title: [Influence of the interaction of temperature and water activity on the production of ochratoxin A and the growth of Aspergillus niger, Aspergillus carbonarius and Aspergillus ochraceus on coffee-based culture medium].
abstract: In the present study, the effect of temperature and water activity on fungal growth and ochratoxin production on coffee-based medium was assessed. Optimal growth of three Aspergillus strains was observed in the same ecological conditions, namely 30 degrees C and 0.99 water activity. Maximal daily growth is 11.2, 6.92, and 7.22 mm/day for Aspergillus niger, Aspergillus carbonarius, and Aspergillus ochraceus, respectively. However, ecological conditions for optimal ochratoxin production vary according to the toxinogenic strain, with water activity as a limiting factor. Such an ochratoxin A production is inhibited at 42 degrees C and 0.75 water activity. Correspondence between laboratory tested water activity and that measured on a sun-dried ripe cherry batch shows that the first 5 days of drying are critical for fungal growth and ochratoxin A production. Accordingly, artificial drying of cherries at temperatures above 42 degrees C will impede not only fungal growth but also contamination with ochratoxin A.
authors: Laboratoire de génie chimique, Unité mixte de recherche 5503, Equipe Génie des systèmes microbiens , INP/ENSAT, Avenue de l'Agrobiopole, B.P. 32607 Auzeville Tolosane, 31326 Castanet Tolosan, Toulouse, France.
authors: Ahou Irène
authors: AI
authors: Kouadio
authors: Ahmed
authors: A
authors: Lebrihi
authors: Georges N' Zi
authors: GN
authors: Agbo
authors: Florence
authors: F
authors: Mathieu
authors: Annie
authors: A
authors: Pfohl-Leszkowiz
authors: Mireille Bretin
authors: MB
authors: Dosso
mesh_terms: D001230:Aspergillus / Q000254:growth & development* / Q000378:metabolism*; D003069:Coffee / Q000382:microbiology*; D009793:Ochratoxins / Q000096:biosynthesis*; D013696:Temperature; D014867:Water / Q000378:metabolism
chemical_list: D003069:Coffee; D009793:Ochratoxins; D014867:Water; C025589:ochratoxin A