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Decimal Reduction Time (D-value) Determination

Calculates the time required at a constant temperature to achieve a 90% reduction in a microbial population based on first-order death kinetics.

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1. Define Input Parameters

2. Engineering Output

Initial Log Population (LogN0)
- log10
Final Log Population (LogNt)
- log10
Log Reduction (DeltaLog)
- log10
Decimal Reduction Time (DT)
- min

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Context & Assumptions

The D-value is a fundamental parameter in thermal process engineering used to design safe sterilization cycles for food and pharmaceuticals. It quantifies the heat resistance of specific microorganisms at a target temperature to ensure commercial sterility.

Understand the Engineering Principles

Review the step-by-step derivations, typical industrial limits, and scale-up rules.

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