Wastage. That is the one thing no one needs to be taught about. You get it naturally that it is not okay to waste anything.

And no where does this natural trait come to full blossom than in food matters. Perhaps because we must eat to live, the reason we feel a bit guilty having to throw away leftover food. 

Of course, not everyone does that. As long as the food has not gone bad, people will eat it even if after overnight. That includes commercial eating places such as restaurants.

"When food stays overnight, I add extra spices, steam it for a few minutes and there I have another meal,” says Pierce Kayumba, a resident of Nyamirambo. "As long as the food did not go bad, I wouldn’t have any qualms; wasting food when there are millions going without a meal for days is not something I want to do.”

According to the Food and Agriculture Organisation (Fao), more than the 222 million tonnes of food are lost to leftovers annually in developed countries, a quantity that accounts for the net food production in sub-Saharan Africa. 

Further studies indicate that each person in sub-Saharan Africa loses between six and 11 kilogrammes of food per year, while a 2011 study by the Ministry of Agriculture estimated post harvest food losses at 22 per cent. 

Jeanne d’Arc Nyirajyambere, a senior nutrition specialist for the Usaid Ejo Heza programme, says reducing food wastage requires an increase in literacy education, which eventually increases knowledge on food utilisation. 

"There is a link between nutritional activities, agriculture extension and increased food production,” Nyirajyambere says.

"There are better methods of food utilisation and cooking demonstrations for healthier diets. All these activities can provide room to fully use food materials. Instead of wasting food, we can still reuse it since food wastage is a major cause of food insecurity.” 

But the Food and Drug Administration (FDA) recommends hot or cooked food to be eaten right away and not to leave it at room temperature because of microbial safety concerns. 

One of its recommendations is that cold food should be eaten within two hours of preparation or else placed in the refrigerator. There is an exclusion, however, toward the use of stuffing and gravy.  

The FDA  states that these foods should be used within two days. Although food can be reused, the FDA warns that it should not be kept in the ‘danger zone.’ 

A danger zone is a range of temperatures at which bacteria can grow. It is usually between 40° and 140° F (4° and 60° C). To keep food safe, it’s important to keep it below or above the danger zone.

The FDA recommends unused food to be discarded within four days. 

Eduardo Niyonsoba, a specialist in public health at La Leference Clinic, says every cook should know that food contains bacteria and if mishandled they cause illness since most nearly remain in our food after simple boiling.

What makes you sick

Niyonsoba says although boiling kills bacteria, it does not kill all. Besides, most bacterial spores are resistant to normal heat. 

"After cooking food, if left to cool, temperatures fall, bacterial spores germinate. On multiplication they release toxins for example clostridium botulinum releases a toxin that has negative effects on the nervous system after contracting botulism,” he says.

The World Health Organisation (WHO) also suggests that commercial pasteurisation (vacuum packed pasteurised products, hot smoked products) may not be sufficient to kill all spores and, therefore, the safety of these products must be based on preventing bacterial growth and toxin production. 

Refrigeration temperatures combined with salt content or acidic conditions will prevent the growth of the bacteria and formation of toxin.

When it comes to food poisoning, most of us know the dangers of undercooked chicken or seafood left out of the fridge for too long, but rice can also leave you with more than a full belly.

You can get food poisoning from rice if you don’t store it in the fridge after cooking

What makes you sick is bacillus cereus. These bacteria produce toxins that will give you a mild vomiting illness shortly after you eat the contaminated food.

If food is cooked and handled correctly, the bacteria isn’t a problem, but in dry conditions – such as those found in a rice packet or spice container the bacteria remains present as spores. 

The spores remain dormant until you add water, then they germinate and grow.

Niyonsaba says as long as safety measures are put in place, leftover dishes can be consumed to reduce food wastage and food insecurity. Environmental activists also decampaign food dumping claiming that food wastes pollute the environment.