Construction of a computer‐controlled thermoresistometer for the determination of the heat resistance of bacterial spores over the temperature range 100 to 150°C

Summary A computer‐controlled thermoresistometer for the determination of the heat resistance of bacterial spores has been designed and constructed. The thermoresistometer is capable of operating between 100 and 150°C0.1°C with exposusre times as short as 0.1 sec. Five samples (0.01 ml) of spore suspension can be exposed to steam at each time/temperature combination using a computer‐controlled piston‐driven exposure system. Temperature control of the apparatus is achieved using platinum resistance probes linked to the computer, which then actuates a variable steam control valve.