The influence of storage conditions on bee pollen contamination by microscopic fungi and their mycotoxins

Abstract

The aim of the experiment was to determine the effect of storage duration at different ambient temperatures on bee pollen contamination by microscopic fungi and their mycotoxins. The dilution plate technique was used for isolation of fungi from the samples. The contents of mycotoxins aflatoxin (AFL), ochratoxin A (OTA), deoxynivalenol (DON), zearalenone (ZEN) and T-2 toxin (T-2) were analysed by the direct competitive enzymelinked immunosorbent assay (ELISA) method. Toxin-producing fungi, belonged to Penicillium, Aspergillus and Fusarium spp., isolated during bee pollen storage with a total amount varying from 1 × 10 to 3.5 × 103 cfu g-1. The amount of toxin-producing fungi was the lowest in the bee pollen stored for 1 month at 8‒9°C temperature: it varied from 1 × 10 to 2.1 × 103 cfu g-1. After 4 months of storage at 20‒22°C temperature, the highest contamination of bee pollen was found: it ranged from 2 × 10 to 3.5 × 103 cfu g-1. Contamination with toxins AFL, OTA and T-2 in all bee pollen samples was found to be below the limit of detection. Mycotoxins ZEN and DON after 1 month of storage at 8‒9°C temperature were not detected. The highest DON concentration (185 µg kg-1) was ascertained after 4 months of storage at 8‒9°C temperature; the highest ZEN concentration (830 µg kg-1) was found after 1 month of storage at 20‒22°C temperature.