Foodstuff Thermal Diffusivity

Overview

Engineering reference data for Foodstuff Thermal Diffusivity 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

Applying the Formula

The fundamental relationship for thermal diffusivity ($\alpha$) connects it to three other key material properties:

$\alpha = \frac{k}{\rho \cdot C_p}$

This equation shows that diffusivity is directly proportional to thermal conductivity ($k$) and inversely proportional to the product of density ($\rho$) and specific heat capacity ($C_p$). A material with high $\alpha$ will respond rapidly to temperature changes, which is a critical factor in food processing for predicting heating/cooling rates, cooking times, and ensuring food safety.

Interactive Charts

References

• Original Source