Food Safety

Pathogens

A pathogen is a microorganism that causes disease, such as bacteria, viruses, fungi, toxins and parasites. When present in the food we serve to our guests, these pathogens can cause a range of physical symptoms, ranging from mild upset stomachs to severe illness and even death.

Common food-borne pathogens

Allergies and Intolerances

Food allergies affect many people and are caused by a person’s immune system over-reacting to particular proteins in foods. For these people, the proteins are called allergens. Symptoms can appear within minutes of a person eating a food they are allergic to, but it may take up to 4 hours for symptoms to appear. Reactions range from very mild discomfort to life-threatening and needing immediate medical attention. A severe reaction like this is called anaphylaxis. People diagnosed with a food allergy should avoid consuming all foods containing that allergen.

Common Food Allergens

In New Zealand, some of the most common allergy-causing foods include:

• peanuts
• tree nuts (like almonds and cashews)
• milk products
• eggs
• sesame
• fish and shellfish
• soy products
• wheat

Mild and Moderate Allergy Symptoms

• itching and hives
• swelling around the face
• abdominal pain
• diarrhoea
• nausea or vomiting
• sneezing

Anaphylaxis (Severe Reactions) Symptoms

• swelling of the tongue
• tightness of the throat
• wheezing and difficulty in breathing
• difficulty in talking
• dizziness
• collapse
• pale and floppy (in children)

Anaphylaxis is an extremely severe and dangerous condition which is a medical emergency and can lead to death. People who know they are at risk of anaphylaxis usually carry an adrenaline pen/injection at all times which must be administered immediately. In cases of anaphylaxis someone should immediately phone 111 for an ambulance. Anaphylactic reactions from foods are very uncommon in New Zealand but food professionals must be aware of the seriousness of the condition (HealthInfo Canterbury, n.d.).

Coeliac Disease

Coeliac disease is an autoimmune reaction to gluten, which is found in wheat and also in barley, oats and rye. It is a permanent condition which affects the lining of the small intestine, which becomes inflamed and prevents the person’s body from absorbing the nutrients in food. It is a serious condition which is estimated to affect up to 100,000 people in New Zealand. People who have Coeliac disease must avoid all products containing gluten, e.g. bread, pastry, pasta etc. Some common symptoms shown by people with Coeliac disease include:

• Tiredness, weakness and lethargy
• Weight loss
• Diarrhoea or chronic constipation
• Flatulence, cramping and bloating
• Nausea and vomiting (Paul, 2021)

Many other people suffer a reaction to gluten which is not an allergic reaction like Coeliac disease, but is an intolerance instead, although some of the symptoms may be the same. (Coolick, 2023).

Note: Coeliac disease requires a medical diagnosis through proper clinical tests.

Watch

Gluten and Coeliac Disease

An animated explanation of what Coeliac disease is and how it affects people with that condition.

Duration: 3:00

Questions

Pre-Watch Question: What kinds of foods should people with Coeliac disease avoid?

Post Watch Task: How would your diet change if you had an allergy or intolerance to gluten? Think of all the things you eat each day which contain gluten.

Food Intolerances

Food intolerances are when a person has difficulty digesting a particular food. Intolerances affect the digestive system rather than the immune system as with allergies and they are not usually as serious as allergies. People with food intolerances are usually able to eat small amounts of that food type without any problem, but this may lead to them feeling unwell. Symptoms may include:

• diarrhoea or constipation
• bloating
• flatulence
• abdominal pain
• headache
• tiredness (NHS, 2023)

Symptoms can be seen from immediately to up to 20 hours later (NZ Nutrition Foundation, 2023).

Foods can be divided into high risk, medium risk and low risk categories. Each requires different storage and handling, according to their risk level.

High-risk foods

High-risk foods (also referred to as potentially hazardous foods) are those which pose the greatest risk of containing harmful bacteria, or which have conditions in which dangerous micro-organisms can thrive. This includes foods such as:

• raw and cooked meat, poultry, fish and seafood
• dairy products
• eggs and dishes containing eggs
• soy bean and other pulses
• cooked rice and pasta
• processed vegetables

Medium-risk foods

Foods such as vegetables, fruit, bread etc. which may be kept at room temperature for a short period of time. These food items will eventually spoil, and storing in cool temperatures will extend their shelf life.

Low-risk foods

These foods are stable and can safely be stored at room temperature. They include dry-store foods such as canned, bottled and dried foods. After opening, these items should be refrigerated.

Cross-contamination is a major source of the spread of foodborne illnesses. We have already mentioned this term a few times when we looked at the different pathogens, and cross-contamination was mentioned in almost every instance.

Cross-contamination is defined as “the transfer of harmful bacteria to food from other foods, cutting boards and utensils if they are not handled properly” (US Dept of Agriculture, 2023).

Chopping boards and utensils

Cross-contamination can occur when sharing use of chopping boards, knives and other utensils between tasks involving the preparation of raw high-risk foods followed by ready-to-eat foods, for example preparing salads with the same chopping board or utensils as used to prepare raw meat, chicken, fish etc. without proper cleaning and sanitising in between.

Watch

What is cross-contamination of foods?

Video showing how cross-contamination can occur in a kitchen and the process by which it happens.

Duration: 2.14

Questions

Pre-Watch Question: Why do you think cross-contamination is such an important topic for food handlers to understand?

Post Watch Task: Note down all the ways the risk of cross-contamination can be eliminated or minimised.

A critical part of maintaining food safety is storing, preparing, cooking, cooling, reheating and serving food at a safe temperature. Food not kept at a safe temperature is said to be in the danger zone.

Danger Zone

The danger zone is the temperature range of 4ºC and 60ºC in which bacteria thrive and multiply rapidly. The fastest growth of bacteria happens around human body temperature, 37ºC.

Keeping food cold

Fresh high-risk food must be stored in the cold food temperature zone of 0º to 4ºC. Frozen foods must be kept at minus 18ºC or lower (Keeping Food at the Right Temperature, n.d.).

Correct storage of all different types of food is essential in all professional and home kitchens to ensure food safety and minimise wastage.

The FIFO principle

FIFO is a principle well-known and used in almost all areas of life where goods with a finite shelf-life are used. It stands for First in, First out and is a method of managing food items to ensure older products are used before newer ones to ensure food is not wasted by spoiling whilst in storage. It is important to ensure that when using the oldest item, that particular item is still fresh and of servable quality. FIFO applies to all kinds of food, whether it is fresh meats and vegetables or canned and bottled items. Using the FIFO principle properly will help a business to reduce wastage costs yet maintain high standards of food safety for customers.

Chilled food storage

In commercial kitchens refrigeration units are referred to as chillers. There are various different types of chiller which may be located in different areas in the kitchen.

Types of chiller in commercial kitchens

In larger kitchens there is often a walk-in chiller: a large room which is maintained at a safe food storage temperature. These usually have a set of shelving units around the sides, allowing for the safe storage of different food types and easy access for staff to get what they need. These rooms can be any size and are built individually for each business. Walk-in chillers are mostly used for storing bulk ingredients ready to be prepared, or bulk prepared foods ready to go to service. They are designed to maintain a steady, food-safe temperature of between 1ºC and 4ºC (Temperature Control, n.d.) and are not meant to be accessed frequently.

Food which is prepared and ready for service is usually placed in smaller chillers located in parts of the kitchen where they are needed. For example, trimmed and portioned cuts of meat, chicken, fish etc. will be stored in a chiller close to the cooking equipment it will be cooked on ready to serve to customers, salad ingredients will be stored in a chiller close to where the salads and garnishes are prepared etc. These chillers can be under-bench chillers (front-loading chillers under work benches) or reach-in chillers, (upright chillers similar to the domestic upright fridges).

Chilled food storage rules

1. Chilled food must be kept at a temperature between 1ºC and 4ºC.
2. Check the internal temperature of all chillers at least once a day.
3. Don’t overload chillers – all chillers should be marked with a maximum load height. This is to ensure good air flow around all the food items and reduces excessive strain on the motor.
4. Don’t put hot food straight into the chiller – follow the chilling food procedure explained in the previous section.
5. Keep chiller doors closed as much as possible – avoid unnecessary opening of doors as they will allow warm air to enter.
6. All food must be wrapped or in covered containers as a further barrier to cross-contamination
7. Follow the chiller organisation rules – these are extremely important and are a major way to minimise the risk of cross contamination.

Chiller organisation rules

Correct chiller temperature is 0-4ºC

1. Store raw and cooked foods separately. Best practice is to use separate chillers for raw high-risk foods and ready-to-eat foods if possible, but otherwise store:
   • Raw meat and poultry on the lowest shelf to prevent any drips falling onto other food items.
   • Fish on a shelf below cooked and ready-to-eat foods
   • Cooked and ready-to-eat foods on the higher shelves
2. All food must be covered or in sealed containers.
3. All food must be labelled with
   • What it is
   • When it was made or purchased
   • Who made it or prepared it
4. Chillers must be included in the regular cleaning schedule, which should include the interior surfaces, shelves, doors and handles and the motor housing unit.
5. Always use the FIFO system to organise produce in the chiller

Frozen food storage

Similar rules apply to freezers, except

• The operating temperature must be below minus 18ºC.
• You must follow safe defrosting procedures to defrost frozen items. Some food items (e.g. frozen chips and other convenience products) may be designed to be cooked straight from frozen, so always check the instructions on the packaging.
  • the recommended method for defrosting frozen meat, poultry, fish etc. is to defrost it in the chiller. This needs planning as it can take up to 24 hours to fully defrost an item, depending on the size.
  • you must place the frozen item in a container to catch any drips made as it defrosts. Frozen items will create a lot of liquid as the defrost.
  • you must follow the same safe food storage rules as your frozen items defrost – i.e. put it on the correct shelf in the chiller and keep high-risk items away from ready-to-eat foods.
  • do not leave frozen meat on the bench to defrost (WebstaurantStore, 2023).

Dry Goods

Goods such as cans, bottles, jars, dried foods and packaging etc. which are safe to store at room temperature are stored in a dry goods store room. These spaces should be:

• well-ventilated
• in a cool area
• have good lighting
• equipped with shelving so nothing is stored on the floor
• kept clean and regularly checked for signs of pests

Also, it is important that heavy items and glass items are kept on lower shelves and always use the FIFO system.

The safe preparation of food for sale begins when ingredients enter the kitchen. It is of vital importance at every stage, right until the food gets to the customer. Once food is received and stored properly in the kitchen, all kitchen staff become responsible for the safety of food being prepared and served.

• Proper personal hygiene protocols must be followed and all equipment and surfaces must be clean and sanitised before food preparation begins.
• High-risk foods must not be left in the danger zone for longer than the permitted time.
  • if you need to prepare a large quantity of a high-risk ingredient you must keep the bulk of it in a chiller and only take out what you can work on in a short period of time
• Use separate chopping boards for working on raw and cooked foods. If space permits, use different areas for preparing these different food items.
• Use the correct colour-coded chopping boards for the job

Chopping boards

The safest way to minimise the risk of cross-contamination when preparing food ingredients is to use colour-coded chopping boards. These boards are recognised in most countries as being appropriate for specific purposes. It must be remembered that just because you are using the correct colour chopping board you must sill follow the proper cleaning and sanitising processes between tasks.

Some chefs prefer to use wooden chopping boards, which is perfectly safe as long as strict cleanliness and cross-contamination procedures are used. Wooden boards cannot be cleaned in a dishwashing machine, so must be scrubbed in hot, soapy water and allowed to air-dry. Research has shown that with proper cleaning procedures wooden chopping boards actually retain fewer bacteria than plastic boards, especially if the plastic board has scratches from knives (Newshub, 2022).

Cooking

High-risk foods like meats and poultry must be cooked safely and to the required temperatures to make them safe to eat.

Watch

Food safety coaching: Cooking safely

An introduction to visual guide to safe cooking of liquids and high-risk items like burger patties and sausages.

Duration: 1:08

Questions

Pre-Watch Question: How can you tell if a burger is cooked thoroughly?

Post Watch Task: What is a visual indicator that a burger patty or sausage is cooked thoroughly?

The best way to verify the internal temperature of meat and poultry is to use a food thermometer. Poultry, pork, processed meat and minced meat should be cooked to an internal temperature of 75ºC (measured in the thickest part) to ensure bacteria are killed.

Chilling food

Cooked food which is not intended to be served immediately must be cooled as quickly as possible before putting into the chiller. You should never put hot food in the chiller immediately, as this will raise the internal temperature of the chiller and put all of the food in there at risk. Food Standards Australia New Zealand states that hot food should fall from 60ºC to 21ºC in less than 2 hours and then be reduced to 5ºC or cooler within the next four hours. This can be achieved more easily by splitting large quantities of hot cooked food into smaller quantities, then placing it in shallow containers to maximise the surface area so it cools faster.

Serving food

• Hot food must be served at a safe temperature, out of the danger zone: at least 60ºC, but 70ºC is recommended.
• Foods to be reheated must only be reheated once and should:
  • be reheated to at least 75ºC
  • be reheated rapidly
  • be served at a minimum of 60ºC

Keeping food hot

When keeping food hot to be served over a period of time (e.g. for a buffet or function) it must be kept at 60ºC or above.

Watch

Cooking, Cooling and Reheating Food

Recommended practices in safe cooking, cooling and reheating of foods which comply with HACCP principles.

Duration: 6.21

Questions

Pre-Watch Question: What is the best way to cool a large quantity of cooked soups and stews ready for storage in a chiller?

Post Watch Task: Did your understanding of rapid cooling of food change after watching the video?

New Zealand laws specify the rules for food businesses and are designed to ensure food safety. They are based on the principles of food safety we have already looked at. Food Control Plans (FCP) are a set of procedures and documentation which food businesses must use to record and verify how they handle food, keep their premises clean, train staff etc. and are checked on a regular basis by local council authorities. You can see what a FCP looks like here, and you can also download a PDF of the template.

Now it’s your turn

Take a good look at your fridge at home – is it organised in a food-safe way? Spend some time to go through the items and organise your fridge so it is a safe, clean food storage area.