✅ Quality control

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.