Inactivation of microbes by ozone in the food industry: A review

Ozone is active against a broad spectrum of microorganisms. Ozone treatment can enhance safety and increase shelf life with limited impact on product quality. Ozone is known to be one of the strongest oxidizers that can have applications in foods. In the gaseous state, ozone is denser than air, colorless at lower concentrations and possesses a distinct odor. Ozone can be generated using a few methods, by photochemical procedures specifically UV light, electrolysis of water, with corona discharge being the most common method. In the food processing industry, ozone acts as a powerful sterilizer against both Gram-positive and Gram-negative bacteria, bacterial spores, fungi, viruses, and protozoa. Ozone affects the unsaturated lipids in the cell membrane causing leakage of cellular components that can lead to cell death. There are numerous examples to show that ozone has been successfully applied in food processing, specifically in sanitation by disinfecting food plant equipment and contact surfaces, packaging materials, water, air in storage and refrigeration systems, and for foods such as dried and fresh fruits and vegetables. The shelf life and quality of different food products can be maintained using ozone through reduction of spoilage microorganisms.   Key words: Ozone, food, inactivation, sanitation, bacteria.