In the 21st century, different foods are exposed to countless contaminants of all kinds. One of the less visible problems that can pose a health risk is the presence of metal oxides in food. These oxides form when metals react with oxygen, reaching food in various ways. with the danger that this poses to health.
In the next article we are going to tell you What happens to metal oxide in food? and what are its effects on the body.
What are metal oxides?
Metal oxides are chemical compounds that are formed by the reaction of a metal with oxygen. The most common compounds are the following:
- Iron rusts and forms ferric oxide.
- Aluminum oxidizes and gives rise to to a layer of aluminum oxide.
- Copper can oxidize and form copper oxides.
How do metal oxides get into food?
Metal oxides can contaminate food due to different forms:
Cookware
Kitchen utensils that come into contact with food, such as pots and pans, can corrode and release metal oxides. For example, uncoated iron can rust in humid and acidic conditions.
Metal containers
Metal containers are widely used in the food industry. If they are not well coated, the acids present in the food They can attack the metal and cause the formation of oxides that end up in food.
Environmental pollution
Crops can be contaminated due to the presence of metal particles that come from the ground, water or airIndustrial activities or irrigation with contaminated water can leave behind metal residues that oxidize over time.
Thermal processes
If food is cooked at high temperatures on metal surfaces, reactions between the metal and oxygen can occur, resulting in to the formation of oxides in food.
How do metal oxides behave in food?
Solubility and bioavailability
The real danger of a metal oxide will depend largely on of its solubility. In this way, while iron oxide is insoluble, copper oxide can be dissolved in the stomach by gastric juices.
Chemical reactions
Metal oxides may have some involvement in oxidation-reduction reactions that reach to affect the quality of food or alter the color and flavor.
Thermal stability
Some oxides withstand heat well and do not decompose easily during cooking. Others, on the other hand, they can decompose and cause certain problems.
Health risks of metal oxides
The main health risks of the metal oxides are the following:
Acute or chronic toxicity
- Lead oxide: It is very toxic and can affect the nervous system.
- Cadmium oxides: They are related to kidney damage and carcinogenic effects.
- Iron oxides: They are not too toxic although in the long term they can cause certain problems.
- Zinc oxide: Excessive use may result in nausea or vomiting.
Accumulation in organs
Some metal oxides can accumulate in organs such as the liver or kidneys and cause great damage over timeHeavy metals such as lead and mercury tend to accumulate in these areas of the body.
Interference in nutrients
Metal oxides can interfere in the absorption of essential nutrients. Thus, excess iron can hinder the absorption of zinc and copper.
Effects on food quality
In addition to the health risk, the presence of metal oxides can have a negative impact in the quality of food.
Color changes
Many oxides have a series of colors which can cause food to appear unappetizing to eat.
Change in taste
Iron and copper can alter the taste of food.
Reduction of food shelf life
Metal oxides can reduce the shelf life of food, especially in the case of those that are high in fat such as sauces or processed meats.
Controlling and regulatory standards
- The food industry must use food-grade stainless steels to prevent the formation of oxides.
- Coatings on metal containers are key to avoiding direct contact between food and metal. These coatings must be free of harmful substances.
- Control of both equipment and surfaces is key when it comes to preventing corrosion and the formation of oxides.
- It is very important that food industry workers carry out certain hygiene practices, properly maintain the different equipment and are able to detect different metal contaminants.
In short, the presence of metal oxides in food is something that occurs with some frequency in the food world. Although some oxides do not usually represent any type of health risk, others may have. toxic effects for the body or degrade the quality of the food. In response, it is important to follow a series of preventive measures to help prevent the formation of metal oxides in food. A thorough understanding of the different contaminants will help protect health and ensure safe, high-quality food.