The effects of breed and aging time (1, 7, 14, 21 d)were evaluated on physical meat properties and on sarcoplasmic
protein changes in 24 young bulls from Romagnola × Podolian, Podolian and Friesian breeds. Aging affects
lightness showing an increase in all breeds while changes in redness varied according to the breed. Podolian
breed showedmeatwith the darkest and the reddest color and the lowest drip loss compared to the other breeds.
Extending aging to 21 d reduced drip loss from meat. SDS-PAGE and 2DE showed that many changes in the sarcoplasmic
proteins occurred among breeds and during aging. During post-mortem some sarcoplasmic proteins
decline in intensity after 21 d highlighting that theywere susceptible to aging. Protein identification andwestern
blotting showed the presence ofmyosin light chains, Troponin T and tropomyosin proteins during aging, suggesting
a degradation of myofibers and a more intense proteolysis especially in the Podolian breed.