2.5. Prato cheese manufacture
For the manufacture of Prato cheese, 20 L milk (Atilatte e
Fazenda Atibainha, Atibaia, SP) were pasteurized (63 C/30 min)
and cooled to 35 C. Then, 1% type “O” starter culture was added
(Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris),
followed by calcium chloride (250 ppm), annatto dye
(80 ppm) and coagulant (Ha La 1175, Christian Hansen) in amount
sufficient to coagulate the milk in 35 min. After 35 min, the gel
was cut into 1 cm cubes, and slow stirring was applied for 15 min.
After a 5 min-rest, the whey was partially drained (30% initial
volume of milk), and hot water (80 C) was added for the cooking
stage up to 42 C at a rate of 1 C/3 min. Then, the whey was
partially drained, and 1% cell concentrate of L. acidophilus was
added. The remaining whey was drained, the curd was distributed
into 0.5 kg rectangular plastic molds and pressed (30 psi/30 min;
50 psi/90 min) at room temperature using a vertical pneumatic
press. After pressing was completed, the cheeses remained for a
period of 5 h at room temperature for fermentation. Then, the
cheeses were placed in brine (20% salt) for 10 h at 5 C. The
cheeses were dried for 48 h at 12 C and vacuum packed. Then,
they were stored at 12 C and subjected to microbiological evaluation
after 1 day of manufacture.