Ozone’s effectiveness in food preservation is widely recognized, owing to its strong oxidizing properties. It is highly beneficial in various settings, such as cold storage warehouses, refrigerated trucks, restaurants, supermarket coolers, ships, and trains. By applying ozone gas below three ppm/v., it can significantly prolong storage, prevent spoilage, and eliminate mold growth and odor transfer between materials. This is especially useful for a range of products, including eggs, vegetables, apples, cheeses, citrus and other fruits, nuts, poultry, and meats.
The Delicate Nature of Fruit Storage
Fruit preservation demands particular attention due to its high water content (around 90%) and the susceptibility to quick spoilage. The humid environment in storage houses fosters the growth of germ colonies, leading to unpleasant odours and degraded fruit quality. Post-dispatch, thorough disinfection is essential to avoid contaminating new shipments. Ozone plays a crucial role here, preventing mould and bacteria, thus avoiding costly disinfectants and prolonging the storage life of fruit by 20 to 30%. Its deodorising action also prevents flavour transfer between species, such as citrus fruits, enhancing the overall quality and aroma.
Effective Ozonation for Fruits
Starting the ozonation process during transport and packaging ensures the fruit arrives in optimal condition. Intermittent ozonation, especially for varieties like apples, uses a density of two to six mg O3/m3 air. This reduces weight loss and enhances the fruit’s taste and aroma, proving ozone’s effectiveness in maintaining fruit quality during storage.
Extending Shelf Life for Vegetables
Vegetables in storage often produce strong, unpleasant odours due to rotting. Ozone effectively neutralises these odours, ensuring a fresh environment. Sterilising the air entering the storage room with ozone is vital for maintaining appropriate conditions, as the decomposition of ozone due to moisture, walls, packaging materials, and stored goods necessitates a perfect distribution of ionised air. A slight ozone concentration (0.01 to 0.04 ppm) ensures a fresh atmosphere, enhancing the aroma of fruits like strawberries and preventing odour transfer from packaging materials.
Impact on Metabolism and Odour Control
Ozone’s influence extends to controlling fruit metabolism by oxidising metabolic products and promoting wound healing, thereby preventing further infection. In refrigerated stores, ozone prevents mould colonies on walls and packaging materials, essential for maintaining fruit quality. The rapid decomposition of ozone allows safe human entry into storerooms shortly after ozone generation stops, making it ideal for rotating stored goods.
Specific Applications for Different Products
- Bananas: Require careful ozone concentration control (1.5 to 7 ppm) to prevent physiological injury and manage ripening without altering respiration rates.
- Oranges: Insensitive to higher ozone concentrations (up to 40 ppm), benefiting from slowed ripening due to ethylene oxidation.
- Berry Fruits: Mould growth in strawberries, raspberries, and grapes is preventable with 2 to 3 ppm ozone, effectively doubling storage life.
- Apples and Pears: Show improved storage life with controlled ozone levels, avoiding biological disturbances.
- Lemons: Ozone at safe concentrations can destroy odour-causing compounds, requiring careful ventilation before human access.
Preserving Dairy, Meat, and Fish
- Eggs: Ozone controls mould between the shell and membrane, extending shelf life up to eight months.
- Cheese: Prevents new mould growth and reduces airborne spores without affecting flavour.
- Meat and Poultry: Ozone inhibits bacteria such as psychrophilic bacteria, micrococci, salmonella, and chromogenic bacteria, essential for preserving meat quality.
- Fish: Ozone reduces fishy odours and slows decay by controlling surface bacteria, with ozonated ice extending freshness.
Enhancing Vegetable Storage
Similar advantages apply to vegetables, where ozone neutralises unpleasant odours, prevents microbial growth, and preserves nutritional value. For instance, ozonized potatoes show increased starch and vitamin C content while reducing sugar content, effectively stopping mould growth.
Ozone’s Role in Transport and Refrigeration
Ozone is a powerful oxidant in refrigerated storage and transport of perishable goods by sea, air, rail, and road. It eliminates bacteria, moulds, and odours, preserving various food products’ quality. Ozone’s benefits are evident across multiple applications:
- Banana Importers: Use ozone to control ripening processes in storage containers.
- Fish Storage: Ozonation reduces fishy odours and slows decay.
- Container Charter Companies: Utilise ozone to remove odours from returned containers.
- Transport Companies: Ozonize containers to prevent cross-tainting and improve produce shelf life.
- Pasta Factories: Implement ozone in ducting systems to neutralise odours.
- Cheese Manufacturers: Use ozone fogging units to combat airborne bacteria.
Ozone Applications and Benefits
- Deodorization – Ozone effectively removes odours from storage areas, preventing cross-tainting and ensuring different food products can be stored together without affecting each other’s quality.
- Prevention of Cross-Tainting – Ozone destroys organic substances responsible for cross-tainting, allowing various foods to be stored together without absorbing each other’s odours.
- Ethylene Gas Destruction – Ozone breaks down ethylene gas, delaying fruit ripening and preserving produce during transport.
- Mould, Yeast, and Mildew Prevention – Ozone prevents fungal growth in humid storage environments, maintaining food quality.
- Bacteria Control – Ozone kills surface bacteria on stored food and in the air, ensuring a clean and safe storage environment.
- Remedial Action – Ozone treatment can salvage tainted food cargoes, making them fit for consumption again.
- Vermin Control – Ozone effectively disinfects storage areas, eliminating vermin and preventing cross-contamination between shipments.
- Shipping by Sea – In shipping, ozone controls fruit ripening by breaking down ethylene gas, preventing premature maturation and ensuring optimal quality on arrival.
- UV Radiation and Ozone for Meat Preservation – Ozone, combined with carbon dioxide, is crucial for preventing mould growth on meat during shipping. It controls psychrophilic bacteria, chromogenic bacteria, and salmonella, ensuring safe and high-quality meat products.
Ozone’s multifaceted benefits make it indispensable in modern transportation, storage, and warehousing. Its ability to control odours, prevent microbial growth, and extend the shelf life of various food products underscores its value in maintaining food quality from farm to table.
Contact the Ozone Experts to Harness the Power of Natures Technology: https://www.biozone.co.za/contact/