A number of times we refrigerate perishable food like vegetables, fruits, meat, fish, and milk so that they have a longer shelf life; however, sometimes we are not aware of how long that food should be kept in the fridge. Nutrition experts say the longer the food stays in the fridge, the more it loses its freshness, taste, colour and smell.

"Although food kept for long may look fine, it is dangerous to eat. Food that has been stored too long in the refrigerator or freezer may be of lessened quality, but most likely would not make anyone sick. However, some bacteria such as listeria monocytogenes thrive in cold temperature, and if present, they will multiply and could cause illness,” says Dr Dieudonne Bukaba, a nutrition expert from AVEGA Clinic Remera, Gasabo District.

According to Mayo Clinic, leftovers can be kept for three to four days in the refrigerator, because if kept past that time, it increases the risk of food poisoning.

Bukaba warns about storing perishable foods like eggs in the fridge, but instead in the carton on a shelf because the temperature of the storage bins in the fridge door fluctuate more than the temperature in the cabinet.

While cleaning the fridge, he says one should avoid using solvent cleaning agents, abrasives, and all cleansers that may impart a chemical taste to food or ice cubes, or cause damage to the interior finish of your refrigerator.

"Refrigeration is essential because it increases the shelf-life of food, especially for perishable food like fruits and vegetables,” says Private Kamanzi, a dietician at Amazon Wellness Centre, Remera in Gasabo District.

He further says refrigerating food helps kill microbes (bacteria that affect food) due to the fridge temperature.

Which food should or shouldn’t be refrigerated?

Kamanzi stresses that foods that are processed like sausages and yoghurt can spend up to a week or month in the fridge, while raw foods like drinks (fresh juice), fruits (mangoes, oranges, tomatoes, blackberries, apples) or vegetables (broccoli, dodo, carrots) shouldn’t be refrigerated for more than a week.

He adds that perishable foods like vegetables, fruits, and proteins should be refrigerated because they can easily be damaged by bacteria.

Kamanzi says foods that shouldn’t be refrigerated when raw include carbohydrates/starch (rice, yams) because they contain a cellular celera that protects them from contamination.

Effects of refrigerating food

Kamanzi says refrigeration causes degradation of natural pigments like chloroplasts that give colour to fruits and vegetables.

He adds that vegetables and fruits are rich in water soluble vitamins like vitamin C and pantothenic acid which are likely to be lost if they are refrigerated.

"When fruits and vegetables are refrigerated, they lose lipoxygenase enzyme which gives flavour and smell to fruits and vegetables especially foods that are rich in beta-carotene like carrots, broccoli and peas, among others

"There is also oxidation of liquids for foods with fats and liquids if refrigerated, which can expose one to different diseases like cancer,” Kamanzi explains.

He emphasises that refrigerating meat causes it to lose flavor, adding that the fridge temperature shouldn’t be below 18 degrees Celsius because this increases oxidation.

Kamanzi also says while arranging food, raw food should be on the first layer, vegetables next, fruits, and protein-rich foods at the bottom.

When refrigerating meat or cooked food, he says it is necessary to cover it to avoid contamination.

"As you refrigerate, don’t mix fruits and vegetables to avoid cross-contamination due to movement of microorganisms or bacteria as some are resistant to raw foods, yet harmful to vegetables,” he explains.

The dietician says loss of texture of food can result from refrigeration, as some food has got soluble fibers needed by the body.

Safety tips

Bukaba says when food is removed from the freezer for defrosting and the unit is turned off, it’s important to keep refrigerated foods cold and frozen foods from melting. This, he says, can be done by placing the food in a cooler with a cold source or having it packed in a box.

He cautions against using any type of electrical heating device, ice pick, knife, or other sharp object to remove frost, as this could damage the inner lining.

"It is also important to keep the fridge clean by wiping it with clean hot soapy water, then rinsing it because if it is dirty, the food can get contaminated,” he adds.

Bukaba explains that, "Hot food can be placed directly in the refrigerator or it can be rapidly chilled in an ice or cold water bath before refrigerating. Cover the food to keep moisture and prevent it from picking odors from other foods.”

For easy storage, he says large pots of food with soup or stew should be divided into small portions and put in shallow containers before being refrigerated.