Foods are exposed to some factors that cause food spoilage and unfitness for consumption. The food spoilage process is considered part of the cycle of elements in nature, the life cycle. Corruption affects the nutritional value of food and its ability to be consumed.
Food is said to be spoiled if there is any change in it that affects its sensory properties, such as a change in taste, color, smell, or any change in the chemical composition.
The extent of food spoilage
The perishability of foods varies and is divided into three types
- Perishable foods: These are foods that cannot be preserved in the normal atmosphere for a long time due to the high moisture content in these foods, such as [fish, meat, leafy vegetables]
- Slow spoilage foods: They are foods that can be preserved in the normal atmosphere for a period ranging from several weeks to several months due to the low percentage of moisture inside them and the presence of peels or protective covers that prevent the activity of spoilage factors such as [potatoes, oranges, apple]
- Foods that almost never spoil: They are foods that resist spoilage factors and can be preserved in the normal atmosphere between several months to several years, provided that they are kept away from any source of external moisture or insects, and they can stay for a long time due to the lack of moisture inside them, such as [cereals, legumes, dates]
Causes of food spoilage
- Fungi: Fungi grow on the surface of acidic foods, forming green, brown, or black fluffy growths
- Bacteria: such as the botulinum bacteria that causes botulinum poisoning on some foods such as fish, meat and some vegetables, as these bacteria secrete toxic substances that are lethal to humans and cause bloating and gases in the canned food.
- Yeasts: There are two types of yeasts:
- Yeasts that tolerate high concentrations of sugar up to 70%, such as jam and jelly
- Yeasts that grow on local solutions whose concentration reaches 15%, such as those that grow on the surface of pickles, have a white color.
- Enzymes: There are four different enzymes
- Proteolytic Enzymes: protease enzyme
- Carbohydrate-degrading enzymes: amylases enzyme;
- Lipolytic enzymes: Lipase enzyme
- Pectinolytic Enzymes: pectenase enzyme
- The interaction of metals with food components: such as the interaction of metal cans with preservatives inside food
- The interaction of food and air: such as the oxidation of vitamin C and the oxidation of the pigment in meat to a brown color
- Contamination of food with some chemical compounds: such as contamination of food with pesticides and fertilizers
- Exposure to mashing and perishing: Exposing food to mashing or perishing during transportation or manufacturing causes it to spoil
- Unsuitable environmental conditions: placing food in an unsuitable environmental condition that causes it to spoil, such as placing it in a damp or high-temperature place.
- Insects and rodents: Insects and rodents cause food spoilage and cause losses of up to 50%
How to keep foods from spoiling
- Keep vegetables and fruits separate from each other
- Do not overfill the refrigerator and place the foodstuffs in order on the shelves so that the cold reaches them evenly
- Avoid washing fresh produce before placing it in the refrigerator so that it does not retain moisture and spoil
- Do not put hot food directly in the refrigerator, let it cool down first
- Freeze foods that you don’t use frequently
- Make sure that the foods that are placed outside the refrigerator are not reached by insects or rodents
- Make sure that the air does not reach the oxidizable food
- How long can I keep leftovers in the refrigerator?
- Washed and cut fruits will keep for 3 to 5 days
- Hermetically sealed cooked vegetables will keep for 3 to 7 days
- Legumes keep from 7 to 10 days
- Bread can be kept for 5 to 7 days
- Rice is stored hours after cooking, i.e. it is not left outside for a long time and is consumed within two days
- Meat and poultry keep from 3 to 4 days
How do I know if the food has gone bad?
It is important to check the validity of the food you have and make sure that it is still usable and get rid of spoiled food to avoid diseases and poisoning. There are several signs of spoilage such as changing its appearance, texture or taste, bad smells coming out of it, or the presence of mold on its surface when any of these occur. Marks in your food get rid of it quickly and make sure to clean the box that contained the food and clean the refrigerator