Impact of the ageing process on the intensity of post mortem proteolysis and tenderness of beef from crossbreeds

Abstract

The aim of the study was the evaluation of the effect of ageing on the extent of myofibrillar proteins degradation and tenderness of beef in different crossbreeds, BB × HF and SM × HF, from which the musculus semitendinosus was obtained. The pH value, basic composition of meat, and colour parameters were determined on the 3 rd d post mortem. The Warner Bratzler shear force and the extent of protein degradation were evaluated in regard to the effect of ageing time. Meat of BB × HF crossbreed had a lower amount of intramuscular fat and higher protein content (P ≤ 0.05). The shear force decreased with ageing time in the case of both crossbreeds. However, the highest values were noted in SM × HF crossbreed on days 3 and 7 of ageing. The differences in proteolysis of myofibrillar proteins and polypeptides, determined by SDS-PAGE electrophoresis, were observed between crossbreeds and the ageing time. A significant decrease in desmin and increased levels of 49-46 kDa and 32-27 kDa polypeptides (products of proteolytic degradation) were observed with an increasing ageing time. In addition, the rate of increase in the amount of 32-27 kDa polypeptides was more significant in BB × HF crossbreed. The data obtained showed that tenderness and the extent of protein degradation are associated with ageing process and animals' genotype.

Effects of selected myofibrillar protein activities on beef tenderization process based on electrophoretic analysis

“…By electrophoretic separation of muscle proteins and the use of monoclonal antibodies for specifically tracking troponin T, it was proved that troponin T significantly decreased with aging time ( p < .001), as presented in Table . The results obtained concur with earlier studies by Sun et al () and Moczkowska, Półtorak, and Wierzbicka (). The most significant drop in the level of troponin T occurred in both ST and PM from the 2nd to 7th days of aging, when the activity decreased by 17.30 and 20.42%, respectively.…”

“…By electrophoretic separation of muscle proteins and the use of monoclonal antibodies for specifically tracking troponin T, it was proved that troponin T significantly decreased with aging time (p < .001), as presented in Table 3. The results obtained concur with earlier studies by Sun et al (2014) and Moczkowska, P ołtorak, and Wierzbicka (2015).…”

The effect of ageing on changes in myofibrillar protein in selected muscles in relation to the tenderness of meat obtained from cross‐breed heifers

“…() who also showed strong positive correlation ( r > 0.75, P < 0.01). The decrease in desmin and Tn‐T and increase in polypeptides: 30 and 46 kDa in all analysed muscles (but at varying rates) indicated that the postmortem proteolysis of myofibrillar proteins is strictly related to the ageing process, which is in agreement to previous studies (Huff Lonergan et al ., ; Moczkowska et al ., ).…”

Influence of post-mortem muscle glycogen content on the quality of beef during aging

“…The measurement of the shear force value was performed with Instron 5965 (Instron, Norwood, USA), equipped with a 500 N head, Warner-Bratzler measurement unit, and Bluehill® 2 software. Knife speed of 200 mm·min -1 was used for measurement purposes (16).…”