Proper storage of cooked food can help households reduce waste while also lowering the risk of foodborne illnesses, nutrition experts say.

The advice comes as attention remains on reducing food loss and waste following the International Day of Awareness of Food Loss and Waste, observed on September 29.

A 2020 World Bank assessment estimated that Rwanda loses and wastes about 40 per cent of its total food production each year. The Rwanda Food Smart Country Diagnostic linked the losses to challenges across the food system, including inadequate storage and processing, spoiled harvests and household food waste.

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At household level, experts say some of that waste can be reduced by properly storing cooked food, maintaining safe temperatures and preventing contamination during preparation.

Refrigerating and reheating food

Private Kamanzi, chairman of the Rwanda Nutritionists Society (RNS), said refrigeration is one of the main ways households can preserve cooked foods such as beans, meat, rice and potatoes for later consumption.

He said food that is not consumed immediately should be refrigerated at the appropriate temperature to slow the growth of microorganisms and reduce the risk of spoilage.

Cooked food that has been refrigerated should also be thoroughly reheated before consumption, he added.

Kamanzi said bacteria such as Escherichia coli and Salmonella can contaminate meat and other foods and may cause illness if food is not properly handled, stored or reheated.

"Bacteria are normally killed by high temperatures. Proper heating helps eliminate microorganisms that may be present in the food,” he said.

He added that salting is another preservation method, particularly for raw meat, because a salty environment can help prevent the growth of some microorganisms.

However, some preservation methods are more suitable for raw than cooked food. Smoking, for example, can be used to remove moisture from raw meat and extend its shelf life.

For cooked foods such as rice, cassava and potatoes, Kamanzi said refrigeration remains one of the most practical ways of preserving them for later consumption.

Storing food at safe temperatures

Kamanzi cautioned that poor storage can expose consumers to foodborne illnesses, including diarrhoea.

He said the temperature of a refrigerator matters because food kept at an inadequate temperature may still allow harmful microorganisms to multiply.

Repeated reheating and prolonged refrigeration can also affect the quality of food, including its taste, texture and nutritional value.

According to the World Health Organization (WHO), microorganisms can multiply quickly when food is kept at room temperature.

WHO recommends refrigerating cooked and perishable food promptly, preferably below 5°C, and avoiding leaving cooked food at room temperature for more than two hours.

Food that is being kept hot before serving should remain above 60°C.

WHO also advises against storing food in the refrigerator for excessively long periods and recommends thawing frozen food in a refrigerator, cold water or microwave rather than leaving it at room temperature.

Preventing cross-contamination

Proper storage alone is not enough to keep food safe. Experts say contamination can also occur during preparation through utensils, surfaces and poor hygiene.

Hyguette Irambona, a nutritionist at Gardens for Health International, a Kigali-based nonprofit tackling malnutrition, said one common mistake is using the same chopping board for different types of food without properly washing it between uses.

"You cut fish or meat on a chopping board, then use the same board to chop salad, onions or fruits. If it isn’t cleaned properly, bacteria can transfer from one food to another,” she explained.

Knives, plates and other utensils can also transfer bacteria when they are used for different foods without being properly cleaned, particularly when meals are being prepared for many people.

Personal hygiene is equally important, Irambona said, urging people to wash their hands thoroughly before preparing or handling food.

"People come from the toilet and think they don’t need to wash their hands. The hands can transfer bacteria to food even when everything else appears clean,” she said.

The Rwanda Biomedical Centre (RBC) advises the public to wash their hands with clean water and soap before preparing and eating food, maintain personal hygiene and keep food preparation areas clean.

RBC also recommends cleaning utensils and equipment, using safe water, washing ingredients thoroughly, storing food and drinks at recommended hot or cold temperatures, preventing cross-contamination, and cooking food thoroughly.

Experts say these simple practices can help households make better use of leftovers, reduce unnecessary food waste and protect family members from foodborne illnesses.