A Milk Test Determines Whether It Can Become Cheese in São Paulo

At a property in Salto de Pirapora, in São Paulo state, the first assessment takes place before mechanically milking a herd of 33 Jersey cows. The black-cup test is a visual examination of the milk’s thickness and is used to identify problems before the milk reaches the dairy plant, according to veterinarian Isabelly Dornelas, who oversees the herd.

The animals are handled in a way intended to limit stress before milking. Their feed includes maize silage and grains, which help maintain the fat and protein levels used to assess the raw material for dairy products. The herd is milked twice a day and produces about 500 litres in total.

After collection, the milk is chilled to 4°C. It remains at that temperature while being transported to the factory, where further checks are carried out before processing.

A dairy plant in the area receives milk from eight local producers and processes roughly 3,000 litres each day. Its output includes fresh cheese, meia-cura cheese and Estrada de Ferro, a specially matured cheese that has received seven medals in national competitions.

At the plant, pasteurisation and the absence of bacterial contamination are among the controls applied to each batch. If a problem is found, the entire batch is discarded rather than being used in finished products.

Quality testing is also taught at universities in Sorocaba. Students of food engineering and pharmacy practise identifying the main forms of fraud affecting the dairy sector and learn to choose the appropriate analysis at different production stages. The most common form described is economic fraud, in which water or whey is added to increase the volume of milk. Eduarda Gonçalves, coordinator of the food-engineering course, said that testing determines whether milk delivered to the factory is suitable for consumption.