The presence of corrosive gases inside containers used for transporting perishables can quickly cause chemical reactions within the metals, producing corrosion - even at very low concentrations (ppm).
The main corrosive gases involved are acid gases, which can be split into sulphur compounds (H2S hydrogen sulphide, SO2 sulphur dioxide and mercaptans) and chlorine and derivatives, as well as caustic gases such as ammonia and derivatives.
These gases are easily found inside containers used for transporting perishable foods - whether for fruit, vegetables, meat or fish.
In transporting some fruits (in particular dessert grapes) meta-bisulphite is frequently used to prevent rotting during transportation and subsequent storage. This generates SO2 inside the container - a highly corrosive component whose activity increases when relative humidity increases.
When transporting chilled or frozen meat and fish it is more common to find H2S hydrogen sulphide, mercaptans and ammonia (in the case of fish).
Bleaching, steam cooling and cleaning products are sources that generate chlorine and derivatives such as chlorine oxide, hydrochloric, etc.
Small concentrations of these corrosive gases cause corrosion both of the container itself and the equipment within it. This results in high maintenance costs and a considerable reduction in the usable life of the container.
Being aware of the problem and implementing systems to eliminate corrosive gases in the environment are necessary to achieve better results.
The first step is to carry out an assessment of the situation. Bioconservacion has a fully-equipped laboratory aimed at characterising corrosive gases within the environment, through the use of corrosion coupons.
The technique involves exposing copper and silver coupons within the environment in question for subsequent analysis in the laboratory once the exposure period (usually 30 days) has been completed.
After determining the corrosive gases present within the environment, the most appropriate filtration media for removing them is selected.
Bioconservacion has a wide range of filtration media that have been developed specifically for different corrosive gases.
The method of application proposed by Bioconservacion is very simple and requires no infrastructure investment or special equipment; it simply requires placing the filters with the selected media inside the container.
It is important to note that, because they do not come into contact with the food, these are completely harmless solutions. They do not alter any of the organoleptic properties of the perishable products being transported. Indeed, these solutions are even approved for use with organic products.