Aflatoxins are toxic metabolites (i.e. a dangerous chemical substance, not a living being) that are produced by the fungi Aspergillus flavus and A. parasiticus. They grow on food supplies, especially on agricultural products kept in warm and humid atmospheres. They are also a major economic burden, causing 25% or more of the destruction of food crops worldwide each year (WHO 2018).
Mycotoxins and aflatoxins: what are they?
Mycotoxins are metabolites (i.e. a chemical substance) produced by certain types of fungi, which generally grow on products stored in a warm and humid atmosphere. In order to grow, these moulds (fungi) need a temperature between 6 and 50 °C, essential elements (carbon and nitrogen) and water activity above 80%.
Under certain physico-chemical conditions (oxidative stressproduction of free radicalssudden increase in temperature, high humidity, contact with certain fatty acids), these moulds can produce secondary metabolites: aflatoxins.
Aflatoxins therefore constitute a certain category of mycotoxins, which are toxic when consumed: at high doses they can cause death within a few days. At lower and regular doses, the health consequences are more diverse: reduced metabolism (and growth retardation), carcinogenic effect that can affect all organ systems (aflatoxin B1 in particular), mutagenic and genotoxic effect (congenital anomalies in children) and immunosuppression (source WHO 2018). All animals are affected.
The most common aflatoxins found in food and which are subject to quality control are aflatoxins B1, B2, M1, G1 and G2. They can be found in a wide variety of products: wheat, almonds, nuts, pistachio, cocoa, coffee, soy, corn (grain and silage), etc... Every year aflatoxins impact the world's crops: ¼ crops are affected by these substances.
Detection and prevention of aflatoxins
Techniques to analyse and detect the presence and content of aflatoxins in a product are being actively researched.
The official laboratories implement detection by HPLC (high performance liquid chromatography coupled with mass spectrometry). Less accurate but transportable tests for factories and grain silos are also available, using in particular the Elisa enzyme immunoassay method.
In the future, other processes are being developed: hyperspectral imaging, electronic noses, molecularly imprinted polymers, to name but a few. The aim is to provide accessible, robust and transportable solutions.
How to protect yourself against the risk of aflatoxins?
Aflatoxin risk reduction must be achieved through an integrated approach throughout the food chain, from the field to the consumer's table. In particular during the post-harvest phase, prevention involves controlling the physico-chemical parameters of the product (humidity, temperature) and managing external contamination (threats from insects, changes in humidity levels).
A simple solution that is rapidly developing is the preservation of agricultural and food products under a modified atmosphere, which inhibits enzyme activity and the development of aflatoxins.
Nox hermetic big bags allow you to create the optimal sanitary conditions to store your products for a long time and to transport them serenely.
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