Influence of water activity on aroma production by Trichoderma viride TS growing on a solid substrate

Abstract

The influence of water activity on 2-heptanone production (cheese aroma) by Trichoderma viride TS cultivated on agar media was evaluated through a headspace gas chromatographic analysis. Modifications in water activity (a_w) led to a number of variations in the aroma production (300% at 7 d). These variations could be attributed both to an increase in the production rate by the cells and to an increase in mycelial density. Optimal aroma production occurred at a_w=0.98, but considering the radial growth, the optimal a_w values were found to be both 0.96 and 0.98.