The inhibitory effect of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) mixture on fungal populations, Aspergillus section Flavi and aflatoxins accumulation in in-pod peanuts during storage in big bags was investigated. In-pod peanuts were previously conditioned at different water activities (0.94, 0.88, 0.84 and 0.76 aw) and treated with food-grade antioxidants. Both control and treated peanuts were stored for 6 months and sampled at monthly intervals. BHA-BHT mixture reduced the incidence of peanut fungal populations between 0.6-20.4% and between 1.2-33.1% during 1-3 and 4-5 storage months, respectively. Aspergillus section Flavi counts decreased with 36.5%, 46.3% and 77.4% in peanuts conditioned at 0.94, 0.84 and 0.76 aw levels and treated with antioxidants. At the above peanut aw conditions, the treatment applied reduced aflatoxin accumulation by 72.1%, while any effect on this metabolite production was observed at 0.88 aw. The antioxidant formulation used in this study has the potential to control aflatoxigenic populations in in-pod peanuts stored in half-permeable silos at ≤0.84 aw level.

The aim of this study was to investigate antifungal and insecticidal activity of two microencapsulated antioxidants: 2(3)-tert-butyl-4 hydroxyanisole (BHA) and 2,6-di(tert-butyl)-p-cresol (BHT) against Aspergillus section Flavi and Oryzaephilus surinamensis (L.), a vector carrier of aflatoxigenic fungi on stored peanuts. Susceptibility of Aspergillus section Flavi, insects, and aflatoxin B1 accumulation in sterile peanut kernels conditioned at two different water activities (aw) (0.83 aw and 0.95 aw) was determined with different doses of antioxidant formulations (10, 20 and 30 mM) during 45 days. Moreover, Aspergillus section Flavi isolation frequency from live and dead insects was evaluated. The BHA formulation completely inhibited Aspergillus section Flavi development regardless of aw and doses assayed. Antifungal effect of microencapsulated BHT was highly dependent on aw, with 86–100% fungal inhibition at 20 and 30 mM, at the lowest aw (0.83 aw) and at the end of the experiment. No aflatoxin accumulation was detected in samples treated with the BHA formulation. In general, low levels of Aspergillus section Flavi were detected in dead insects. Our results show efficacy for 45 days, in addition microencapsulated BHT could be an alternative to control peanut pests in dry kernels.

The present study aimed: (i) to develop models for the combined effect of water activity (0.99, 0.94 and 0.90), microstructure expressed as 0, 5, 10 and 20% w/v gelatin, and temperature (15, 20 and 25 °C), on growth and OTA production rates by Aspergillus carbonarius; and (ii) to evaluate the performance of the developed models on food matrices (jelly, custard and marmalade) of different viscosity at pH 5.5. The square root of biomass increase rate (fungal growth rate) and OTA production rate were determined by the Baranyi model and were further modeled as a function of temperature, gelatin concentration and aw by applying polynomial models. Time for visible growth and the upper asymptote of the OTA production curve were also determined by the Baranyi model. Increase in gelatin concentration resulted in a significant delay in all parameters describing fungal growth and OTA production rates, at all temperatures and aw. The effect of microstructure on fungal growth and OTA production rates was less evident at stress conditions of aw and temperature. Detection time for visible fungal growth was markedly influenced by aw and temperature. Coefficients of determination were 0.899 and 0.887 for the models predicting the square root (μₘₐₓ) of growth and OTA production rate, respectively. Predictions of growth rate agreed well with the recorded data of custard and marmalade, while observations of OTA production rate indicated low agreement with model predictions, in all food matrices except for marmalade. The present findings may provide a basis for reliable assessment of the risk of fungal growth and OTA production in foods of different structural and rheological properties.