| Resumo: | Changes in the main physicochemical and biochemical characteristics of bovine, ovine and caprine milk cheeses manufactured with aqueous extracts of flowers of Cynara cardunculus were studied throughout ripening (0 – 68 days). At the end of ripening the pH in the centre was (mean ± ISD) 5.05±0.07, 5.15±0.21 and 4.91±0.07 for bovine, ovine and caprine milk cheeses, respectively; whereas the pH at the top of the cheese was 5.21±0.09, 5.44±0.12 and 5.12±0.07, respectively; the moisture content values of bovine, ovine and caprine milk cheeses were 37.68±2.32, 40.23±4.34 and 45.73±1.44%, respectively; the NaCl content values were 4.00±0.43, 4.00±0.56 and 4.08±0.58 (%TS); the fat content values were 41.01±5.32, 63.60±7.80 and 45.14±9.14 (%TS); the protein content values were 28.96±1.84, 22.89±2.37 and 30.02±1.22 (%TS); the water-soluble nitrogen values were 32.91±1.76, 46.44±1.86 and 48.72±1.08 (%TN); the values of nitrogen soluble in trichloroacetic acid were 10.25±1.93, 10.41±2.91 and 7.25±0.84 (%TN); the values of nitrogen soluble in phosphotungstic acid were 1.50±0.18, 1.87±0.65 and 1.38±0.32 (%TN); finally, the free amino acid content values were 21.33±5.34, 17.51±5.08 and 23.93±4.80 μM equivalents of leucine. Urea-polyacrylamide gel electrophoresis of water-insoluble fractions from cheeses indicated high degrees of proteolysis of αs1-casein in bovine cheeses and more extensive proteolysis of the αs-casein region in caprine than in ovine cheeses, but a moderate degree of proteolysis of β-casein in all types of cheese; electrophoregrams of the water-soluble fraction displayed increasing numbers of bands throughout ripening, an observation that is consistent with the increase in the ratio of water-soluble nitrogen to total nitrogen.
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