✅ Quality control
Also known as: QC
Fat, protein, bacteria, antibiotics, acidity.
Quality control means testing milk in the dairy plant's laboratory. Several things are checked. Fat and protein decide how much the milk is worth and what products can be made from it. Fat is often measured with the Gerber method. The bacteria count shows how cleanly the cow was milked and how well the milk was cooled. Somatic cells are mostly the cow's immune cells. If there are more than 400,000 per millilitre, the cow most likely has mastitis, an udder infection.
Other things are checked too. Antibiotics: milk containing them is rejected. The freezing point: normal milk freezes between −0.54 and −0.59 °C, while milk watered down freezes closer to zero. Acidity (pH around 6.7) and an alcohol test show whether the milk can stand strong heating.
The EU sets limits for raw cow's milk: no more than 100,000 germs per millilitre (counted at 30 °C) and no more than 400,000 somatic cells. These are averages over two and three months. If they are exceeded, the farm must fix the problem and tell the authorities. A lab technician also tests the finished products before they go on sale.
How it connects to milk
✅ Quality control → kind of → 🏭 Milk processing at the dairy plant → kind of → 🥛 Milk
Links
- Where it happens
- 🔬 Laboratory
- Previous step
- 🔄 Milk reception
- Next step
- 🔄 Separation
- Who works with it
- 🧑🔬 Laboratory technician, 🧑🔬 Dairy technologist
- Part of
- 🏭 Milk processing at the dairy plant
- Wine and milk
- 🍷 Wine tasting
Frequently asked questions
How can you tell if milk has been watered down?
By its freezing point. Normal milk freezes at about −0.54 to −0.59 °C, and added water moves this point closer to zero.
What are somatic cells in milk?
They are mostly the cow's immune cells. There are always a few, but more than 400,000 per millilitre is a sign of udder inflammation.
What to read next
- 🧑🔬 Laboratory technician — Tests milk in a lab: under EU rules raw cow's milk may hold no more than 400,000 somatic cells per millilitre, and bacteria and antibiotics are checked too.
- 🔄 Milk reception — The first stage of handling milk at the dairy: checking, measuring volume, cooling below +4 °C and storing in silos of 50,000–500,000 litres.
- 🍷 Wine tasting — Careful tasting: looking at the colour, smelling, tasting and judging.
- 🧑🔬 Dairy technologist — A specialist who selects recipes and milk-processing settings at a dairy plant, including pasteurization at 72 °C.
- 🔄 Separation — Splitting milk into cream and skim milk in a centrifugal separator at 55–65 °C; the skim milk keeps only 0.04–0.07% fat.
Similar
🔄 Standardization · 🔄 Churning · 🔄 Slow baking · 🔄 Separation · 🌡️ UHT processing · 🔄 Drying
Sources
- Tetra Pak Dairy Processing Handbook: Collection and reception of milk
- Regulation (EC) No 853/2004, Annex III, Section IX (raw milk)