Water relations of Paecilomyces variotii, Eurotium amstelodami, Aspergillus candidus and Aspergillus sydowii, xerophilic fungi isolated from Indonesian dried fish.

The water relations of four xerotolerant fungi, Paecilomyces variotii, Eurotium amstelodami, Aspergillus candidus and Aspergillus sydowii, isolated from dried salt fish, were examined at 25 degrees C, on media in which water activity (aW) was controlled by NaCl or a glucose/fructose mixture. All fungi were less tolerant of NaCl than glucose/fructose at low aW. P. variotii grew 2 to 3 times faster on glucose/fructose media than on NaCl. The minimum aW permitting germination varied from 0.753 for E. amstelodami and, 0.776 for A. candidus and A. sydowii to 0.793 for P. variotii. At low aW germination was not always followed by growth. In most cases the minimum for growth was 0.02 aW units above that for germination.