Food Safety and ContaminationYear 8 Food Technology Term One

Safe Food

Food hygiene and safety is about ensuring that the food that we consume is safe to eat and does not put us at risk of food poisoning.

Food safety regulations in Australia help to ensure that food is safe up until the time that it reaches us in the kitchen- whether that is at school or home.

Once the food is with us in the kitchen it is up to

us to make sure that it is stored and prepared

in a safe way.

Cross Contamination

Cross Contamination occurs when bacteria and viruses are transferred from a contaminated surface to a surface that is not contaminated.

These bacteria and viruses can be transferred from humans, kitchen equipment, work surfaces and other foods

Everyone who handles food from the farmer to the butcher and the chef, must ensure that they follow good hygiene practices to avoid cross contamination

Types of Food Contamination

Bacteria is not the only cause of food poisoning. If we eat food that has been contaminated we can become sick. Food Can be contaminated by the following:

Chemicals

Natural Toxins

Foreign Matter

Organisms

Types of Food Contamination: Chemicals

Chemical substances such as food additives and cleaning products are safely used in the production of food. They assist farming, help preserve food and make it look and taste better. They can be used safely for cleaning and pest control.

Chemicals in the home include those used:•To clean kitchen surfaces and equipment•As pesticides

Types of Food Contamination: Chemicals

When chemicals are used inappropriately or incorrectly, food can become unsafe. Chemicals can become very harmful if they are:•Spilt on or near food•Mistaken for food or drink

The following actions will help to prevent contamination of food with chemicals•Always read the safety directions•Chemicals should not be stored near food•Chemicals should never be put in food containers or drink bottles and should always be labelled clearly.

Types of Food Contamination:Natural Toxins

Toxins are poisonous substances produced by some micro-organisms, plants and animals. Most toxins that can make us sick are tasteless and will not breakdown when we cook our food. Potatoes, nuts, mushrooms, and seafood can all contain natural toxins under certain conditions.

For example:

•When potatoes are exposed to light and turn green they produce toxins.

•Fish and other seafood can build up toxins if they feed on algae or other fish that contain toxins

Types of Food Contamination:

Foreign MatterSometimes foreign matter such as hair, jewellery, glass, dead insects and pieces of metal finds its way into food. Foreign matter such as glass and metal can physically injure someone. Risks include broken teeth, cuts to the throat and piercing of the gut.

Other foreign matter can introduce harmful micro-organisms into food, which can then result in food poisoning.

Food Contamination: Organisms

Organisms are a more common cause of food poisoning than chemicals, natural toxins and foreign matter. This is mostly due to micro-organisms (germs), though there are larger, visible organisms of concern such as some moulds or parasites.

There are many different types of micro-organisms. Most of them are so small that millions could sit on the head of a pin. Most of them are harmless to humans. Some are used to make foods such as yoghurt and bread. However others can make us very sick

The organisms that can make us sick include: Viruses, Mould, Parasites and Bacteria

Food Contamination: Organisms

• Viruses

Viruses are extremely small micro-organisms that need a living body in which they grow and multiply. They do not grow in food.

• Viruses that cause food poisoning usually live in humans. When someone has a viral illness, they can pass the illness onto others by contaminating food with the virus.

Only a small number of viruses need to be taken into the body for a person to become sick.

• This is why good personal hygiene is important when handling food. It is also one of the reasons we shouldn’t handle food when we are sick.

Food Contamination: Organisms

• Parasites:

Parasites feed off other organisms. If we eat food that is contaminated with parasites, we can become sick. Parasites can be found in the flesh of many animals. To safeguard us Australia has strict controls over all meat for sale. Thorough cooking kills parasites.

Food Contamination: Organisms

• Mould

Moulds are a type of fungus. Usually moulds can be seen and there are both good and bad moulds. Some good moulds are used to manufacture food, such as certain soft cheeses. However other moulds can make food look unattractive and spoil it. Some moulds even produce poisonous toxins. We should not eat mould, except when it is used intentionally.

Food Contamination: Organisms

• Bacteria

Bacteria are one of the main causes of food poisoning. They are also an essential part of the living environment. Most bacteria on food just make the food deteriorate. However some bacteria on food or those living in or on us can make us sick. Under the right conditions, bacteria can multiply to large numbers in our food to the point that our body cannot fight them off. Two common examples of food poisoning that can make us sick are Campylobacter and Salmonella.

Campylobacter Salmonella

The Danger Zone

The Danger Zone is the temperature at which bacteria multiply rapidly. Foods that could give us food poisoning should be kept below 4 if ℃they are be served cold or above 60℃if they are served hot

The temperature danger zone is between 4 and 60 ; it is between ℃ ℃this temperature range that bacteria can grow to unsafe levels

Low temperatures (below 4 ) prevent ℃food poisoning bacteria from multiplying to dangerous levels and high temperatures (above 60 ) will kill bacteria and viruses ℃