Term: dilution rate, D
https://doi.org/10.1351/goldbook.D01740

Definition:
The ratio of the ingoing volume flow rate (dV/dt) and the culture volume (V). In continuous fermentation, a measure of a rate at which the existing medium is replaced with fresh medium, D is the reciprocal of the hydraulic retention time (HRT).

Related Terms:
1) volume flow rate (http://doi.org/10.1351/goldbook.V06642).
2) fermentation (http://doi.org/10.1351/goldbook.F02337).

Source: PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 152 (https://doi.org/10.1351/pac199264010143)

Citation: 'dilution rate, D' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.D01740

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