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Adulteration

Milk and dairy product testing

Milk testing covers composition, adulteration and microbiological quality. Composition — fat and solids-not-fat — decides commercial value and whether the milk meets its declared type. Adulteration screens look for added water, neutralisers, urea, detergent and starch. Microbiology tells you how it was handled after milking.

Three layers
Composition · adulteration · micro
Sample needed
500 ml milk, 200 g paneer
Cold chain
Essential — send chilled
Common use
Procurement disputes, FSSAI file

What we test on milk and dairy

Compositional standards differ by milk type — cow, buffalo, toned, double toned and standardised each have their own minimum fat and SNF. We report against the type you declare.

ParameterCategoryWhat it tells you
FatCompositionCommercial value and type conformity
Solids-not-fat (SNF)CompositionThe other half of type conformity
ProteinCompositionNutritional declaration
LactoseCompositionAuthenticity and nutrition
Freezing pointAdulterationThe reliable test for added water
Titratable acidityQualitySouring and cold chain failure
NeutralisersAdulterationSoda added to mask souring
UreaAdulterationAdded to inflate apparent SNF
DetergentAdulterationUsed to emulsify added fat
Starch and maltodextrinAdulterationBulking agents
MBRTMicroRapid bacterial load screen
Standard plate countMicroHygiene at milking and handling
ColiformsMicroPost-pasteurisation contamination

What to send us

Quantity
500 ml of milk, or 200 g of paneer, khoa, curd or sweets
Container
Clean bottle filled nearly full for milk; sterile pouch for solid dairy if not in retail packaging
Hold time
Within a few hours, chilled at 4 °C. Milk left warm will fail on acidity and microbiology regardless of its original quality
Full collection instructions →

Added water is the common one

In procurement disputes, dilution is far more common than exotic adulterants — and it is also the one most often missed, because fat and SNF can be brought back into range by adding solids after adding water. Freezing point depression is the test that catches it, because it responds to dilution regardless of what was added afterwards. If you buy loose milk at volume, that is the parameter to put on your incoming check.

Questions about this test

Lactometer reading looks fine. Is the milk unadulterated?

Not necessarily. A lactometer measures density, which can be manipulated — adding water lowers it and adding solids raises it back. Freezing point and a compositional analysis together are much harder to fool.

Can you test sweets and paneer?

Yes. For sweets the usual concerns are the fat used, starch as a bulking agent, synthetic colours and microbiological quality, especially for khoa-based sweets in warm weather.

Why did my pasteurised milk fail on coliforms?

Pasteurisation destroys coliforms, so their presence in a pasteurised product points at contamination after the heat step — filling equipment, packaging or handling. That is a plant hygiene investigation, not a pasteurisation one.

Request this testAsk on WhatsAppUpdated 16 September 2026