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  • Fruit storage

    In metabolic processes, fresh fruits exchange gases with the surrounding air. For example, apples constantly absorb oxygen when they respire and return a similar amount of carbon dioxide to the environment. A change in the concentration of gases involved in the respiratory metabolism of fruits affects their breathing processes. These processes can be regulated, for instance by reducing the oxygen content. Minimising the levels of oxygen present delays processes of fruit and vegetables ripening and deterioration, and hence extends their shelf life.

  • Controlled atmosphere

    Controlled Atmosphere (CA) is a food storage technology designed to reduce oxygen content and increase carbon dioxide content in warehouses or ship holds to extend the shelf life of goods, in particular fruit. In addition, temperature and humidity levels can be controlled, as well.

  • CA - transport and storage

    By using a controlled atmosphere fruit respiration processes can be reduced by approx. 50% (on average) as compared to storing in the ambient atmosphere conditions.

    Therefore, for instance, the time of transport and storage can be extended. That means that fruit which normally can be transported only by air cargo can be also transported in containers on ships.
    Using CA in transport has many advantages, as sea freight is more cost-effective and generateslowerCO2 emission during the journey.

    Introducing nitrogen gas into warehouse slowers the oxygen content to the required level. For instance, while transporting fruit and vegetables by ship, a constant supply of nitrogen needs to be ensured. On-site nitrogen generation systems based on oxygen separation from compressed air technology are used in this type of solutions. These systems apply membrane or PSA (Pressure Swing Adsorption) technology. Such plants can be installed locally on the ship/stationary by the warehouse, or using a mobile sea container.

    Fruit and vegetables storage is not the only application for nitrogen in the warehousing industry. Nitrogen is used to preserve dry goods, such as cereals, nuts, spices, seeds, coffee, etc. These products can be stored and transported in the CA. For these commodities, CA usually ensures pest and insect control. Most insects cannot exist without oxygen. To kill all stages of pests, the oxygen level must be reduced to less than 1% oxygen volume in the warehouse. The exposure time depends on the type of pest, but in some cases it can take up to 10 days of uninterrupted CA application.

    Transport and storage in a controlled CA atmosphere gains increasing popularity. The currently used chemicals are phased out as a result of recently introduced pro-health international regulations.

    Typically, nitrogen with a residual oxygen content of 1-5% is used for this type of applications.