INVESTIGADORES
PATRIARCA Andrea Rosana
congresos y reuniones científicas
Título:
Modelling the growth of ochratoxigenic Aspergillus carbonarius isolated from Argentinean dried vine
Autor/es:
PATRIARCA, ANDREA; ROMERO, STELLA MARIS; GRACIELA VAAMONDE; RAMOS, ANTONIO J.; MARÍN, SONIA
Lugar:
Lleida
Reunión:
Congreso; Internacional Congress of Postharvest Pathology; 2011
Institución organizadora:
Universitat de Lleida e IRTA
Resumen:
Aspergillus carbonarius is the major responsible for the ochratoxin A present
in grape and its derivatives, such as wine and raisins. The purpose of the
present study was to model the growth of ochratoxigenic strains of A. carbonarius under environmental
conditions which may take place during postharvest and dehydration of grapes and
validate those models with external literature data. Czapek Yeast Extract agar
was adjusted to seven different water activities: 0.80, 0.825, 0.85, 0.87,
0.89, 0.925 and 0.95. Plates were incubated at 15, 20, 25, 30, and 35°C. Both
kinetic and probability models were applied. No growth was observed at 0.80 aw.
Growth data were fitted to the primary model of Baranyi and the maximum growth
rates were modeled as a function of temperature and water activity by several
kinetic secondary models. A cardinal model was the more suitable to describe
the growth kinetics of A. carbonarius.
The developed model was validated on independent data sets from the literature
and presented acceptable goodness of prediction. A logistic regression
polynomial model was applied to predict the probability of growth over time.
The degree of agreement between predictions and observations was 91.3%
concordant. Validation of the probability model with literature data sets
showed high percentages of agreement. Results indicate that the developed
predictive models could be satisfactorily employed to describe the combined
effect of temperature and water activity on the growth of A. carbonarius under the experimental conditions.