Does the five-second rule work? Can you reheat rice? The Food Standards Agency debunk hygiene myths and provide advice on food safety.
Does the ‘five-second rule’ actually exist?
This is the myth that if you drop food and pick it up quickly enough (within five seconds is most common, although some swear by the three seconds or ten seconds!) it will still be safe to eat. Most floors will have dirt and bacteria on them which can be instantly transmitted to a dropped item of food. If food is dropped onto the floor, even for a few seconds, you should dispose of it and then clean any spillages.
Read more from the NHS on why the five-second rule is a myth.
Should you wash raw chicken?
You shouldn’t wash raw chicken or any other raw poultry or meat. There is a considerable risk of spreading bacteria around food preparation areas and onto you. Cooking thoroughly will ensure any bacteria present will be killed.
Read the NHS's guidance on why you should never wash raw chicken.
Can you tell from the look or smell of food whether it’s safe to eat?
If food smells off that is a good indication that it may be unsafe or unfit to eat, but food can have normal odours or look fine and still be unsafe. If it concerns food with a use-by date, it will only be safe to eat if it has been stored appropriately in accordance to the on-pack instructions and it is within the use-by date. This is the only reliable method. If in any doubt the food should be disposed of.
Read more about the science behind how manufacturers set use-by dates and the FSA's top tips for reducing food waste by using, cooking and freezing perishable food.
Can you reheat rice?
Ideally, rice should be eaten on the day it's cooked. If there's leftover rice, it should be cooled quickly (within one hour) and refrigerated, not left to stand around at room temperature. This is because some spores of bacillus cereus may remain in the rice after cooking and turn into bacteria. If the cooked rice is kept at room temperature, these bacteria will multiply and produce a toxin. A good tip is to place the container of rice in cold water to cool down quickly. After a short period of time, the rice can then be put into a covered container and placed in the fridge. The rice should then be reheated thoroughly within 24 hours - no later - and fully consumed. Do not reheat rice for a second time. Any remaining leftovers must be disposed of.
Extra care should be taken with takeaway rice. Ideally takeaway rice should be eaten shortly after purchase or shortly after it has been delivered. Some food establishments may pre-cook their rice and then re-heat it before it’s given to customers in the shop or delivered. Whether it's safe to reheat the cooked rice will depend on how it was stored, handled and if it was cooked outright in the first place. It’s always worth asking the takeaway business how they handle the rice, and paying particular attention to food hygiene ratings.
Read more from the NHS on why leaving rice at room temperature before reheating can cause food poisoning.
Can you eat pink pork?
All pork, including joints, shouldn’t be eaten rare and should be cooked thoroughly to ensure no pink meat remains.
Can you refreeze food that has fully defrosted?
You can refreeze almost all food after it has been fully thawed in the fridge, as long as it has been properly cooked first. For raw meat and poultry, it's advisable to cook these once they've been fully defrosted. They can be then be refrozen in their cooked state if necessary.
Read more from the NHS on how to safely store food and leftovers.
Can you eat raw beansprouts?
It's really important to check the packaging as this will confirm whether the raw beansprouts are ‘ready-to-eat’. Producers would have taken the necessary steps to ensure they're safe for consumption. If not, wash and cook them thoroughly to ensure they're safe to eat.
Read the NHS's sprouted seeds safety advice.
Do hot dishwasher cycles sterilise chopping boards, bottles & jars?
Commercial dishwashers reach temperatures of around 95°C. Domestic dishwashers can vary in efficiency and may be less reliable. However, if the dishwasher is well maintained, they should remove the majority of bugs, which will go down the drain to be dealt with at the sewerage plant. For this to work we would suggest that you don’t put heavily soiled plates into the dishwasher as this could affect its efficiency; it's best to pre-rinse to get the worst off.
Can you eat raw fish, and does it need to be ‘sushi grade’?
Some fish contains parasites that may be a risk to the health of the consumer so fishery products intended to be consumed raw (and which have not otherwise undergone a process such as marination that would kill those parasites) must undergo a freezing treatment in order to kill those parasites.
Lots of the sushi sold in shops is not made at the shop. This type of sushi should be fine to eat, because if a shop or restaurant buys in ready-made sushi, the raw fish used to make it will have been subject to an appropriate freezing treatment.
However, if you make your own sushi at home, freeze the fish at -15C or colder for at least four days before using it.
Read more from the NHS and FSA on how to prepare raw fish safely.
Which food safety myths surprised you? Are there any that we've missed off the list? Let us know in the comments below...
This article was published on 14th December 2016 and was written by the Food Standards Agency (FSA) - find out more about the FSA through their website.
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