Reduced incubation time for Raven spore strips
Raven Biological Laboratories Inc. in the U.S.A. have gained approval for a reduced incubation period of 24 hours for ATCC 7953 G.stearothermophilus spore strips when used in conjunction with their modified Tryptic soy broth with Bromocresol purple indicator.
The Raven Biological Laboratories spore strips containing Geobacillus stearothermophilus
ATCC 7953 and modified tryptic soy broth + bromocresol purple are
designed for use in testing the efficacy of steam sterilization cycles
at 121ºC.-135ºC. Routinely incubation times of 7 days have been required for spore strip/TSB combinations to ensure recovery and growth of any surviving spores before results can be reported. This delay in reporting results may result in significant accumulation of product in pre-release store and significantly increase product production cycles.
Accumulated data from various spore production lots submitted for analysis have now been accepted by the F.D.A. as supporting use of a 24 hour incubation cycle at 60ºC +/-2ºC with the combination of Raven G.stearothermophilus ATCC 7953 spore strips and Raven modified tryptic soy broth with bromocresol purple indicator.