Firmness and melting properties of Requeijao cheese

Requeijao cheese, a typical spreadable processed cheese, was prepared from a cheese base obtained by ultrafiltration of pre-acidified milk at pH 5.2 o r 5.7, with and without added whey protein concentrate (WPC) and emulsifyin g salt Joha S9 or S10. At both pH levels there was complete retention of th e fat and almost complete retention of the protein. At pH 5.2 there was a l ower retention of Ca and P. The addition of WPC increased the firmness of t he cheeses. The type of emulsifying salt used also had a significant effect on firmness. The interaction between ultrafiltration pH and the addition o f WPC decreased the melting capacity of the cheeses, the greatest reduction being observed when the milk was pre-acidified to pH 5.2.