How to protect food from contamination after it is cooked

To safely prepare food, you should follow these tips:

Table of Contents Show

Safe food storage and display
Cross-contamination
Temperature danger zone
Cold food storage
Hot food preparation and display
Cooling food
Thawing frozen food
Food serving and labelling
1. Wash your hands well after handling raw meat or poultry
2. Handle raw meat packaging just as carefully as the meat itself
3. Don't assume that your work surfaces are bacteria free, just because they look clean
4. Wash your kitchen utensils after each use
5. Don't use dishcloths for more than two days in a row

keep raw foods and ready-to-eat foods separate to avoid cross-contamination
use separate, clean utensils and cutting boards for raw foods and ready-to-eat foods, or wash and sanitise utensils and cutting boards between uses
thoroughly clean, sanitise and dry cutting boards, knives, pans, plates, containers and other utensils after using them
thoroughly rinse all fruit and vegetables in clean water to remove soil, bacteria, insects and chemicals
make sure food is thoroughly cooked and the centre of the cooked food has reached 75 °C
avoid leaving recently cooked food out to cool for more than 1 hour; as soon as food has cooled, place it in the refrigerator
know about and avoid the temperature danger zone - Bacteria grow quickly in high-risk foods that are kept at temperatures between 5 °C and 60 °C.
thaw frozen food on the bottom shelf of the refrigerator to keep it out of the temperature danger zone
take extra care when preparing foods that contain raw eggs – such as egg nog, homemade mayonnaise and aioli – because bacteria on the egg shells can contaminate the food
be trained in safe food handling and preparation.

Safe food storage and display

To safely store and display food, you should follow these tips:

keep raw foods and ready-to-eat foods separate, to avoid cross-contamination
store food in clean, food-grade storage containers
don’t store food in opened cans
make sure food storage containers have not been used to store things other than food, and wash and sanitise them before use
don’t reuse containers that are only meant to be used once
if a reusable container is in poor condition, throw it out
cover food with tight-fitting lids, foil or plastic film, to protect the food from dust, insects and cross-contamination
wash and rinse any garnishes used on food
store food in areas specially designed for food storage, such as refrigerators, coolrooms, pantries and food storerooms
never store food on the floor or on pallets, or in areas containing chemicals, cleaning equipment, clothing or personal belongings
remove and avoid using foods that are past their use-by dates, spoilt, or are in damaged containers or packaging
know about and avoid the temperature danger zone - Bacteria grow quickly in high-risk foods that are kept at temperatures between 5 °C and 60 °C.
be trained in safe food handling and preparation.

Cross-contamination

Raw food must be kept separate from cooked and ready-to-eat food. Raw food may contain bacteria, which causes food poisoning.

Cross-contamination happens when cooked or ready-to-eat food contacts raw food. Raw food should always be stored below ready-to-eat or cooked food in refrigerators and display cabinets. This way, juices from the raw food cannot drip onto cooked food.

Cross-contamination can also happen if you use dirty knives, chopping boards or other equipment. If possible, don’t use the same equipment when preparing raw food, and cooked and ready-to-eat food. Thoroughly clean and sanitise equipment after each use.

Bacteria can be transferred to food from your hands. Thoroughly wash and dry your hands before handling food, and between handling raw food and cooked or ready-to-eat food. Also use clean, sanitised utensils (tongs, spoons, spatulas) to handle cooked or ready-to-eat food.

Gloves

Disposable gloves can help prevent cross-contamination. The same precautions should be taken when handling raw food, and cooked or ready-to-eat foods. Wash and dry your hands thoroughly before putting on gloves, and always use fresh gloves.

Change your gloves:

at least once every hour
if they become contaminated
if they tear
when switching between handling raw and ready-to-eat foods
when changing tasks
after taking the rubbish out
after sweeping, mopping and cleaning.

Temperature danger zone

The temperature danger zone is between 5 °C and 60 °C. Bacteria grow quickly in high-risk foods that are kept in this temperature range.

Cold food storage

You need to keep cold foods at 5 °C or colder, and keep frozen foods frozen solid during storage at –15 °C or colder. Cool rooms, refrigerators and freezers must have proper thermometers, and temperatures should be checked regularly.

Hot food preparation and display

Hot food must be kept at 60 °C or hotter. Bains-marie and other hot food holders are designed to keep food at this temperature.

Do not use bains-marie and similar equipment to heat food. If this equipment is used for heating food, the food will spend too long in the temperature danger zone.

Before placing food in the bain-marie, make sure the food is thoroughly cooked. Ensure that the centre of the cooked food has reached 75 °C. Most bacteria are killed when food is cooked properly.

Some tips for safely using bains-marie include:

preheat bains-marie before use and operate them on the highest temperature setting
make sure the temperature of the food does not fall below 60 °C
use a clean thermometer to check the temperature of the food
do not overfill bain-marie trays, because the temperature of the food could fall below 60 °C.

Cooling food

Food that has been cooked should not be left out to cool for more than 1 hour. As soon as food has cooled, place it in the refrigerator or freezer.

Note that large portions of food cool faster if divided into smaller portions.

Thawing frozen food

Be sure to keep frozen food frozen solid while it is in the freezer.

Thaw food thoroughly before cooking. Bacteria can grow in frozen food while it is thawing, so keep frozen food out of the temperature danger zone. To do this, thaw frozen food on the bottom shelf of the refrigerator (so the juices do not drip onto other foods) and keep it in the fridge until it is ready to be cooked.

If using a microwave oven to thaw food, cook it immediately after defrosting.

If you have to cook food that is still frozen, make sure that the food is cooked right through, and that its core temperature reaches 75 °C.

Do not refreeze food that has been frozen and thawed already. Freezing does not kill bacteria, and live bacteria are still in food when it is thawed again.

Food serving and labelling

Store food in clean, food-grade storage containers that are strong enough for the food they contain. If containers are reusable, wash and sanitise them before using them. Do not reuse containers that are only meant to be used once.

Food labels or tags can carry bacteria. For cooked and ready-to-eat food, use tags or labels on the trays or containers, and not on the food itself. Be sure not to pierce cooked or ready-to-eat food with tags or labels.

When serving food, make sure that all cutlery and crockery is clean and undamaged.

Cross contamination is when harmful bacteria are accidentally transferred from raw food to ready-to-eat food.

Most cases of food poisoning are caused by bacteria from raw food coming into contact with food that is ready to eat. Follow these five rules to prevent it happening in your kitchen.

1. Wash your hands well after handling raw meat or poultry

Research done by safefood has turned up some startling evidence with regard to handwashing:

80% of people didn't wash their hands thoroughly after handling raw mince
84% didn't thoroughly wash their hands after handling raw chicken while preparing a warm chicken salad
26% of people had raw meat bacteria on their hands after preparing food

Just think about where your hands have been and where and what they will touch.

2. Handle raw meat packaging just as carefully as the meat itself

Harmful bacteria such as E.coli can last on your food packaging for up to 24 hours. These bacteria can be transferred quite easily to other kitchen surfaces and also to hands and other kitchen surfaces such as worktops and press handles. Research by the Food Standards Authority of Ireland found that 13% of chicken packaging was contaminated with Campylobacter.

When you do your shopping, pack your raw meat and poultry separately from your ready-to-eat foods. If you use reusable bags, keep one bag for raw meats only.
Store your raw meat and poultry on the bottom shelf of your fridge below ready to eat foods.
Remove your raw meat and poultry from their packaging and directly place on to your cutting board or baking tray. Wash the containers before recycling them, by rinsing them in warm soapy water. To avoid spreading bacteria around the sink, take care not to splash any water onto the surrounding areas. To prevent contaminating any of your work surfaces, it is always a good idea to sanitise the area around the sink after you wash these containers.
After you have finished preparing your raw meat or poultry, wash down all surfaces with hot soapy water.

3. Don't assume that your work surfaces are bacteria free, just because they look clean

Bacteria like Campylobacter can last on kitchen surfaces for up to 1 hour and E.coli can last for up to 24 hours. safefood research found that:

96% of kitchen surfaces were not thoroughly washed after food preparation.
43% were contaminated with raw meat bacteria after food preparation.
A further 67% of people didn't wash the chopping board after using it to prepare raw chicken.
Of the chopping boards tested, 50% were contaminated with raw meat bacteria after preparation.

It's always good practice to wash worktops and cutting boards with hot soapy water after preparing foods, especially after preparing raw meat, poultry, seafood or raw vegetables. Always clean as you go between preparing these foods and especially when handling raw foods and then handling ready to eat foods.

4. Wash your kitchen utensils after each use

The study done by safefood found that:

72% of people failed to thoroughly wash a knife that was used in preparing raw chicken before reusing it to cut salad vegetables.
67% of people failed to thoroughly wash a knife that had been used to prepare raw beef before cutting salad vegetables.
Of the knives that were tested, 18% were contaminated with Campylobacter and 5% were contaminated with E.coli.
A whopping 37% of the salads tested were contaminated with raw meat bacteria.

Scrub all kitchen utensils thoroughly in plenty of clean hot soapy water or in a dishwasher, particularly after using them to prepare raw meat or poultry.

5. Don't use dishcloths for more than two days in a row

Rinsing dishcloths under the tap does not remove germs. Dishcloths that are used for more than two days tend to have high levels of bacteria.

Food poisoning bacteria can survive and grow on dishcloths, particularly when the cloth is damp. Dishcloths are usually stored crumpled up, so they stay wet and often contain larger numbers of bacteria. Of the dishcloths tested in the safefood survey, E.coli was present on 27.5% and Listeria was present on 13.5% of them.

Change your dishcloth at least every other day.
If you use your dishcloth to wipe off 'high risk' food debris such as raw eggs, raw meat, raw poultry, raw fish or raw vegetables, change the cloth straight away.
Boiling your dishcloth for 15 minutes or washing it on a standard cycle in the washing machine are effective ways to kill any bacteria that might be present.
Don't use a dishcloth that smells.
If it looks dirty, it is very likely that a high number of bacteria are present.

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