Text Box: Kitchen table science, eye-balls, and nose can go only so far.  Sample material was  submitted to Rtech Laboratories, Arden Hills, MN for analysis of Clostridium perfringens content.  Rtech serves food preparation industries with a variety of biological and chemical analyses performed in accord with U.S. and international standards.

 Dry ingredients for corn meal and oak bark starters  in separate containers were shipped to Rtech where warm water was stirred in prior to incubation at 37C (98F).  Per the Rtech report: "The set-ups developed a strong cheesy odor and gassed.  Samples were tested for Clostridium perfringens at 26 hours from hydration.
Bark - 1,300,000 Colony Forming Units per milliliter (CFU/ml)
Corn - 9,700,000 estimated CFU/ml   Estimated count because plates were overgrown by the extremely high population."

 Samples of bread made from corn meal and bark starters were also analyzed with the determination that C.perfringens was below the detection limit of 10 CFU/g.  To detect C.perfringens, the sample is incubated in a solution congenial to perfringens spores.  A proper sample of the solution is examined under a microscope to count colonies and the count interpreted in terms of sample weight or volume.

 The Rtech analyses confirmed presence of perfringens in the starters and, accepting detection limits, its absence in salt-rising bread made from identical starters.

 The term "Clostridium perfringens " is applied to a many similar organisms.  Five variants (A, B, C, D, E) are distinguished by the toxin they produce; other variants do not generate toxin according to my limited understanding.  Toxins from all variants are heat labile and destroyed at temperatures above 150F.  Perfringens feeds on protein (gluten in flour) rather than starch or sugars.   R. J. Robinson states "Even though this organism causes food borne gastroenteritis, it is harmless when used as a leavening agent because it dies during baking.  No food poisonings have ever been attributed to salt rising bread.  (1967)."   In private communications, contemporary perfringens researchers also assure me that toxins have never been detected in food stuffs.  The toxin is created as the bacteria transitions to, and perhaps from, the spore form.  Spore action occurs  in warm, moist, anaerobic environments such as the human intestine.  Most SRB does not resemble the interior of an intestine.