Reducing the Rate of Oxidation of Foodstuffs

Introduction

• Oxidation of foodstuffs, a natural process, can lead to the deterioration of food quality and safety. To mitigate this, various methods can be employed to reduce the rate of oxidation.

Refrigeration

• One effective method to slow down food oxidation is refrigeration. Lowering the temperature inhibits the oxidative reactions that occur in food.

Modified Atmosphere Packaging

• Packaging food under specific conditions can also reduce oxidation. This includes vacuum packaging or packaging with inert gases like nitrogen, which decreases the concentration of oxygen (air) around the food.

Steam Blanketing

• In the production of crisps (potato chips), manufacturers fry potatoes under a blanket of steam. This steam reduces the concentration of oxygen, extending the lifespan of both the frying oil and the crisps.

Antioxidants

• Antioxidants are molecules added to foodstuffs to further prolong their shelf-life. They work by reducing the rate of oxidation reactions that involve the transfer of electrons to an oxidising agent.

Demonstration

• An effective classroom demonstration illustrates the benefits of antioxidants. When an apple is cut in half and one side is exposed to air while the other is coated with lemon juice (rich in antioxidant vitamin C), the untreated side turns brown due to free-radical-induced oxidative damage. In contrast, the treated side remains undamaged, showcasing the protective role of antioxidants.

---

Reducing the rate of oxidation of foodstuffs

Conclusion:

• Slowing down the oxidation of foodstuffs is crucial to maintaining food quality and safety. Methods such as refrigeration, modified atmosphere packaging, and steam blanketing can reduce oxidation rates. Additionally, the use of antioxidants in food products helps minimise oxidative damage, extending the shelf-life of various food items.