What are preservatives and what are common examples used in food?

 

What are preservatives and how do they work?

Preservatives are food additives that play an important role in making foods last longer or taste better. Specifically, preservatives help to control and prevent the deterioration of food, providing protection against spoilage from micro-organisms (e.g., bacteria, yeast, moulds), life-threatening botulism and other organisms that can cause food poisoning (antimicrobial function).1 High-risk foods such as meat, seafood, dairy, and cheese serve as a breeding ground for potentially dangerous micro-organisms, therefore, the addition of a preservative is usually required to ensure food safety.2 Next to spoilage caused by micro-organisms, it can also be brought about by chemical (e.g., oxidation) or physical (e.g., temperature, light) factors.1 Preservatives are also used to prevent these types of spoiling reactions in order to prevent any alterations in foodstuff’s taste or, in some cases, their appearance (antioxidant function). Without the addition of a preservative, certain foods may turn rancid or change in colour. Ultimately, preservatives protect the quality of foods and beverages, reduce food cost, improve convenience, lengthen shelf-life, and reduce food waste.

Besides the use of food additive preservatives, foods can also be preserved by different processing methods like canning, dehydration (drying), smoking, salting, freezing, and the use of packaging.4 Some practical examples include the canning of jams and tomato sauce, drying fresh fruits to make dried fruit, and adding salt to cabbage to make sauerkraut. In this article, however, we will focus on food additive preservatives only.