2.2. Inoculation of yogurt cups
The time required for
various
M. circinelloides isolates to produce sufficient CO2 to visibly spoil yogurt cups was determined by inoculating single serving yogurt cups (purchased from a commercial retailer,Geneva, NY) with 104 CFU/g yogurt of sporangiospores from a given M. circinelloides isolate. Adhesive rubber septa (Thermo Fisher Scientific Inc., Indianapolis, IN)were fixed to the foil top and inoculum was delivered via a sterile needle. Cupswere incubated at 25 °C until CO2 production
was visibly detectable.