawing up and managing a sanitation programme:

– Selection of methodology, cleaning chemicals, cleaning equipment

– Selection of suitable suppliers of chemicals

– Development of cleaning schedules

– Identifying and training of cleaning staff

– Implementation of monitoring and verification systems

– Representation of hygiene issues to management

Completing and implementing all these elements for an

entire processing plant will take time.

An idea would be to start with key areas (e.g. toilets and

production line) and tackle cleaning programmes for other

areas (e.g. offices, recreation area) at a later stage.

Organizing sanitation operations

Sanitation operations should follow a logical

sequence to prevent contamination of foods

and/or clean rooms and equipment.

A sanitation sequence determines the order in

which the product contact surfaces of equipment

and environmental surfaces (walls, floors, drains,

etc.) are cleaned and disinfected.

The sequence must be performed at a ‘room’

level so that all environmental surfaces and

equipment in the area are cleaned at the same

time.

Do not forget to dry environmental surfaces and

all equipment. Aerate rooms (with clean air!),

and dry surfaces/equipment with clean clothes.

Watch the use of

hoses as they can

spread contamination!

Developing a sanitation plan

Support the sanitation

team by developing a

detailed sanitation plan;

if necessary with

pictograms and colour

coding for the different

type of chemicals.

The sanitation plan

should include areas

under machines and

tables and other

surfaces that are

difficult to reach.

Deciding on frequency of cleaning operations

The frequency of cleaning will depend in part on the type of processing area and how often the area/equipment is used (e.g. does the production line run continuously, or is there a weekend shutdown?).

Periodic (e.g. monthly or every half a year) sanitising procedures involve

– additional equipment dismantling;

– the application of special cleaning chemicals;

– cleaning of ceilings and overhead fittings.

Implementation of cleaning operations are best

controlled through the use of cleaning checklist

A cleaning checklist allows

• the cleaning team to keep track

of their work; and

• the supervisor to monitor

effectiveness and control the

cleaning team.

Completed cleaning checklists

should be filed for a defined amount

of time – they are proof of a

businesses compliance with good

hygienic practices.

The safety of workers needs to be ensured

Cleaning operations may involve the use of aggressive chemicals, hot water and steam.

Appropriate precautions need to be taken to ensure the safety of workers.

Therefore, workers responsible for cleaning and disinfecting operations must be properly trained

– in the preparation and use of the cleaning chemicals, and

– with regard to safety requirements.

Safety precautions may include wearing of goggles, gloves, and aprons.

Clear instructions must be given to avoid any accidents caused by electrocution (e.g. power off, unplug cables, etc.).

Provide adequate cleaning equipment and storage

space

Cleaning and disinfecting operations

can only be effective if the

equipment is adequate.

Cleaning equipment should be

– of good quality

– cleaned regularly and, if necessary,

disinfected

– regularly replaced

– stored correctly (depicted is a correct

storage of cleaning equipment)

Monitoring effectiveness

There are a number of simple tests

that can be performed to monitor

effectiveness of sanitation

operations:

– Visually inspect equipment;

– Smell or taste rinsing water;

– Control the pH of water to determine if

residues of chemicals are present;

– The concentration of acid and alkali

cleaners by measuring conductivity;

– Add alkali/acid to rinsing water, if

flocculation occurs then further rinsing

is necessary;

A disassembled tube pasteurizer

that allows for control of the

effectiveness of cleaning

programmes!

Cleaning overlaps with maintenance

Equipment and machines that are in a state of disrepair are also difficult to clean. Therefore effective cleaning and disinfection relies on a solid maintenance programme;

Either have a system in place that allows for the rapid communication of necessary maintenance work to the responsible staff or empower the cleaning crew to perform simple maintenance work themselves.

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Train cleaning staff to look

behind O-rings and if

necessary, replace them.

Deciding when microbiological testing is required

Microbiological sampling can be of use to monitor the effectiveness of cleaning and disinfection programmes.

However, a careful design of microbiological monitoring programmes is necessary in order to obtain meaningful results.

Only trained personnel should be given the task of sampling because it is very easy for an untrained person to contaminate samples.

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A well implemented preventive sanitation programme is more

effective to ensure food safety and quality than extensive

microbial analysis.

Cleaning and Disinfecting: Conclusions

Cleaning and disinfection programmes are part of a sanitation system and are essential for the production of safe and high quality food.

Different soils and surfaces need a different cleaning approach and a number of chemicals are used to help remove different types of soils and to improve the cleaning efficiency of water.

Disinfection operations are used to reduce the level of microorganisms after soils have been removed. Both physical and chemical methods of disinfection are used in food industry.

Sanitation operations should be organised to prevent the contamination of foods and/or clean rooms and equipment.

A sanitation plan helps the staff responsible for cleaning carry out cleaning and disinfection steps correctly.

The effectiveness of cleaning operations must be regularly controlled.

You have reached the end of the presentation

Sanitation.

This presentation is from the course “Sanitation” of the FAO Good

Hygiene Practices (GHP) Toolbox.

Readers are encouraged to visit the online resource for a full

learning experience.