aliment ph

Overview

Engineering reference data for Food PH in food bio.

Key Formulas

pH

$pH = -\log_{10}[H^+]$

Measure of acidity in food.

Water Activity

$a_w = \frac{P}{P_0}$

Ratio of vapor pressure of food to pure water.

Thermal Death Time

$\log\frac{N_0}{N} = \frac{t}{D}$

Microbial reduction during heating.

Q10 Temperature Coefficient

$Q_{10} = \left(\frac{k_2}{k_1}\right)^{10/(T_2-T_1)}$

Rate change per 10°C temperature increase.

Variables

Symbol	Description	Unit
$pH$	Acidity level	—
$a_w$	Water activity	—
$N$	Microbial count	CFU
$D$	Decimal reduction time	min
$Q_{10}$	Temperature coefficient	—

References

• Original Source