Christmas and Noche Buena has just ended, but leftovers are bound to be shared in households for days to come. Experts warned that care must be taken in storing leftovers, because improper handling can lead to illness.

According to microbiologist Dr. Windell Rivera, foodborne bacteria such as Staphylococcus aureus, E. coli, and Salmonella can contaminate leftover foods.

All these bacteria are known food poisoning agents which can cause gastrointestinal diseases inducing symptoms such as vomiting, nausea, or diarrhea.

"Basta't available yung nutrients dun sa pagkain, meron silang carbon source, syempre nitrogen source sila dun sa pagkain, pwedeng dumami itong mga bakterya ito (As long as nutrients thrive in food, there is a nitrogen source within the food which can allow bacteria to thrive and multiply)," Rivera said.

Storing leftovers in the refrigerator is a good way of preventing bacteria from multiplying, experts said, as bacteria are 'disabled' under cold temperature.

However, experts warned, storing food inside the refrigerator or freezer does not mean food is totally safe.

Unclean food containers and improper kitchen practices can also be potential sources of bacterial growth, they said.

Cross contamination, the transfer of bacteria from one food or object to another, can occur whenever contaminated hands or objects make direct or indirect contact with food or containers. For instance, food handlers who do not wash their hands properly prior to handling can contaminate food with bacteria.

Kitchen cleaners, often perceived as clean, are also in fact potential cross contamination agents, experts said.

Kitchen sponges, often used and reused on several dirty plates, if not frequently cleaned, may already be contaminated by several bacteria. Constant use of a contaminated sponge can transfer bacteria to plates. If contaminated kitchenware are not cleaned and rinsed properly, they can potentially contaminate food during the next use.

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