Australians have been urged to check their fridges since news of a national butter recall affecting Woolworths, Coles and ALDI supermarket shoppers broke on January 19.
Eight varieties of Devondale and Woolworths branded butter and butter blended products, produced by Saputo Dairy Australia, have been pulled from shelves due to potential microbial contamination.
Watch the video above to find out which butter is affected
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The products have been available for sale nationally at Woolworths, Coles, ALDI, independent supermarkets and Costco.
Food Standards Australia has warned consumers to not eat any of the recalled butter products, saying they can cause illness.
At this stage, it is unknown what caused the contamination in the Devondale and Woolworths products. Consumers have been urged to seek medical assistance if they are concerned about their health.
But what is microbial contamination and what are its symptoms and health implications? Here is everything you need to know:
What is microbial contamination?
Microbial contamination is the most common cause of food poisoning in humans.
Microbial contamination relates to the presence of harmful pathogens - including microorganisms, bacteria, viruses, mould, fungi, and toxins in food.
How does microbial contamination happen?
Microbial contamination can occur in foods due to either direct or cross-contamination.
Cross-contamination is when pathogens enter food from external sources and rise to reach unsafe levels.
Direct contamination occurs when pathogens already produced or existing in the food, reaching unsafe levels.
What are the symptoms of microbial contamination?
The symptoms and severity of food poisoning vary, depending on which bacteria or virus has contaminated the food.
The most common food-borne illnesses include norovirus, salmonella, e.coli, listeria and campylobacter.
Symptoms of food poisoning can range from gastro issues - including vomiting, diarrhoea, cramps and flu-like symptoms - to serious long-term health problems like kidney failure.
Experts warn that people who are pregnant, elderly, very young, or have a compromised immune system have a greater risk of food poisoning and potential serious complications.
Consumers are urged to seek medical advice if they are in a high-risk group or are concerned about their health.
Does heating or freezing contaminated foods kill toxins?
Experts say that spoiled foods should not be cooked or eaten, even if they’ve been frozen or cooked at a high temperature.
They note that many microbial toxins are heat resistant. And while chilling foods leads the pathogens to become dormant, it does not always prevent the growth of bacteria.
