You can thaw and refreeze meat: five food safety myths busted

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.


Just because something passes the sniff test, doesn’t make it OK.


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.

The Conversation

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

This article was originally published on The Conversation. Read the original article.

Australians making the switch to gluten as gluten-free labelling increases

A nationwide survey conducted by the CSIRO has found that a greater number of people are making the choice to go gluten or wheat-free as consumer foods are increasingly labelled as either gluten or lactose free. 

In recent decades, the focus on ‘bad’ dietary factors has shifted to gluten: a protein found in cereal grains such as rye, barley and oats. For consumers diagnosed with a wheat allergy, the avoidance of wheat and other gluten-containing foods is essential. 

Food billed as “gluten-free” isn’t necessarily healthier. Gluten-free products can be high in calories, fat and carbohydrates, leading some people to gain weight when going gluten free. 
With coeliac disease, the body’s immune system reacts to consuming gluten by damaging the lining of the small intestine, which interferes with the body’s ability to absorb nutrients. Gluten intolerant or sensitive people experience negative reactions to gluten, but do not actually have coeliac disease. 

To add to the confusion, you can also have a wheat allergy, which is an aversion to wheat itself, so a gluten-free product may not necessarily be OK for those with a wheat allergy. With so many different causes, conditions and symptoms, diagnosis is extremely hard, and there is a lot of misinformation about gluten.

The data collected revealed that as many as 1 in 10 Australian adults, or approximately 1.8 million people, were currently avoiding or limiting their consumption of wheat-based products –with women more likely to be avoiding wheat on average than men. 

According to current Australian Dietary Guidelines, both grain and dairy based foods are an important part of a balanced diet through contributing to the daily dietary fibre and calcium intake of both adults and children.

“Our findings, plus the extraordinary rise in popularity of the gluten-free diet in Australia and elsewhere, suggest that, apart from the coeliac disease and wheat allergy, other conditions associated with the ingestion of wheat are emerging as health care concerns. Currently, the driver of most of the research activity in this area is the concept of non-coeliac gluten sensitivity (NCGS),” CSIRO said on it’s blog website.

CSIRO believes that the significant proportion of Australians undertaking restrictive diets may pose the potential danger of associated nutritional imbalances. A majority of symptomatic respondents appeared to be bypassing conventional medical advice in their decision to go wheat-free, raising the potential risk of a clinical condition going undetected. 


Good manufacturing practice key to reducing listeria risk

Between 2005 and 2014 more than 586 product recalls were initiated by Food Standards Australia New Zealand (FSANZ), with 198 due to Listeria Monocytogenes contamination, writes Bonnie Tai. 

With meat and dairy more susceptible to contracting the potentially-lethal pathogen than any other food product, FSANZ spokesman Raphael May told Food Magazine that it’s important that plant managers and staff gain a good understanding around the risks associated with Listeria. 
“Basic principles for controlling listeria in food include equipment and facilities that should be designed, constructed and laid out to ensure clean-ability, minimisation of harbourage sites and prevention of cross-contamination,” he says. 
“They should also be controlled to minimise the growth of Listeria Monocytogenes in the finished product, and to reduce the likelihood that the product will be re-contaminated or will support the growth of Listeria during subsequent distribution, marketing and home use.”

Although Listeria has been known for at least 60 years, it has only been linked to foodborne disease since the early 1980s. Since then, the pathogen has become recognised as an important food poisoning bacterium. 
While healthy individuals can become infected with Listeria, the most at-risk are the elderly, the young, pregnant women, and those with a compromised immune system. 

Despite the fact that there are a number of other pathogens that affect the food manufacturing industry, Listeria is perhaps one of the most dangerous. 
This is because the foodborne bacterium – when present in food – shows no difference in taste, smell or appearance; leading people into a false sense of security that the contaminated item is, in fact, safe to eat. 

With its unique ability to thrive and survive in even refrigerated conditions, ranging from below 1°c up to 44°c, Listeria is an organism that can fast become a lethal liability for food manufacturing industries if floor-staff are not properly educated on the dangers of an outbreak. 
So far there have only been two major recorded outbreaks of Listeriosis in Australia, reports Meat and Livestock Australia (MLA).  Once in 1990, when six stillborns, following an autopsy, were discovered to have all been infected with the same subtype of Listeria, found in a particular brand of Pate. 

The next episode occurred in 1991, after three people who ingested the same brand of smoke mussels became violently ill. An unopened packet of mussels was subsequently tested and was found to contain 107 listeria cells per gram – despite industry-dictated ‘safe’ levels sitting at less than 10 cells per gram. 
Sporadic cases still occur in Australia, with around 40 being reported per year. The numbers overseas, however, are significantly higher and the outbreaks much more severe. 

According to the MLA, 86 to 314 cases of Listeriosis were linked to the consumption of branded Mexican-style cheese in the US, resulting in a 30 per cent mortality rate among those infected. The pathogen was later traced back to the factory, and it was discovered that raw untreated milk was added to the pasteurised cheese to enhance flavour. 

As Listeria Monocytogenes is a ubiquitous organism that is found in a wide variety of environmental niches, it can be extremely difficult to eliminate from the processing environment, explained Mr May, and instead particular emphasis should be placed on minimising the risk as much as possible. 
“Data shows the rate of notifications [of Listeriosis] has remained steady over the last 10 years,” he says.
“As it is difficult to completely eliminate the risk…communications campaigns targeted at vulnerable populations, have been developed to improve awareness.”

The steps you can take to protect your plant
Microbial contamination can severely impact a food processing plant’s brand equity, authority and reputation, so it’s vital to follow FSANZ’s two-step approach to reduce the risk of Listeria spread.  
1. Environmental Monitoring 
The food processing environment should be regularly monitored and tested for L. monocytogenes or a surrogate such as Listeria spp. This is particularly important in facilities producing ready-to-eat foods that can support the growth of listeria, and should be undertaken to verify that cleaning and sanitation programs are working and there is control of niches and harbourage sites. 
Sampling and testing methods used should be sufficient to provide confidence that the environment is under control or to help clearly identify that further follow up actions are required. 
2. Process Control
Cross lot testing of finished products should be implemented to assess the performance of food safety control systems from within the plant. This helps to verify that the production and processing controls put in place are working effectively. 

To ensure that corrective actions are being implemented before microbiological criteria is exceeded; a sample schedule should be put in place as appropriate to the operations of the food business. 


Food exec gets 28-year sentence for poisoning outbreak

According to the Washington Post, former peanut company owner Stewart Parnell has been sentenced to 28 years in prison for his role in a salmonella outbreak that killed nine people and sickened hundreds between 2008 and 2009 in the US.

The sentence said the Washington Post story, “marked the most severe punishment ever for a food-related crime.” 

Parnell’s now-bankrupt company, Peanut Corp. of America, found salmonella contamination six times in its peanuts between 2007 and 2008, according to investigators.

The investigators documented a long list of unsanitary conditions at the plant, including mould, cockroaches, dirty food processing equipment, rodent activity, along with the failure to separate raw and cooked products. 

They also unearthed e-mails that showed Parnell hastily approving shipments he knew might be contaminated, according to the Washington Post.

Company supervisor Michael Parnell and Stewart Parnell’s brother also received a prison sentence of 20 years. Another employee, a quality-control manager at the plant, who was convicted of obstruction of justice, received a 5-year sentence.

“We think the sentence itself is extremely high,” said Parnell’s attorney, who also added that, “He’s obviously disappointed, but we knew it was a likelihood something like this could happen.”

Parnell will appeal the verdict, said the Washington Post story.