Kinetics of mould growth in the stored barley ecosystem contaminated with Aspergillus westerdijkiae, Penicillium viridicatum and Fusarium poae at 23-30 °C.
BACKGROUND
Owing to the lack of a rapid method for determining fungi on cereals, the best way to enhance the safety and nutritive value of stored grain is to develop prognostic tools based on the relationship between easily measurable online parameters, e.g. water activity (a(w)) and temperature (t) of grain, and fungal growth. This study examined the effect of unfavourable temperature (23 and 30 °C) and humidity (0.80-0.94 a(w)) storage conditions on mould growth in the stored barley ecosystem with its adverse microbiological state provided by contamination with Aspergillus westerdijkiae, Penicillium viridicatum and Fusarium poae.


RESULTS
Among the applied storage parameters, a(w) turned out to be the main factor affecting mould development. The longest lag phase and period of fungal activation were observed for grain with 0.80 a(w), which was not threatened with fungal development for at least 30 days. However, in grain with 0.92 and 0.94 a(w), fungal activation occurred within 24-48 h.


CONCLUSIONS
The obtained data and the identification of critical points in mould growth may be used to develop a control system for the postharvest preservation of barley based on a(w) and temperature of grain, which are easy to measure in practice.
Institute of Food Technology of Plant Origin, Poznan University of Life Sciences, Poznan, Poland. j.wawrzyniak@up.poznan.pl
Jolanta
J
Wawrzyniak
Antoni
A
Ryniecki
Marzena
M
Gawrysiak-Witulska
D001230:Aspergillus / Q000254:growth & development*; D004032:Diet; D017753:Ecosystem; D005516:Food Microbiology; D059022:Food Safety; D061353:Food Storage / Q000379:methods*; D005670:Fusarium / Q000254:growth & development*; D001467:Hordeum / Q000382:microbiology*; D006801:Humans; D006813:Humidity; D010407:Penicillium / Q000254:growth & development*; D012639:Seeds / Q000382:microbiology; D013696:Temperature