Microorganisms associated with black truffles (Tuber melanosporum) from Argentina during postharvest storage

The microbiological quality of truffles produced in Argentina was evaluated by analyzing the bacteria and fungi associated with fresh ascomata, the fungi that developed after storage (15 days in domestic refrigerator and industrial cooler), and those present in deteriorated truffles. Counts of mesophilic aerobic bacteria, Enterobacteriaceae family members, moulds, and yeasts were performed. Fungal identification was achieved by phenotypic analysis of cultures and sequence analysis of the ITS and CaM markers. The initial microbial load was low but increased during storage, as expected. A diverse fungal community was recovered under each condition. In total, 21 taxa belonging to 16 genera were identified from the peridium (25 strains) and the gleba (18 strains). The Hypocreales (Ascomycota) were the dominant taxa (70 %). In deteriorated truffles, 14 different taxa were identified, with only 4 species in common with the healthy ones. Overall, the fungal community isolated from local truffles significantly differs from those reported in previous studies from the Northern Hemisphere.