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The Sniff and Smell Test

The Sniff and Smell Test

Have you ever had bananas go ripe and not know what to do with them? Or have milk past its expiration date? Most people will say they’ve had this experience.Fruits & Vegetables and Dairy Milk are in the top list of Most Wasted Foods Worldwide. And we want to provide you with a guide that may help you use your own Sniff and Smell test to prevent good food from being wasted.

Dairy Milk

Milk that does not look or smell spoiled which was refrigerated below 50°F C (10°C), should be safe to consume. Most milk in the world is pasteurised and typically pasteurised using High Temperature Short Time (HTST) pasteurisation. When milk is treated using HTST pasteurisation its temperature is raised to at least 71.66667 °C for at least 15 seconds. This heat treatment destroys many foodborne pathogens that may be present in the raw milk.

The milk is then cooled, packaged and enters the distribution chain for eventual purchase and storage in the home refrigerator.


Bananas that do not look or smell mouldy can be safely consumed. Risks of bacterial disease from bananas appear to be very low based on both CDC data (Centers for Disease Control and Prevention, 2021) as well as limited publications in the scientific literature which indicate that foodborne pathogens do not grow on the surface of peels (Behrsing et al., 2003).

It does appear that there is some risk of fungal growth and a possibility of mycotoxin production in bananas as they age (Sarkar et al., 2011).

General advice regarding the food safety of mouldy foods would apply. If a soft fruit like banana looks or smells mouldy , it should be discarded and not consumed (Coton and Dantigny, 2019).

So, before you throw out that food, let’s make sure it’s not safe for you to eat. Always, Make Taste Not Waste.

Written in partnership with Donald W. Schaffner, Ph. D. Department of Food Science at Rutgers, The State University of New Jersey

REFERENCES:Ash, C., Priest, F.G., Collins, M.D., 1993. Molecular identification of rRNA group 3 bacilli (Ash, Farrow, Wallbanks and Collins) using a PCR probe test. Antonie van Leeuwenhoek. 64, 253-260.Beattie, S.H., Williams, A.G., 1999. Detection of toxigenic strains of Bacillus cereus and other Bacillus spp. with an improved cytotoxicity assay. Letters in Applied Microbiology. 28, 221-225.Behrsing, J., Jaeger, J., Horlock, F., Kita, N., Franz, P., Premier, R., 2003. Survival of Listeria innocua, Salmonella salford and Escherichia coli on the surface of fruit with inedible skins. Postharvest Biology and Technology. 29, 249-256.

Centers for Disease Control and Prevention, 2021. National Outbreak Reporting System (NORS). (accessed July 5, 2021).Sarkar, S., Shilpa, P., Girisham, S., Reddy, S., 2011. Incidence of toxigenic fungi in rotting fruits of banana. BioTechnology: An Indian Journal. 5, 1-4.

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