Watch out for fuzzy food and discoloured bread - with recent high humidity, mould and fungi could be forming in your pantry right now.
University of the Sunshine Coast microbiologist Dr Ipek Kurtböke says it’s not just gross, it can result in health issues such as a runny nose, skin and eye irritation, and difficulty breathing.
“Moulds are forms of fungi that form spores to reproduce, and these spores freely detach from their body at the slightest disturbance and float in the air like dust,” Dr Kurtböke said.
She said increased humidity favours fungal growth, impacting the shelf-life of produce and how quickly it can become unsafe to eat.
“Asthma attacks can be triggered in patients when they inhale fungal spores caused by mould. Mould infections can happen in the lungs, and particularly affect immunocompromised people.
"We have to be extra careful in Queensland due to the subtropical and tropical climate, and even more so during wet and muggy conditions."
Dr Kurtböke, who has more than 40 years of research history in biodiscovery and is a member of the Australian Society of Microbiology, says people aren’t taking the dangers of mould seriously enough.
“We need to take it seriously,” she said.
“There are many different types of fungal toxins. Mycotoxins, which are produced specifically by mould, may cause fatal poisoning and toxic effects, with effects ranging from nausea, vomiting, diarrhea or acute poisoning, to immune deficiency and cancer in rare cases.
Mycotoxins occur in a wide a variety of foods and feeds including corn, peanuts, cottonseed, sorghum, wheat, corn, barley, coffee, cocoa and tree nuts (pecan, almond, pistachio, hazelnut, walnut and Brazil nut). They have also been found in rice, beer and wine.
“Fungi that produce these toxins often do so only under specific conditions of warmth, moisture and humidity,” Dr Kurtböke said.
Mycotoxins are resistant to destruction and can survive the heating process designed to kill moulds.
“That is why we need to be thinking about everything we consume, and the environment we live in and treat microbes as a potential threat.”
Fungus (mould) is also a microbe, alongside viruses, bacteria, archaea and protists.
“We shouldn’t underestimate the power of microbes to destroy something. They can colonise anything, some can break down a tree trunk – they are that powerful. In European cathedrals, marble has been eaten away by microbes,” she said.
“However, there are a number of foods that act as anti-fungals and naturally help your body combat mould.
Garlic is one of these, as it contains allicin, considered a natural antibiotic. Other helpful anti-fungals include onions, fish, green vegetables, soy products, shallots and leeks.”
Dr Kurtböke shares tips to avoid mould:
Check your pantry items during and after humid weather. Grains, rice and nuts can be a haven for mould. As soon as you see the growth – whether it’s blue, black or another colour that it shouldn’t be, it’s better to throw it out. The major fungal flora like Aspergillus, Penicillium and Fusarium are commonly found contaminating peanuts. All these fungi can be toxin-producing, and bad for your health.
In summer, it’s best to store your bread in the fridge or a cool place. If you’re defrosting bread, don’t leave it on the benchtop or wrap it while it’s still warm. Spoilage moulds including Penicillium, Aspergillus, Cladosporium, Mucorales, Rhizopus nigricans stolonifera and Neurospora have been observed on wheat breads. Moulds can appear white and cottony, black, blue-green or even red, and can lead to digestive upsets, anaphylaxis or worsening asthma.
Potatoes have a very tough skin so it’s harder for mould to penetrate but, if it’s broken, that’s when a fungal infestation can easily start. If you see white mould caused by the fungus Sclerotinia sclerotiorum on your potatoes, it's best to throw them away. The mould can penetrate deep into the potato and produce harmful toxins that can cause illness. Mouldy potatoes can also cause respiratory problems, especially if you have a mould allergy.
Onions and other produce
Aspergillus can be found on farm produce, but often the spore threshold is not enough for alarm. However, there have been cases of onions causing a severe spore load. In these cases, Aspergillus can cause an allergic reaction, lung infection and infect other organs in healthy people.
Don’t leave cut fruit and vegetables out of the fridge. If they are left on the bench, even for a short period of time, they can get contaminated by mould, especially if there is damage to their protective skin or coat.
Soft produce (perishable)
Perishable items should be consumed quickly. Strawberries, grapes, berries, mulberries, blackberries, etc, develop fungus very quickly. Even though they are very expensive, it’s better to throw them out because the toxins can spread. Even if you remove the affected berries and wash the rest, toxins would stay. More information here.
This product is very susceptible to mould even under refrigerated conditions, so it is better to discard it immediately. Or, once you have opened a jar, celebrity chef Nigella Lawson recommends covering the paste with a layer of vegetable oil to avoid oxygen which fuels mould growth.
Decaying leaves, compost, plants, trees and grain crops can harbour Aspergillus mould. It’s almost unavoidable and is rarely a problem for people with healthy immune systems. However, it has been linked to fever, bloody cough, fatigue and worsening asthma. In Egyptian tombs, the sickness that led to the death of explorers, once explained as a “curse” have now been found to have been of fungal origins.
Use materials that are mould resistant. Wash walls with vinegar regularly and ventilate your rooms where possible. Carpets should be mould-resistant and air conditioning should be cleaned every six months because the spores in there can blow around and we breathe it in. What is known as “sick building syndrome” can get worse the longer you’re in a building.
Media enquiries: Please contact the Media Team email@example.com