Hi ss!
The time and temperature combine to kill the target bacteria, and depend on the media/product content bacteria.
Fa (Fa=1=65oC@1 min): for normal bacteria and YM with product (PH<4.6; having CO2)
Fb (Fa=1=85oC@1 min): for normal bacteria and YM with product (PH<4.6; non CO2)
Fo (Fa=1=121,1oC@1 min): for Mesophillic and Thermophillic with product (PH>4.6)
However, depend on kind of Meso/Thermophillic to apply Fo value:
EX:
Clos.botulinum Fo 4.5,
Bac.sterothermophillic Fo = min 7 to 8 (Recommend this is Fo= min 15 for safety )
But this is just Lab testing. If we want to apply for commercial run, we must find D value and Fo can be used. Because Fo for commercial run depend on kind of bacteria, quantity bacteria, safety accept (1/10000 unit or 1/100000, ...)
Fa, Fb, Fo is define clear with Japanese document
Regards,
Dinh