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Hygiene and Environmental Health Module: 7. Introduction to the Principles of Food Hygiene and Safety

Study Session 7  Introduction to the Principles of Food Hygiene and Safety


Food hygiene and safety usually refer to contamination with ‘microorganisms’ or ‘microbes’; whereas in communicable diseases, the term ‘infectious agents’ is preferred.

All over the world people are seriously affected every day by diseases that are caused by consuming unhygienic and unsafe food. We have to give due emphasis to good hygienic practices to prevent and control foodborne diseases. Foodborne diseases result from eating foods that contain infectious or toxic substances. The food we eat should be free from contaminants such as microorganisms and chemicals. This session will introduce the principles of food hygiene and safety. You will also learn about food control, food inspection and supportive enforcement measures that can contribute to food hygiene and safety.

Learning Outcomes for Study Session 7

When you have studied this session, you should be able to:

7.1  Define and use correctly all of the key words printed in bold. (SAQs 7.1 and 7.4)

7.2  Describe the public health importance and objectives of food hygiene. (SAQ 7.2)

7.3  Describe the essential functions of food. (SAQ 7.3)

7.4  Outline the principle aspects of a food control system and explain why food control is important. (SAQ 7.4)

7.1  Important principles in food hygiene and safety

In previous sessions of this Module, you have been introduced to the concept of hygiene, which was defined as the set of practices associated with the preservation of health. One important aspect of this is food hygiene, which refers to the many practices needed to safeguard the quality of food from production to consumption. This is sometimes referred to as ‘from farm to fork’ or ‘from farm to table’, because it includes every stage in the process from growing on the farm, through storage and distribution, to finally eating the food. It also includes the collection and disposal of food wastes. Throughout this chain of events there are many points where, directly or indirectly, knowingly or unknowingly, unwanted chemicals and microorganisms may contaminate the food.

The term ‘food hygiene’ refers particularly to the practices that prevent microbial contamination of food at all points along the chain from farm to table. Food safety is a closely related but broader concept that means food is free from all possible contaminants and hazards. In practice both terms may be used interchangeably.

Food hygiene is vital for creating and maintaining hygienic and healthy conditions for the production and consumption of the food that we eat.

A traditional way of eating food at the household level in Ethiopia, injera with wot (sauce), is shown in Figure 7.1. Usually this type of meal is safe because it is food that is prepared to eat immediately.

Traditional way of eating at home
Figure 7.1  Traditional way of eating at home.

The overall purpose of food hygiene is to prepare and provide safe food and consequently contribute to a healthy and productive society.

Within this overall aim, the specific objectives for food hygiene are to:

  • Prevent food spoilage, i.e. changes that make food unfit for consumption due to microbial or chemical contamination.
  • Inform and educate people about simple and practical methods of keeping food safe to protect themselves against foodborne diseases.
  • Protect food from adulteration (intentional contamination).
  • Ensure proper practice in the food trade to prevent the sale of food that is offensive or defective in value and quality.

7.2  The use and function of food

7.2.1  What is food?

Food consists of edible materials such as meat, bread and vegetables; it may be raw (like fresh fruit, Figure 7.2) or cooked, processed or semi-processed. Food is a nutritious substance eaten by us to maintain our vital life processes. It is a fundamental need, a basic right and a prerequisite to good health.

Fresh fruit
Figure 7.2  Fresh fruit. (Photo: Basiro Davey)

Food can be described in a number of different ways. Here are some terms you will find useful:

  • Perishable food: food items that have a short storage life and will become spoiled or contaminated if not preserved and handled properly, e.g. meat, eggs, milk, fruits, vegetables and the like.
  • Non-perishable food: foods which are not easily spoiled or contaminated, e.g. sugar and cereals.
  • Wholesome food: food which is sound, clean and free from harmful ingredients – it is suitable for human consumption.
  • Food hazard: food that is contaminated with biological, chemical or physical agents and, if eaten, will cause ill health.

The Nutrition Module covers all the food groups in detail and how they are used by the body.

Food is essential for the existence of all living things. Our bodies need food for energy production, to survive and to remain strong. For good health you need a balanced diet; this means that you don’t just eat one foodstuff, but you eat a range of foods so that you can get everything your body needs. The health of children will be improved and they will grow taller if they are given a healthy, balanced diet rich in protein, energy and vitamins.

Foodstuffs are of two main kinds: organic (carbohydrate, proteins, fats) and inorganic (water, various mineral elements and vitamins). The organic components are sources of energy for growth, cell multiplication, tissue repair, work and maintaining the vital processes of life. The inorganic components are believed to facilitate the physiological functions of the body, such as the regulation of blood circulation and the nervous system.

As well as being nutritious and balanced (Figure 7.3), to fulfil our needs food should also be palatable (which means tasty and good to eat) and culturally and psychologically acceptable. We should want to eat the food and have no cultural and social difficulties in eating it. Importantly, food should not contain harmful substances which are a risk to the health and wellbeing of the consumer.

Fresh vegetables
Figure 7.3  Vegetables are nutritious and healthy foods.
Food for energy, growth and development

Food is needed to provide energy for movement, work and maintaining vital functions of the body, e.g. the heart needs energy to circulate blood in our body. Food is needed to repair and replace our body cells.

Social function of food

Food has always served an important function in the social interactions between people. In Ethiopia many social occasions are centred around food. During the many holidays, families prepare particular foods and drinks to celebrate the occasion. Food is also served at social events such as weddings and funerals. On all of these occasions, food indirectly serves as an instrument to develop social bonds and relationships.

Psychological function of food

In addition to nourishing the body and filling a need in our social life, food satisfies certain emotional needs. People who travel to or live in a new land often find adjusting to the unfamiliar food and food customs a serious problem; they feel anguish and a longing for their customary food. Food can also be used to express feelings for example, the giving of food is a sign of friendship. Serving favourite foods is an expression of special attention and recognition, and the withholding of wanted foods can be a means of punishment.

Whatever the occasion or purpose for serving and eating food, special attention must be paid to its handling at all stages to attain a good sanitary quality, otherwise it could turn out to be a source of illness and dissatisfaction.

7.2.2  Food that is not safe to eat

Although food is essential for life and good health, there are some foods that are not safe to eat.

Food must be labelled correctly. When any label, writing or other printed or graphic matter on a food container is false or misleading this is known as misbranding. Misbranding violates food safety regulations and is unlawful. Food labelling should include the following facts about the food:

  • character (type of food)
  • origin (country)
  • constituents (what is in the food)
  • amount in the container
  • date of production and expiry date (this is the date when the food is no longer safe to eat).

Food labelling is very important and a sensitive area for the food trade. The quality and safety of imported, as well as exported, food depends on honest labelling. For example, if the food item has a mislabelled (false) expiry and production date, this can be dangerous for the consumer. In this way misbranding of canned meat products and other perishable food items can cause serious foodborne diseases.

Adulteration is when the normal content of the food has been intentionally changed by adding something to it that is not essential; for example, diluting milk with water and selling it as whole milk. Adulterated food could be unsafe for a number of reasons. These include poor nutrition; watered-down milk is not as nutritious as whole milk. Unsafe ingredients may have been used, for example unclean water or other harmful ingredients might have been added.

Contamination is the undesired presence of harmful microorganisms or substances in food. Food can be contaminated by unhygienic practices in storage, handling and preparation, and may compromise food safety and palatability. (Food contamination is discussed in more detail in Study Session 8.)

The term potentially hazardous food is sometimes used to describe perishable foods because they are capable of supporting the rapid growth of microorganisms. If microorganisms are allowed to multiply, this will have the potential to cause disease if the food is eaten.

7.3  Principles of safe food preparation

  • Why is it important to eat safe food?

  • If we eat safe food our health will be protected, we are less likely to get sick and we are more likely to stay healthy and productive.

You need to be able to advise people in your community about the correct methods of food handling and preparation to ensure that food is safe to eat. The key principles for safe food preparation are outlined below.

  • Choose foods that are not easily damaged by transportation, accidents or by storage.
  • Cook foods thoroughly, especially meat (Figure 7.4) because this can help to kill any microorganisms that might be present in the food.
    Butchering meat
    Figure 7.4  Meat is a healthy and nutritious food but it can become unsafe if it is not handled properly. (Photo: Zegeye Hailemariam)
  • Eat cooked foods immediately after they are cooked, rather than leave them out and eat later. Delays in eating cooked food can lead to the growth and reproduction of microorganisms in the cooked foodstuff.
  • Store cooked food carefully at an appropriate temperature. It should either be kept cold, ideally in a refrigerator, or it should be kept hot.
  • If food must be reheated, be sure to reheat it thoroughly.
  • Avoid contact between raw and cooked food.
  • Wash hands properly before handling food and before eating.
  • Keep all kitchen surfaces and utensils meticulously clean.
  • Protect food from animals including insects, rodents and other animals.
  • Use safe water in food preparation and for washing fruits and vegetables to be eaten raw (Figure 7.5).
Leafy vegetables
Figure 7.5  Leafy vegetables must be washed thoroughly with clean water before being eaten. (Photo: Pam Furniss)

These principles will be described in more detail in Study Session 10.

7.4  Food control

Food control is the regulation of the food supply industry and enforcement of food laws by national or local authorities. Its purpose is to provide consumer protection and ensure that all foods during production, handling, storage, processing and distribution are safe, wholesome and fit for human consumption. A food control system ensures that foods conform to safety and quality requirements and are honestly and accurately labelled, as required by law.

The scope of food control includes:

  • a.Food safety, which refers to all those hazards that may make food unhealthy for the consumer.
  • b.Food quality standards, which includes all other attributes that influence a product’s value to the consumer, e.g. composition, labelling, etc.

Food control covers all stages of production, processing and distribution of food. It covers controls on food that is produced or imported for consumption within the region and food that is exported outside the country.

The principal objective of the national food control system is the protection of public health by protecting consumers from unsafe, unwholesome, mislabelled or adulterated food. It also contributes to economic development by maintaining consumer confidence and providing sound regulatory controls for domestic and international trade in food.

7.4.1  Important principles in food control

There are several important principles for any food control system. We will consider four key aspects: the integrated farm-to-table concept, preventive approaches, risk analysis and transparency.

Integrated farm-to-table concept

The integrated farm-to-table concept refers to safety and quality built into food products from production through to consumption. Food control systems should address all stages of the food supply chain, including imported food. Consumers should expect protection from all hazards at all stages of the chain, i.e. ‘the farm-to-table’ continuum. This calls for a comprehensive and integrated approach in which the producer, processor, transporter, distributor, vendor, regulator and consumer all play a vital role in ensuring food safety and quality.

Preventive measures

It is much better to prevent food hazards arising than it is to simply monitor food at the point of sale or consumption. Sampling and analysing the final product will not provide adequate protection to the consumer. The introduction of preventive measures at all stages of the food production and distribution chain, rather than only inspection and rejection at the final stage, also makes better economic sense, because unsuitable products can be identified earlier along the chain.

An important assessment tool used in the food industry is the Hazard Analysis Critical Control Point system (HACCP). HACCP can be applied at all stages in the production, processing and handling of food products. It is a preventive measure designed to provide a systematic structure to the identification and control of foodborne hazards. Governments should recognise the application of a HACCP approach by the food industry as a fundamental tool for improving the safety of food.

Risk analysis

Food control requires the analysis of risks associated with unsafe food. There are three main components of risk analysis in food safety, namely risk assessment, risk management and risk communication. At the risk assessment stage, food hazards and risks are identified and described. Risk management means weighing up the alternatives and selecting appropriate options for prevention and control of food hazards. Risk communication is the stage in which information about the risks and hazards is shared among all people involved.


Consumers need to have confidence in the safety and quality of their food and this depends, in part, on their perception of the integrity and effectiveness of food control activities. All decision making processes within the food control system should be transparent. This means that all stakeholders (that is all people who have an interest in food and food control) should be able to find out how and why decisions were taken. They should also be able to make effective contributions to the process themselves. Decisions must be explained, i.e. risk communication, so that people understand why a decision is important. In this way, consumer confidence can be kept high.

7.4.2  Components of a food control system

The main components of a national food control system are:

  • food law and regulations
  • food control management
  • inspection services
  • laboratory services for food monitoring and epidemiological data
  • information, education, communication and training.

To be effective, food law and regulations should be relevant, enforceable and ‘proactive’ (that is, have a preventive component) so that they can provide a high level of health protection. They must also include clear definitions to increase consistency and legal security.

There needs to be monitoring of compliance with food laws. Quantitative monitoring includes counting the number of food premises inspected, the number of food samples taken, the number of food complaints dealt with and the number of food poisoning cases dealt with.

Government regulators are responsible for auditing the performance of the food system through monitoring, surveillance and enforcing legal and regulatory requirements. The more economic and effective strategy is to entrust food producers and operators with primary responsibility for food safety and quality. An important aspect of education is to promote voluntary compliance with food regulations. Voluntary compliance means that food producers and providers adhere to the food laws voluntarily, because they understand the benefits of good practice, rather than be prosecuted or penalised for breaching the regulations.

7.4.3  Responsibility for food control

In Ethiopia, national food control is shared between different agencies and ministries including the Ministry of Health, Ministry of Agriculture, and the Quality and Standards Authority. Their roles and responsibilities are quite different and there may possibly be duplication of regulatory activity, fragmented surveillance and lack of coordination.

There is also considerable variation in expertise and resource between the different agencies, and a conflict between the need to protect public health and obligations to facilitate trade or develop an industry or business sector. You need to be aware of these potential difficulties with the food control system.

7.5  Communication and education

Your principal role in food control is to communicate with your community and educate people about food hygiene. You may also have responsibility for inspection of food and drink service establishments – this is described in Study Session 11.

  • Why are food control and food inspection important for your community?

  • Because maintaining food safety will protect the people from harmful and dangerous foods that could make them ill.

Effective food control must combine training, education and community outreach programmes with the effective enforcement of legal requirements.

Summary of Study Session 7

In Study Session 7, you have learned that:

  1. Food is any nutritious substance eaten to maintain vital life processes. Food is important for human beings and affects human physiological activity, growth, repair and energy, and psychological and social relations.
  2. Food hygiene and safety issues are not separate from human health concerns or from community health issues. Good food hygiene practices can protect the community from foodborne illness.
  3. Different food safety terminologies like food hygiene, wholesomeness of food, food contamination and misbranding are important for understanding food safety issues.
  4. Categories of unsafe food include misbranded food, adulterated food, unwholesome food and contaminated food.
  5. Important principles for safe food preparation include having clean hands, clean surfaces, adequate cooking time and the correct conditions for food storage, among others.
  6. Producing safe food must be considered as a continuum and attention needs to be given to the safety of food from ‘farm to fork’ or ‘farm to table’.
  7. Food laws and regulations are designed to provide a high level of protection against food contamination.
  8. The objective of a food control system is to regulate the food supply industry and enforce food laws.

Self-Assessment Questions (SAQs) for Study Session 7

Now that you have completed this study session, you can assess how well you have achieved its Learning Outcomes by answering these questions. Write your answers in your Study Diary and discuss them with your Tutor at the next Study Support Meeting. You can check your answers with the Notes on the Self-Assessment Questions at the end of this Module.

SAQ 7.1 (tests Learning Outcome 7.1)

What category of unsafe food is applicable to each of the following?

  • Pineapple juice that has been diluted with water from an unprotected source.
  • A packet of tea that contains grains of sand as well as tea leaves.
  • A packet of tea labelled 100g but actually only contains 70g of tea.
  • Tilapia that were caught the day before yesterday and not kept cool or covered.
  • Cooking oil that is sold in a plastic bottle that previously contained engine oil.
  • The diluted pineapple juice is potentially contaminated.
  • The packet of tea with sand has been adulterated if the sand was added deliberately, or it could just be contaminated.
  • The 100g packet of tea that only contained 70g was misbranded.
  • The tilapia are potentially hazardous.
  • The cooking oil is probably contaminated.

SAQ 7.2 (tests Learning Outcome 7.2)

What is the principal objective of food hygiene and why is it important for public health?


Food hygiene means adopting practices and behaviours that protect food from being unsafe to eat. This is a very important aspect of public health because many diseases can be transmitted to humans via food that is unsafe.

SAQ 7.3 (tests Learning Outcome 7.3)

Outline three reasons why food is important to people. Which do you think is the most important reason and why?


Food is essential to maintain all life processes, i.e. for growth, tissue repair and all other physiological functions of the body. It also serves a social function in families and communities. Thirdly it can have an effect on the emotional feeling and psychological condition of an individual.

The first reason has to be the most important because we would die without food.

SAQ 7.4 (tests Learning Outcomes 7.1 and 7.4)

Why is it important to adopt a ‘farm to table’ approach to food control?


Food control is the system that regulates the food industry by checking that food laws and regulations are followed. It is important to cover all stages in the food supply chain, from the producers on the farm, through all stages of processing and transport to the consumer where the food is eaten. This is important because food hazards may arise at any stage and, by monitoring the whole supply chain, preventive measures can be put in place at the appropriate point.