The interpretation of the several variables that contribute to defining milk quality is difficult due to the high degree of
correlation among them. In this case, one of the best methods of statistical processing is factor analysis, which belongs
to the multivariate groups; for our study this particular statistical approach was employed.
A total of 1485 individual goat milk samples from 117 Girgentana goats, were collected fortnightly from January to July,
and analysed for physical and chemical composition, and clotting properties. Milk pH and tritable acidity were within the
normal range for fresh goat milk. Morning milk yield resulted 704 ± 323 g with 3.93 ± 1.23% and 3.48±0.38% for fat
and protein percentages, respectively. The milk urea content was 43.70 ± 8.28 mg/dl. The clotting ability of Girgentana
milk was quite good, with a renneting time equal to 16.96 ± 3.08 minutes, a rate of curd formation of 2.01 ± 1.63 min-
utes and a curd firmness of 25.08 ± 7.67 millimetres.
Factor analysis was performed by applying axis orthogonal rotation (rotation type VARIMAX); the analysis grouped the
milk components into three latent or common factors. The first, which explained 51.2% of the total covariance, was
defined as “slow milks”, because it was linked to r and pH. The second latent factor, which explained 36.2% of the total
covariance, was defined as “milk yield”, because it is positively correlated to the morning milk yield and to the urea con-show abstract
