Food additives and preservatives can help to improve the taste, appearance, nutritional value, and shelf life of certain foods. However, they can also have a potentially harmful effect on our health – especially if we consume too much.
While many food additives, such as plant-based spices and inorganic salts, are still largely derived from nature, others are synthetic compounds that have been manufactured in a laboratory. Commonly used in industrial-scale food processing, these types of additives have been linked to long-term medical conditions like diabetes and even certain types of cancer.
But don’t worry, not all food additives and preservatives are bad for us. Some additives, like vitamins and minerals, can actually improve the nutritional value of food and benefit our health in the long run. Read on to learn more about the positive and negative effects of food additives and preservatives.
In this post:
What are food additives and preservatives?
All preservatives are classed as food additives, but not all food additives are food preservatives. In some cases, a food additive can have more than one function. For instance, ascorbic acid – an antioxidant nutrient commonly found in citrus fruits – also functions as a preservative when added to processed foods like cereal and cured meat.
Various types of inorganic and organic compounds are used as food preservatives. Some of these are traditional ingredients that have been handed down over hundreds, if not thousands, of years. Although the preparation and methodology may have changed over time, many types of food preservatives still follow the same basic principles.
Sodium chloride (common table salt), for example, has been used by humans to preserve foods like ham and fish for thousands of years. So, how does it work? Firstly, the salt desiccates food by removing water from the cells through osmotic actions. It then prevents bacterial and fungal growth through dehydration and by interfering with microorganisms’ metabolism. Edible acidic substances like vinegar, on the other hand, kill mould and bacteria by changing the molecular structure of the proteins and lipids of the cells. This process is called denaturation. Essentially, the acid breaks the weak hydrogen bonds between chains of molecules like amino acids. This is why pickled vegetables and fruits can be preserved for several months.
Other common food additives that are used as preservatives include:
- Tert-butylhydroquinone (TBHQ)
- Citric acid
- Calcium propionate
- Sodium benzoate
- Potassium sorbate
Benefits of food additives and preservatives
One of the main benefits of food additives and preservatives is that they make it possible to store food for longer without the need for refrigeration.
It’s no surprise then that food preservatives and additives have become integral to the food processing and manufacturing industry. Supermarket chains and other food-based retailers also rely on them.
As well as prolonging the shelf life, additives and preservatives can also improve the taste, texture, colour, odour, and aesthetic appeal of food. For instance, anticaking agents can be added to prevent lumpiness, while monosodium glutamate is sometimes used to enhance the umami flavour.
Another key benefit of food additives and preservatives is that they can be used to fortify certain processed food with vitamins and minerals, thus helping to improve their nutritional value.
Disadvantages of food additives and preservatives
Although they have their benefits, there are also disadvantages to food additives and preservatives. As we explain later on, some artificial additives contain chemicals that have been linked to both acute and chronic diseases like diabetes, obesity, digestive disorders, and asthma. Using food additives and preservatives can also reduce the nutritional value of some types of food. As a result, these foods then need to be fortified with nutrients, which means adding more chemicals during the manufacturing process.
Additives and preservatives used in food processing
Food additives have a wide range of uses. Some act as preservatives while others are added to improve the flavour or colour of food. Certain food additives are also necessary for maintaining the structural integrity of food over a long period.
Here are some of the major classifications of food additives:
- Anticaking agents
- Artificial sweeteners
- Flavour enhancers
- Foaming agents
- Thickeners and vegetable gums
- Stabilisers and firming agents
- Flour treatment
- Raising agents
- Bulking agents
Preservatives are the most common type of food additive used in the food processing industry. There are lots of different types of food preservatives, but some of the main ones are listed below.
Butylated hydroxy anisole
First introduced in 1947, butylated hydroxyanisole is a preservative that’s added to edible fats and fat-containing foods to prevent them from going rancid. Although there’s no definitive evidence that it can cause cancers in humans, it is considered to be a risk factor.
Butylated hydroxytoluene is a type of antioxidant that’s sometimes used to preserve food and help maintain the flavour, colour, and texture. Although it’s generally considered safe, some food companies have voluntarily stopped using it.
Calcium propionate is a preservative that’s found in many food products, particularly baked goods. It helps to keep bread and other foods fresher for longer by preventing the growth of microorganisms such as moulds. Following extensive research, calcium propionate is generally recognised as safe to eat. Harmful effects of food additives and preservatives
As we’ve already explained, not all food additives and preservatives are harmful. However, some do cause minor irritations and allergic reactions, while others increase the risk of cancer and life-threatening diseases.
For example, both nitrites and nitrate compounds, which are commonly used as food preservatives for meat and canned foods, have been positively associated with breast and prostate cancers.
Some people can develop a hypersensitivity to food additives, which can cause symptoms like urticaria, angioneurotic edema, and contact urticaria. Additives, such as azo dyes and benzoic acid, may aggravate existing skin conditions or trigger hypersensitivity reactions.
Some people with asthma are hypersensitive to sulphite additives, which can exacerbate underlying breathing problems. Sulphite additives are commonly found in processed potatoes, shrimp, and dried fruit, as well as certain types of beer and wine. Other food additives that may trigger an asthma attack are yeast and monosodium glutamate.
Processed foods that are loaded with additives and preservatives can irritate the epithelial lining of the intestines. This can lead to inflammation, which may affect bowel movements. Consuming too much processed food can also cause an imbalance in the microflora in our digestive system. If you have a sensitive digestive system, you might need to avoid foods that contain gluten, emulsifiers, and organic acids.
How to avoid food additives and preservatives
The best way to avoid food additives and preservatives is to limit your intake of processed foods and avoid snacking on junk food like crisps.
Instead, consider preparing your own food using fresh ingredients. As well as being much healthier, you’ll also know exactly what’s in your food.
Food additives and preservatives are commonly added to food to extend its shelf life and improve properties such as taste, colour, texture, and appearance. Some types of food additives may have adverse effects, depending on your sensitivity. However, not all food additives are bad for us. Many are harmless in moderation, while others can actually be beneficial for our health.