Have you ever pointed the finger at last night's dinner for an upset stomach, without thinking about what you ate earlier in the week?
Food poisoning isn’t always caused by your last meal; some bacteria play the long game!
We often think that the last meal we had is the culprit when we feel unwell, but some bacteria are quite clever and can take their time before making us sick. Many foodborne pathogens don’t show their effects straight away. Take Listeria monocytogenes for instance, a bacterium often associated with ready-to-eat meats, coleslaw-type salads, and unpasteurised dairy products. It has an incubation period that can range from 1 to 70 days! This means that symptoms like fever, muscle pain, or stomach issues can crop up long after we've consumed the contaminated food, which makes pinpointing the source quite tricky.
On the other hand, pathogens such as Salmonella and Campylobacter typically show symptoms within a window of 6 to 72 hours post-ingestion. This delay in onset can lead to confusion where people misidentify the cause of their illness, often blaming the wrong meal or even pointing fingers at the wrong place entirely, while the real source stays hidden.
This misdirection isn’t merely an academic issue; it has genuine implications for food safety systems and public health monitoring. Wrong assumptions create gaps in traceability and postpone necessary corrective measures.
Now that you are aware of this, how can you apply this knowledge to keep ‘food safe’?
If you are responsible for food safety, encourage your team to adopt a detective mindset rather than making assumptions.
Safe Practices at Home
Cook It Right
Poultry and meat should reach at least 70°C for 15 seconds to be safe to eat. Using a meat thermometer is the most reliable way to ensure the food has reached the correct temperature. If you do not have a thermometer, cook the meat until any juices run clear and piping hot.
Reheat Once
Bacteria can increase each time food is allowed to cool and is then reheated so avoid reheating leftovers multiple times.
That delicious chicken tikka in your favourite butter chicken curry might have already gone through a pre-cook/reheat in sauce, process (for quicker service times) at the restaurant before you even bought it. Therefore, it is wise not to refrigerate such takeaways for too long.
Refrigerate / Be Cautious with Ready-to-Eat Foods
Enjoy them fresh & don’t forget to wash your lettuce!
Understand “Use By” and “Best Before” Dates
“Use by/Expiry” means it is time to toss it for safety. Don’t eat after that date.
“Best before” is about quality attributes (e.g. colour, flavour, texture, and freshness)
Report Suspected Illnesses Promptly
If you suspect food poisoning, don’t hesitate to contact your local health unit. Genome sequencing is helpful for public health investigations.
Nurture Your Gut Microbiome with Probiotics
A healthy gut microbiome is vital for protecting against harmful bacteria.
Incorporate probiotic-rich foods or supplements into your diet & nourish it with prebiotic fibre.
If you have taken antibiotics, it is a good idea to restore your gut flora with fermented foods or supplements.
Remember: it is wise to consult your GP before starting any supplements if you're immunocompromised.
Transparency note: This publication is not sponsored. Food Safe upholds a professional training partnership with ZHM and Health House, reflecting our mutual dedication to GMP & ongoing food safety education.
References: MPI Fact Sheet; CDC, 2023; Cornell CALS.