Where do you stand when it comes to the five-second rule?

Or maybe it's three seconds in your house.

Like many things, it's something that a quick Google search doesn't quite settle, with the internet turning up all sorts of weird and puzzling answers.

We asked two food safety experts to help set us straight on eating food that's been dropped on the floor, whether chicken should be washed before it's cooked, and when leftovers should be refrigerated.

Can we trust the five-second rule?

You might be surprised, but the five-second rule has been the subject of serious scientific investigation.

In one paper, published in 2007, scientists dropped pieces of bread and meat on tiles to measure how long it took for bacteria to transfer.

The food was measured after it was "dropped" for five seconds, 30 seconds, one minute, and even after 24 hours.

The verdict? Don't do it

So what was the result?

"We found that the amount of bacteria transferred to either kind of food didn't depend much on how long the food was in contact with the contaminated surface, whether for a few seconds or for a whole minute," one of the authors wrote.

"The overall amount of bacteria on the surface mattered more."

It's not a good idea to eat something you've dropped, no matter how quickly you pick it up. ( Pexels )

It might seem obvious, but eating food off the ground is generally a bad idea, explains Lydia Buchtmann from the Food Safety Information Council.

Pet owners should be especially careful. Fido or Puss will have brought all sorts of nasties into your house, she adds.

Next time you go to eat something that's been dropped on the ground, remember Ms Buchtmann's advice.

"It's really tempting, especially if you've dropped something that's particularly delicious … [but] if the bacteria are on the floor — and they're likely to be, if you're walking all over it — then they're going to get on the food," she says.

Should you wash your chicken before you cook it?

Julia Child was a poultry washer. ( Giphy/Julia Child )

Whether you want to roast a whole chicken, or whip up a meal with chicken pieces, many recipes call for washing the meat prior to cooking.

Some cooks, including the late great Julia Child, were all about washing the chook, but there's plenty of advice to the contrary online.

So which way should you go?

The verdict? Definitely not

For Ms Buchtmann the answer is a clear no. Raw chicken is full of all kinds of bacteria, including salmonella and campylobacter, which are "particularly nasty".

When you wash chicken, the bacteria can spread as the dirty water is splashed around the kitchen, Ms Buchtmann says.

"It's sure to contaminate the rest of your kitchen, [whether it's] your hands [or] something else you're cooking, like a salad. It's a really risky thing to do and a great way to give yourself food poisoning," she says.

Here are some other tips for preparing chicken safely from Ms Buchtmann and Clare Collins, professor of nutrition and dietetics at the University of Newcastle.

Defrost chicken in the fridge, rather than at room temperature where bacteria thrive.

Defrost chicken in the fridge, rather than at room temperature where bacteria thrive. Wash any chopping boards or knives immediately after using them to prepare raw chicken. Consider keeping a separate board for chicken and other raw meats.

Wash any chopping boards or knives immediately after using them to prepare raw chicken. Consider keeping a separate board for chicken and other raw meats. Make sure chicken is always cooked through. The meat should be a minimum of 75 degrees Celsius after cooking, Ms Buchtmann says.



That chicken you're going to roast doesn't need a bath — it's fine as it is. ( Unsplash )

Should you leave leftovers out to cool before putting them in the fridge?

When to put leftovers in the fridge often comes down to personal preference, or what you've picked up from other people.

An old housemate was my source: she told me the hot food would heat up the refrigerator and burn more energy.

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It seemed sensible, and there's plenty of people advocating for it online. But is leaving leftovers to cool at room temperature the right way to go?

The verdict? Not if you want to be safe

Bacteria happily live in environments between five degrees Celsius and 70 degrees Celsius, says Professor Collins. In other words, room temperature is pretty much heaven for bugs.

A good rule of thumb is to refrigerate food as soon as it stops steaming, she adds.

"There is a time window, usually a couple of hours, where there is a relatively low risk of food poisoning, but it's better to be on the safe side," she adds.

Your leftovers should be in the fridge as soon as they stop steaming. ( Pexels )

But what about the fridge? While hot food may have caused problems for the fridges of old, it shouldn't be a problem today, says Ms Buchtmann.

"Modern fridges and freezers can cope well with things that are quite warm," she says.

"It's really a good idea to divide your leftovers into small portions in shallow containers and cool them quickly in the fridge. As soon as they stop steaming, you can pop them into the fridge or freezer," she adds.

When it comes to food safety, don't trust the first thing you find on the internet. The Food Safety Information Council has a raft of resources with quality information, as does the Food Standards Australia and New Zealand website.

As always, a little (un)common sense will take you a long way.