This time of year, most fridges are stocked up with food and drinks to share with family and friends. Let’s not make ourselves and our guests sick by getting things wrong when preparing and serving food.

As the weather warms up, so does the environment for micro-organisms in foods, potentially allowing them to multiply faster to hazardous levels. So put the drinks on ice and keep the fridge for the food.

But what are some of those food safety myths we’ve long come to believe that aren’t actually true?

Myth 1: if you’ve defrosted frozen meat or chicken you can’t refreeze it

From a safety point of view, it is fine to refreeze defrosted meat or chicken or any frozen food as long as it was defrosted in a fridge running at 5°C or below. Some quality may be lost by defrosting then refreezing foods as the cells break down a little and the food can become slightly watery.

Another option is to cook the defrosted food and then divide into small portions and refreeze once it has stopped steaming. Steam in a closed container leads to condensation, which can result in pools of water forming. This, combined with the nutrients in the food, creates the perfect environment for microbial growth. So it’s always best to wait about 30 minutes before refrigerating or freezing hot food.

Plan ahead so food can be defrosted in the fridge, especially with large items such as a frozen turkey or roll of meat. If left on the bench, the external surface could be at room temperature and micro-organisms could be growing rapidly while the centre of the piece is still frozen!

Myth 2: Wash meat before you prepare and/or cook it

It is not a good idea to wash meats and poultry when preparing for cooking. Splashing water that might contain potentially hazardous bacteria around the kitchen can create more of a hazard if those bacteria are splashed onto ready-to-eat foods or food preparation surfaces.

It is, however, a good idea to wash fruits and vegetables before preparing and serving, especially if they’re grown near or in the ground as they may carry some dirt and therefore micro-organisms.

This applies particularly to foods that will be prepared and eaten without further cooking. Consuming foods raw that traditionally have been eaten cooked or otherwise processed to kill pathogenic micro-organisms (potentially deadly to humans) might increase the risk of food poisoning.

Fruit, salad, vegetables and other ready-to-eat foods should be prepared separately, away from raw meat, chicken, seafood and other foods that need cooking.

Myth 3: Hot food should be left out to cool completely before putting it in the fridge

It’s not OK to leave perishable food out for an extended time or overnight before putting it in the fridge.

Micro-organisms can grow rapidly in food at temperatures between 5° and 60°C. Temperature control is the simplest and most effective way of controlling the growth of bacteria. Perishable food should spend as little time as possible in the 5-60°C danger zone. If food is left in the danger zone, be aware it is potentially unsafe to eat.

Hot leftovers, and any other leftovers for that matter, should go into the fridge once they have stopped steaming to reduce condensation, within about 30 minutes.

Large portions of hot food will cool faster if broken down into smaller amounts in shallow containers. It is possible that hot food such as stews or soup left in a bulky container, say a two-litre mixing bowl (versus a shallow tray), in the fridge can take nearly 24 hours to cool to the safe zone of less than 5°C.

Myth 4: If it smells OK, then it’s OK to eat

This is definitely not always true. Spoilage bacteria, yeasts and moulds are the usual culprits for making food smell off or go slimy and these may not make you sick, although it is always advisable not to consume spoiled food.

Pathogenic bacteria can grow in food and not cause any obvious changes to the food, so the best option is to inhibit pathogen growth by refrigerating foods.

Myth 5: Oil preserves food so it can be left at room temperature

Adding oil to foods will not necessarily kill bugs lurking in your food. The opposite is true for many products in oil if anaerobic micro-organisms, such as Clostridium botulinum (botulism), are present in the food. A lack of oxygen provides perfect conditions for their growth.

Outbreaks of botulism arising from consumption of vegetables in oil – including garlic, olives, mushrooms, beans and hot peppers – have mostly been attributed to the products not being properly prepared.

Vegetables in oil can be made safely. In 1991, Australian regulations stipulated that this class of product (vegetables in oil) can be safely made if the pH (a measure of acid) is less than 4.6. Foods with a pH below 4.6 do not in general support the growth of food-poisoning bacteria including botulism.

So keep food out of the danger zone to reduce your guests’ risk of getting food poisoning this summer. Check out other food safety tips and resources from CSIRO and the Food Safety Information Council, including testing your food safety knowledge.

Cathy Moir, Team leader, Microbial and chemical sciences, Food microbiologist and food safety specialist, CSIRO

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Ex-Cyclone Alfred is bringing significant rainfall to southeast Queensland and the Northern Rivers of New South Wales. Flooding has hit Lismore, Ballina, Grafton, Brisbane and Hervey Bay, which received 150 mm of rainfall in two hours this morning.

Tragically, a 61-year-old man died after being swept away in floodwaters near Dorrigo in northern New South Wales.

More heavy rain and flash flooding is expected in the coming days as the weather system moves inland and weakens.

Climate change is making these weather events more intense and frequent. Earlier this year, far north Queensland experienced major flooding. As residents of the Northern Rivers, this latest disaster is especially tough because only three years ago we faced the catastrophic 2022 floods.

We’ve studied the impact of floods on human health and wellbeing, and found floods are linked to a range of physical and mental health effects in both the short- and long-term.

So what might you experience if you live in an area affected by these floods?

We reviewed the evidence

We recently reviewed research on the physical and mental health impacts of floods across mainland Australia. We included 69 studies in our review, published over 70 years. The majority were from the past ten years, examining the effects of floods in Queensland and NSW.

These studies suggest people can expect a range of health impacts. Immediate physical health effects of floods include drowning, falls and injuries.

Chronic diseases such as diabetes or renal disease can also worsen due to factors such as reduced access to transport, health-care services, medications and hospitals.

Exposure to contaminated floodwaters can lead to skin infections, while respiratory problems can occur due to mould and damp housing in the aftermath of floods.

Floods also create ideal conditions for mosquito borne infections such as Ross River virus and Murray Valley encephalitis, while also spreading infectious diseases including leptospirosis, a bacterial infection from contaminated soil.

There are mental health consequences too

Our review showed floods also affect mental health. The more you’re exposed to floodwaters in your home or business, the worse the mental health impacts are likely to be.

The After the Flood study examined mental health and wellbeing outcomes six months after the 2017 flood in the Northern Rivers. It found people who had floodwater in their home, yard or business, or who were displaced from their home for a more than six months, were much more likely to have probable post-traumatic stress disorder, anxiety or depression, compared to those who didn’t experience flooding or weren’t displaced.

Repeated natural disasters could compound these mental health consequences. Southeast Queensland and the Northern Rivers in NSW have experienced multiple disasters over recent years. The Northern Rivers faced major flooding in 2017, bushfires in 2020, further major floods in 2022, and now Cyclone Alfred in 2025. These repeated disasters have taken a toll on our community, creating a seemingly never-ending cycle of recovery, rebuilding and preparation for the next disaster.

Our understanding of the unique challenges faced by communities which experience multiple disasters is still growing. However, a recent Australian study showed exposure to repeated disasters has a compounding effect on people’s mental health, leading to worse mental health outcomes compared to people who experience a single disaster.

Mums and babies

The health effects of floods extend far beyond the initial emergency and beyond the infections and mental health consequences you might expect.

The Queensland Flood Study tracked pregnant women exposed to the 2011 Brisbane floods. Researchers assessed mothers’ stress related to the flood and tracked them and their children at six weeks old, six months, 16 months, 2.5 years, four and six years. It found some links between prenatal stress and developmental outcomes in children.

While the health effects after flooding are diverse, the research to date is not comprehensive. We need to learn more about how floods contribute to or exacerbate existing chronic illnesses, disability and long-term mental health issues.

The impacts are inequitable

Flooding exposes and worsens existing inequalities. Socially vulnerable groups are more likely to be exposed to flooding in their homes and have less access to resources to respond and recover from these events, putting some groups at higher risk of negative health impacts afterwards.

Some research has looked at the disproportionate impacts on people with disabilities and their carers, First Nations communities and people from disadvantaged backgrounds.

After the 2017 Northern Rivers floods, for example, people with disability and their carers were more likely than others to:

• experience disrupted access to food, support networks and essentials such as health care and social services
• continue to be distressed about the flood six months after it happened
• be at relatively high risk of post-traumatic stress disorder six months after the flood.

However, targeted flood research exploring the experiences of these vulnerable groups in Australia is limited.

Moving forward, it’s vital we examine the varied impacts of flood events for more vulnerable groups, so we can better support them in the wake of devastating events such as Cyclone Alfred.

If this article has raised issues for you, or if you’re concerned about someone you know, call Lifeline on 13 11 14.

Jodie Bailie, Senior Research Fellow, The University Centre for Rural Health and The Centre for Disability Research and Policy, University of Sydney; Jo Longman, Senior Research Fellow, The University Centre for Rural Health, University of Sydney; Rebecca McNaught, Research Fellow, Rural and Remote Health, University of Sydney, and Ross Bailie, School of Public Health, Honorary Professor, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.