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This is a dangerous misconception. Bringing botulism spores to 100 Celsius will not kill them, the spores can survive indefinitely at these temperatures. This is literally the reason pressure canning was invented, to heat the liquid to a higher temperature such that botulism spores are destroyed.


No, no it doesn't. You two clearly didn't understand what I wrote. I don't how to explain it any simpler than I already have. Depending on the bacteria and the storage conditions of the canned goods, you might need to hold it to a higher f-value. For instance, canned goods that will be stored in a 25-40C range target an f-value of 12 to 15. The higher the temperature you use, the less time you need. And vice versa. It's a misconception that certain bacteria can only be killed at high heat. Quickly, sure. But, as long as you target the correct f-values, all you need is 100C. And a lot of time.


From Wikipedia:

>Although the botulinum toxin is destroyed by thorough cooking over the course of a few minutes,[26][27] the spore itself is not killed by the temperatures reached with normal sea-level-pressure boiling, leaving it free to grow and again produce the toxin when conditions are right


Ah yes, a pithy phrase from Wikipedia that isn't backed-up at all by the sources. /golfclap

Here, read through all these, and then get back to me if you think you're still correct.

Perhaps this explanation will make it clearer?

http://www.nzifst.org.nz/unitoperations/httrapps2.htm

Something more scientific?

https://www.fda.gov/downloads/Food/GuidanceRegulation/UCM252...

http://aem.asm.org/content/early/2016/07/25/AEM.01737-16.ful...

https://www.food.gov.uk/sites/default/files/mnt/drupal_data/...

http://aem.asm.org/content/34/1/23.long

https://www.mpi.govt.nz/document-vault/11042

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC91518/

http://digitool.library.mcgill.ca/thesisfile115866.pdf

http://nfscfaculty.tamu.edu/talcott/courses/FSTC311/Textbook...

http://spo.nmfs.noaa.gov/mfr452/mfr4521.pdf

http://www.fao.org/docrep/010/ai407e/AI407E22.htm

A Nice explanation of thermal processing food for canning:

https://www.intechopen.com/download/pdf/40352

Textbooks?

Principles of Microbiological Troubleshooting in the Industrial Food Processing Environment See chapter 2.7

Compendium of the Microbiological Spoilage of Foods and Beverages Pages 20-24, 187-188, 210


The FDA source seems to be the best one, and was useful-- thanks for that. I'll concede that I (and it appears Wikipedia) are wrong on this matter.

For future reference, you could probably just list that, and drop the attitude. You should also avoid dumping a glut of studies that you didn't bother to read, and that turn out to be irrelevant to the study; for instance the NCBI study you linked was discussing lysozyme's effect on temperatures and appears to contradict your statements, while the AEM ASM study (34/1/23) doesnt back you up as none of the trials they did went below 104 C, and it showed an inverse logarithmic relationship with decreasing temperature.


I have read them all, but thanks for assuming I didn't. You know why I have an attitude, having to argue these points with people who are arguing based on ignorance and not any knowledge or facts of the matter. Perhaps, not commenting on subjects you know woefully little about would be the more prudent course in the future? This isn't a jab at you, just a general point of annoyance with commentators on the internet that always irks me.

That NCBI one shows C.bot being killed at temperatures under 100 celsius which doesn't contradict anything I said. See table 5. I never said all of them were to support my point of 100 c being fine. I posted ALL of those for people, if they wish, to educate themselves on the whole process, hence a couple textbooks, how the TDT in canning works, etc...


Is there a difference in heat-resistance between the bacteria and the spores?


Yes. The bacteria dies easier. But, the 12d process, and the f-values are formulated regarding the death of the spores.




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