tsscherzo

Hello

I'm a Greenhorn to this group but I hope anyway that you can help me.
At the moment I deal with yeast (esp. Saccharomyces cerevisiae) and I
have quite a big problem to get any data about heat inactivation of
their Ascospores.

Does anybody know a source of D- and z-Values for yeast Spores . It
seems to be very hard to get anything about this. What about the
dependence on pH and aw for sporulation, inactivation?

I just read somwhere in the net that it's necessary to heat Spores
from S. cerevisiae for 20 min. at 120°C, can this be true?

Thanks for your help

Thomas

tsscherzo

Hello

I'm a Greenhorn to this group but I hope anyway that you can help me.
At the moment I deal with yeast (esp. Saccharomyces cerevisiae) and I
have quite a big problem to get any data about heat inactivation of
their Ascospores.

Does anybody know a source of D- and z-Values for yeast Spores . It
seems to be very hard to get anything about this. What about the
dependence on pH and aw for sporulation, inactivation?

I just read somwhere in the net that it's necessary to heat Spores
from S. cerevisiae for 20 min. at 120°C, can this be true?

Thanks for your help

Thomas

reg

The spores don't have D and Z values, do they? I think only the vegetative cells.


I'm looking for this info too and if I find it I'll post it.

--
Reg email: RegForte (at) (that free MS email service) (dot) com

n10

Hello

Try these


http://www.apha.org/media/foodschapter.pdf

My own work with Saccharomyces mixed populations in ph 4.6 buffer gave 5.3
log reductions in 12 seconds at 72'c

The temp/time you report probabley refers to Byssochamlys species (
Ascomycetes) which form heat resistant spores ; here

http://www.vency.com/webPASTEURIZATION.html

Probaley this willanswer all your quiries

http://vm.cfsan.fda.gov/~comm/ift-over.html


Best N10

reg

This is very good information. Thank you.

--
Reg email: RegForte (at) (that free MS email service) (dot) com