Kinetics of freezing and thawing processes for concentrated biomass of lactic acid bacteria

Equations describing kinetics of cooling oflactic acid bacteria frozen preparations at the temperatures of-196 °C and-78 °C as well as thawing of such preparations at the temperature +3 7 °C were developed for the sample diameter from 7 to 59 mm. The time constants ('t) for every sample diameter were evaluated which enabled us to calculate the maximum and average freezing/cooling and warming/ thawing rates for the sample diameters studied. Derived equations allowed also for estimation of time, after which the sample reaches required temperature.