Food Microbiology
z-value
The temperature increase required to reduce the D-value by a factor of ten — the slope of the thermal death time curve.
Real-life application
Used alongside D-value by canning engineers to predict how a sterilisation process needs to change if the processing temperature is adjusted.
Related terms
D-value
Food MicrobiologyThe time at a given temperature required to destroy 90% of a microbial population — one log reduction.
F-value
Food MicrobiologyThe total lethality of a heat process expressed as equivalent minutes at a reference temperature. F0 is the reference at 121.1 °C with z = 10 °C.
Q10
Quality & SensoryThe factor by which a reaction rate changes for a 10 °C rise in temperature.
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