The multiplication constant of a microorganism in a colony is normally reduced by irradiation but still remains as a characteristic constant-A new approach to determining irradiation pasteurization doses

This work is based on a previous observation and on a related mathematical modeling regarding the linear growth of a colony of microorganisms under given conditions. We had previously shown that the growth rate of the colony is merely proportional to the individual exponential multiplication constant, , of the microorganisms.Tiny colonies of penicillium are subjected to different doses of irradiation. The subsequent observation of the colonies' growth rate beautifully furnishes a measure of how the multiplication constant, , of the microorganism is affected by irradiation.The plot of with respect to the irradiation dose, shows a linear interdependence between the two quantities. The extrapolation of this plot easily yields the radiation pasteurization dose of the microorganisms in hand.