Association of moulds to foods

INTRODUCTION The traditional division of filamentous fungi has been between the food spoiling fungi, which were considered opportunistic fungi with no substrate preferences and animal or plant pathogenic fungi with tight associations to their hosts. Most food spoiling fungi have been regarded as saprophytic organisms thriving on any substrate they could encounter and they can indeed be isolated on many different laboratory media. They can grow and differentiate on minimal media containing only nitrate and sucrose as nitrogen and carbon source, as well as on complex media based on cereal, vegetable, fruit and meat, such as peptones, corn steep liquor, malt and yeast extract. (Raper and Thom, 1949; Smith, 1960; Samson et al., 2004c). However, as early as 1949 Westerdijk suggested that certain Penicillia were associated to certain food substrates, such as P. italicum and P. digitatum to citrus fruits and P. expansum to pomaceous and stone fruits.