Gas flushing was shown to be less efficient than high barrier foils (+AP agents) for shelf life extension of Bb conidia in the present study due to higher than desirable aw following the flushing procedure, persistent problems with air leakage, and likely also due to the incapacity of gas flushing protocols to remove all O2. Teshler et al. (2007) reported a residual O2 concentration of 0.26% following gas flushing of foil bags. On the other hand, in our study aw remained at constant low levels following hermetic packaging with foil and use of an efficient O2/moisture absorber. In anhydrobiotic organisms, isolated enzymatic reactions leading to production of free radicals and free-radical mediated non-enzymatic reactions may take place. For example, phospholipid degradation reactions may occur, with detrimental accumulation of their byproducts (fatty acids) in membranes (McKersie et al., 1988). However, aging under O2-free and extremely dry atmospheric conditions is consid- erably slower than aging under non-hermetic conditions.