Fungi have long been associated with earthy odours. One of the main contributors to this odour is
geosmin, a sesquiterpenoid metabolite produced by soil living fungi. Some food commodities are liable to
contamination by geosmin producing fungi. Under favourable environmental conditions the production of
geosmin occurs. One of the producers of geosmin in fruits is Penicillium expansum which also produces
the mycotoxin patulin. Recent reports indicate that geosmin production by P. expansum is stimulated by
Botrytis cinerea. However, the effect on patulin production is not known. The above issues will be
discussed in this contribution.Fundação para a Ciência e a Tecnologia (FCT
