Top leftover foods that can make you sick: What a microbiologist says about fridge scraps

Improperly stored leftovers can become breeding grounds for dangerous bacteria, posing a significant risk of food poisoning, according to microbiology expert Primrose Freestone. While many understand the dangers of undercooked food, the way leftovers are handled after cooking is equally critical for preventing health issues.

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Improper storage of leftover food can foster dangerous bacteria, increasing the risk of food poisoning.

Pizza, surprisingly, can be a major culprit for foodborne illness. This risk stems from various factors, including potentially undercooked ingredients, contamination from surfaces or unwashed hands, and even the herbs and spices used. Pathogens like Salmonella and Bacillus cereus can survive on dried herbs, and if cooked pizza is left at room temperature for too long, bacteria can multiply rapidly on all its components.

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Pizza cooked can cause food poisoning for several reasons: some ingredients may be raw, insufficiently cooked or spoiled, and the product may come into contact with contaminated surfaces or be handled by people who have not washed their hands.

To safely consume leftover pizza, Freestone recommends refrigerating it within two hours of delivery or preparation. Once chilled, it should be stored in a covered container and eaten within two days. Refrigeration slows bacterial growth but does not eliminate it entirely. If pizza sits out for extended periods, it can become unsafe to eat the next day, regardless of its appearance or smell.

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For the reduction of the risk of food poisoning, leftover pizza must be introduced into the refrigerator within a maximum of two hours from delivery or preparation.

Cooked chicken is another highly perishable leftover. Its high water content, nutrient richness, and low acidity create an ideal environment for bacteria that cause food poisoning to thrive. Proper cooling and storage are essential to mitigate these risks.

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Once refrigerated, the pizza must be kept in a covered container or well wrapped, to avoid contamination with microorganisms from the air, and consumed within a maximum of two days.