How Preservatives Keep Food Fresh Even on the Shelf
Preservatives get a bad reputation, but they are actually the key to keeping most shelf-stable foods fresh and safe. This is how they work and what you should know about them when you see them on food labels.
Most preservatives focus on two main reasons food spoils: germs (fungi, bacteria) and oxidation . Creating an unfavorable environment for microbes is one way to drive them away. Traditional methods include pickling, fermentation, and salting. While these traditional methods are still in use today, artificial preservatives are also often used to extend the shelf life of many foods. Artificial acids inhibit microbial growth, including benzoic acid in salad dressings and propionic acid in baked goods.
Regarding oxidation, there are both traditional (smoking) and modern (BHT, vitamin E) methods of antioxidant protection. Both help prevent rancid tastes in foods such as butter, cheese and cereals. Citric and ascorbic acids prevent browning of foods and slow down the enzymatic reaction that leads to spoilage. The video above is much more detailed and well worth watching if you’re wondering how they work and why our food industry relies on them so much.
Are preservatives bad for you? | TED-Ed (YouTube)