- What causes food spoilage and how can we avoid or delay this process?
- Microorganisms that break down food
- How to control the causes of decay?
- Non-perishable foods and their decomposition
- References
The decomposition of food occurs for various reasons. Since food is organic matter, spoilage by microorganisms and oxidation are the main causes of spoilage.
In decomposition, temperature is an important factor, since at high temperatures microbiological and oxidation reactions occur faster. At low temperatures decomposition takes place more slowly.
Fruits decomposed by the action of microorganisms
Other important factors in the decomposition of food are pressure, humidity and the carbon-nitrogen ratios of the food. These factors can also influence the action of microorganisms and the oxidation of food.
What causes food spoilage and how can we avoid or delay this process?
Microorganisms that break down food
The most common cause of food spoilage is the proliferation of microorganisms.
Bacteria belonging to genres as varied as Pseudomonas, Bacillus or Clostridium, among others, are important causes of food decomposition. Also fungi like Aspergullus and Penicillium cause food spoilage.
In some cases the breakdown of food by specific bacteria can lead to infections if the food is eaten.
The bacteria most commonly associated with spoilage infections belong to the genus Salmonella.
At present there is great concern about the effects of climate change on the action of microorganisms that decompose food.
It is feared that global warming will increase the rate at which these microorganisms act, making food more difficult to preserve.
How to control the causes of decay?
Eating spoiled food can have various effects on human health. Therefore, there are several mechanisms to stop or slow down its decomposition and thus keep food in good condition for a long time.
Freezing is the most common way to preserve food. The effective temperature to retard the growth of microorganisms and the consequent decomposition of food should be less than 10 ° C.
One of the most common ways is vacuum packaging. This type of packaging allows keeping oxygen concentrations low to prevent the microorganisms responsible for decomposition from growing.
The causes of spoilage can also be avoided by adding extra substances to food that inhibit the causes of spoilage.
These substances are known as preservatives and can be chemical compounds such as sorbic acid or biological compounds such as lactic acid bacteria.
Non-perishable foods and their decomposition
Non-perishable foods are those that can take a long time to decompose and their decomposition does not depend so much on the characteristics of the food itself, but on eternal factors.
Examples of non-perishable foods are grains such as rice and beans, and canned foods.
The most common cause of non-perishable food spoilage is contamination with an external agent, usually a microorganism such as fungi or bacteria.
Extreme environmental conditions of high temperatures or pressures can also lead to their decomposition.
In the case of canned food, there is also the phenomenon of flat sour spoilage. This is caused by bacteria that grow in high temperatures and that generate strange smells and tastes although they do not compromise human health.
References
- Aerts R. The Freezer Defrosting: Global Warming and Litter Decomposition Rates in Cold Biomes. British Ecological Society. 2006; 94 (4): 713–724.
- Armando, A. (2003). Biotechnology and food: questions and answers. Spanish Society of Biotechnology.
- Craine JM Morrow C. Fierer N. Microbial Nitrogen Limitation Increases Decomposition. Ecology. 2007; 88 (8): 2105–2113.
- Dolce J. Food infection. The American Journal of Nursing. 1941; 41 (6): 682–684.
- Mcnabb A. Food Control for Summer Resorts. Canadian Public Healt Journal. 1931; 22 (6): 306–308.
- Public Society for Science & the Public. Food Science. Science News. 1986; 129 (3): 42–43.
- Selvam A. Yun S. Yang X. Wong J. Food waste decomposition in leachbed reactor: Role of neutralizing solutions on the leachate quality. Bioresource Technology. 2010; 101 (6): 1707–1714.