Yoghurt Culture Inoculation Calculator

Work out yoghurt culture inoculation instantly with clear inputs, formula shown and shareable results.

About Yoghurt Culture Inoculation Calculator

Bulk starter is dosed at 1-3% of the milk volume, while direct vat set cultures are dosed in units per 1000 litres according to the supplier's specification. Bulk starter is cheaper per litre but requires its own propagation, hygiene control and phage management; DVS removes that risk entirely.

Formulas

Bulk starter

Starter volume = milk volume x inoculation rate %

Direct vat set

DVS units = milk volume x units per 1000 L / 1000

Worked example

With the default values below, Yoghurt Culture Inoculation Calculator returns Inoculum Required of 20.0000. Change any input above and every figure here is recalculated in your browser.

Inputs used

Milk Volumeminimum 0 L: 1,000 L
Inoculation Rateaccepts 0.001–10 %: 2 %
Culture Formone of Bulk starter, Direct vat set (DVS): Bulk starter
DVS Units Per 1000 Lminimum 0 units: 1 units

Results

Inoculum Required: 20.0000
Bulk Starter Volume Equivalent: 20.000
DVS Units Required: 1.0000
Bulk Starter Milk To Prepare: 21.000

Step by step

1Values used
2Bulk starter
3Direct vat set
4Inoculum Required= 20.0000
5Bulk Starter Volume Equivalent= 20.000
6DVS Units Required= 1.0000
7Bulk Starter Milk To Prepare= 21.000

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Why does inoculation rate matter?

It sets the fermentation time and therefore the acid development curve. Higher rates ferment faster but can give a coarser gel and less flavour development; lower rates risk phage and contaminant overgrowth.

What is bacteriophage and why does it matter?

Viruses that lyse starter bacteria, causing slow or failed fermentation. Rotating strains, strict bulk starter hygiene and phage-inhibitory media are the controls; DVS greatly reduces exposure.