Composition of Ragusano cheese during aging

Ragusano cheese is a brine-salted pasta filata cheese. Composition changes during 12 mo of aging were determined. Historically, Ragusano cheese has be en aged in caves at 14 to 16 degrees C with about 80 to 90% relative humidi ty. Cheeses (n = 132) included in our study of block-to-block variation wer e produced by 20 farmhouse cheese makers in the Hyblean plain region of the Province of Ragusa in Sicily. Mean initial cheese block weight was about 1 4 kg. The freshly formed blocks of cheese before brine salting contained ab out 45.35% moisture, 25.3% protein, and 25.4% fat, with a pH of 5.25. As re sult of the brining and aging process, a natural rind forms. After 12 mo of aging, the cheese contained about 33.6% moisture, 29.2% protein, 30.0% fat , and 4.4% salt with a pH of 5.54, but block-to-block variation was large. Both soluble nitrogen content and free fatty acid (FFA) content increased w ith age. The pH 4.6 acetate buffer and 12% TCA-soluble nitrogen as a percen tage of total nitrogen were 16 and 10.7%, respectively, whereas the FFA con tent was about 643 mg/100 g of cheese at 180 d. Five blocks of cheese were selected at 180 d for a study of variation within block. Composition variat ion within block was large; the center had higher moisture and lower salt i n moisture content than did the outside. Composition variation within block s favored more proteolysis and softer texture in the center.