Effects of grain moisture and hermetic storage on fungi contamination and mycotoxin production in oats

This research aimed to evaluate the natural contamination by fungi, production of mycotoxins, fatty acids composition and the intergranular CO(2) concentration in oat grains stored in a hermetic system for 12 months. The oat grains were harvested with 16% of moisture, being dried until 15%, 12% and 9% of moisture. Oat grains with 18% and 21% of moisture were obtained by a rehidrated, setting the grains in a saturated atmosphere for 5 days. The proximate percent composition, fatty acids profile, natural fungi contamination, mycotoxin production and the CO(2) concentration were evaluated. The results were analyzed by analysis of variance and comparisons of means by Tukey's test and regression analysis of datas. The production of aflatoxins (B(1), B(2), G(1)e G(2)), zearalenone and ochratoxin A were not detected. The amount of CO(2) in the intergranular atmosphere in the hermetic storage showed a linear behavior and was directly related to the moisture and storage time. The increasing of the storage time and grains moisture caused the reduction of unsaturated fatty acids, mainly linoleic and linolenic acids.