Extended use of gamma irradiation in wild mushrooms conservation: Validation of 2 kGy dose to preserve their chemical characteristics

• The application of gamma irradiation at 2 kGy was validated for two edible mushrooms.
• Some chemical parameters showed significant changes after irradiation treatment.
• The detected chemical changes might be considered as acceptable.
• The differences were not sufficient to change mushrooms organoleptic characteristics.
• The antioxidant activity was generally higher in irradiated samples.

Irradiation is recognized by international organizations as a conservation technology, which was previously applied to some wild mushrooms species. Our research group evaluated the effectiveness of gamma irradiation to preserve different samples of highly appreciated species, particularly, Lactarius deliciosus, Macrolepiota procera, Boletus edulis and Hydnum repandum. According to the obtained results and to specific international recommendations on this subject, the 2 kGy dose was selected. Therefore, this dose was extended to Boletus pinophilus Pilát & Dermek and Clitocybe subconnexa Murrill to validate the proposed technology. The results indicated that some of the analysed chemical (specially sugars and fatty acids) and antioxidant parameters showed significant changes after irradiation treatment, particularly in B. pinophilus (probably due to its higher water content). Nevertheless, the obtained differences did not seem to be enough to change the overall characteristics of these mushrooms. Furthermore, the antioxidant activity was generally higher in irradiated samples. In conclusion, the detected chemical changes might be considered as acceptable, when considering the high advantages of gamma irradiation at decontamination and/or disinfestation level.