The effects of lactose on calcium phosphate precipitation
Calcium phosphate, as the main insoluble component of milk and dairy products, has been always of interest in dairy research. When milk is concentrated by evaporation or reverse osmosis, the calcium phosphate and lactose become supersaturated. The main objective of this work was to be able to experimentally ascertain the effect of lactose on calcium phosphate precipitation, especially at higher concentrations. The experiments were carried out at 23 °C with various concentrations of calcium and phosphate solutions without and with 9.5% w/w lactose. pH was a key factor to determine the amount of calcium phosphate precipitation. Zetasizer analysis showed that lactose strongly influenced the calcium phosphate solution by forming nanoparticles with a size of about 1 nm. The role of lactose in enabling the formation of nanoparticles was previously unknown but is likely to be an important property of milk.