Acidified fruit milk drinks

Fruit milk drinks

Casein is a milk protein that forms a colloidal solution and is dispersed throughout the milk and is not truly dissolved. The Casein micelles have a - negative charge that causes them to repel each other. This is the reason why fresh milk is liquid and not curdled.

The addition of fruit juice will neutralise the charge of the casein and cause the casein micelles to cling together and the milk to curdle. The acid in the fruit causes the Casein to lose its negative charge and become more neutral. Pectin is then added because of its ability to retain its negative charge. The difference in charge makes it possible for the pectin and the casein to link and prevent the curdling of the milk. We could not make commercial healthy milk drinks with fruit without the use of gelling agents.