Influence of water activity on Penicillium citrinum growth and kinetics of citrinin accumulation in wheat

• Published in: International journal of food microbiology 1998-07, Vol.42 (3), p.219-223
• Main Authors: Comerio, Ricardo, Fernández Pinto, Virginia E, Vaamonde, Graciela
• Format: Article
• Language: English
• Subjects: ACTIVIDAD DEL AGUA; ACTIVITE DE L'EAU; Biological and medical sciences; BLE; Cereal and baking product industries; Chromatography, Gel; Chromatography, Thin Layer; CITRININ; Citrinin - analysis; Citrinin - biosynthesis; Citrinin accumulation; CITRININA; CITRININE; Food industries; Food Microbiology; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; Kinetics; Pathology, epidemiology, host-fungus relationships. Damages, economic importance; Penicillium - growth & development; Penicillium - metabolism; Penicillium - radiation effects; PENICILLIUM CITRINUM; Phytopathology. Animal pests. Plant and forest protection; Time Factors; TRIGO; Triticum - microbiology; Triticum aestivum; Water - chemistry; WATER ACTIVITY; Wheat; WHEATS
• ISSN: 0168-1605; 1879-3460
• DOI: 10.1016/S0168-1605(98)00081-6

The influence of water activity ( a w) on both Penicillium citrinum growth and citrinin accumulation in wheat was studied. Wheat conditioned at different levels of a w and inoculated with a citrinin producer strain was incubated at 30°C for 2 months. Fungal growth was assessed by microscopic examination. P. citrinum grew down to a w 0.775. Citrinin was not detected in the substrate at a w 0.800 and lower. As a w increased the toxin was detected earlier and the maximum accumulation increased markedly (65 μg/kg at a w 0.810, 460 μg/kg at a w 0.825 and 22 mg/kg at a w 0.885). Citrinin concentration declines rapidly after reaching the maximum at each a w level.