GIFSQ Tools · Module 10 — Packaging & Shelf-Life · Tool 195 of 500
Predict shelf life at a new storage temperature from the life at a known temperature and the activation energy, using the Arrhenius equation.
Try sample values — fills the form with the worked example below.
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Rate ratio (k₂/k₁)
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Shelf life at new temperature (days)
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Change (%)
Equation: k₂/k₁ = exp[−Ea/R × (1/T₂ − 1/T₁)], with Ea in J/mol, R = 8.314 J/mol/K and T in kelvin. Shelf life at T₂ = shelf life at T₁ ÷ (k₂/k₁). Change (%) = (life₂ − life₁) ÷ life₁ × 100.
Method: Arrhenius shelf-life model: the spoilage rate follows the Arrhenius temperature dependence, and shelf life is taken as inversely proportional to that rate.
Assumptions: one dominant spoilage reaction with a constant activation energy; the reaction mechanism does not change between the two temperatures.
Limitations: the model fails when the spoilage mechanism changes with temperature (for example, freezing, fat melting or a different microbe taking over); it is an estimate, not a measured shelf life.
Rounding: rate ratio to 2 decimal places; shelf life to 2 decimal places; change to 2 decimal places; intermediates unrounded.
This is a calculation aid, not a laboratory report — confirm against your accredited method before citing a value.
Method: Arrhenius shelf-life model: the spoilage rate follows the Arrhenius temperature dependence, and shelf life is taken as inversely proportional to that rate.
Assumptions: one dominant spoilage reaction with a constant activation energy; the reaction mechanism does not change between the two temperatures.
Limitations: the model fails when the spoilage mechanism changes with temperature (for example, freezing, fat melting or a different microbe taking over); it is an estimate, not a measured shelf life.
Rounding: rate ratio to 2 decimal places; shelf life to 2 decimal places; change to 2 decimal places; intermediates unrounded.
This is a calculation aid, not a laboratory report — confirm against your accredited method before citing a value.
Worked example: Ea 80 kJ/mol, 365 days at 25 °C, warmed to 35 °C: k₂/k₁ = exp[−80,000/8.314 × (1/308.15 − 1/298.15)] = 2.85; shelf life = 365 ÷ 2.85 = 128.07 days (−64.91%).
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Typical activation energies: 50–100 kJ/mol for chemical spoilage; use the value measured for your own product where possible. Tool 195 of 500 — GIFSQ
