Scuola di Scienze Agrarie, Forestali, Alimentari ed Ambientali, Università della Basilicata, Via dell'Ateneo Lucano, 10-85100 Potenza, Italy.
J Anim Sci. 2013 Dec;91(12):5885-93. doi: 10.2527/jas.2012-6220. Epub 2013 Oct 14.
The purpose of the present study was to assess the effect of grazing on meat quality of young Podolian bulls by using 6 free-ranging (FR) and 6 confined (CON) animals slaughtered at 18 mo of age (Exp. 1). A second experiment (Exp. 2) was performed the subsequent year where the age at slaughter was 15 mo of age (6 animals/group). Quantitative descriptive sensory analysis, water-holding capacity (WHC; thawing, centrifugation, and cooking losses), and shear force (only in Exp. 2) were evaluated on LM, aged 8 d. Both experiments showed that CON animals produced beef with greater overall beef flavor (P < 0.01 and P < 0.05 in Exp. 1 and 2, respectively) and odor intensities (P < 0.10 and P < 0.05 in Exp. and 1 and 2, respectively) and increased malondialdehyde contents (P < 0.01 and P < 0.05 in Exp. 1 and 2, respectively). In Exp. 2 beef from FR bulls showed higher sensory tenderness as compared with CON bulls (P < 0.05) and a lower shear force (P < 0.05). In Exp. 1, beef obtained from FR bulls showed lower centrifugation and greater thawing losses compared with samples from bulls from group CON (P < 0.05) whereas rearing system did not affect any WHC variables in Exp. 2. The results obtained from the 2 experiments were generally consistent. The different results occasionally observed (e.g., sensory tenderness and WHC) is attributed to the different ages at slaughter used in the 2 experiments (18 and 15 mo). In particular, at an earlier age at slaughter (15 mo) the effect of FR on meat quality was beneficial on sensory tenderness and mechanical properties. Therefore, given the additional costs of maintaining the bulls for another 3 mo when slaughtered at 18 mo of age, a reduced age at slaughter of FR bulls may be suggested to avoid the decrement of herbage mass availability inducing the consumption of high amounts of concentrate.
本研究的目的是通过使用 6 头自由放养(FR)和 6 头限制饲养(CON)的公牛,评估放牧对年轻的波德代公牛的肉质的影响,这些公牛在 18 月龄(实验 1)时被屠宰。第二年进行了第二个实验(实验 2),屠宰年龄为 15 月龄(每组 6 头)。在第 8 天的 LM 上进行了定量描述性感官分析、水分保持能力(解冻、离心和蒸煮损失)和剪切力(仅在实验 2中)的评估。两个实验均表明,CON 动物生产的牛肉具有更高的总体牛肉风味(实验 1 和 2 分别为 P < 0.01 和 P < 0.05)和气味强度(实验 1 和 2 分别为 P < 0.10 和 P < 0.05),且丙二醛含量增加(实验 1 和 2 分别为 P < 0.01 和 P < 0.05)。在实验 2 中,与 CON 公牛相比,FR 公牛的牛肉表现出更高的感官嫩度(P < 0.05)和较低的剪切力(P < 0.05)。在实验 1 中,与来自 CON 组公牛的样本相比,FR 公牛的牛肉的离心和解冻损失较低(P < 0.05),而在实验 2 中,饲养系统没有影响任何水分保持能力变量。两个实验的结果基本一致。偶尔观察到的不同结果(例如感官嫩度和水分保持能力)归因于两个实验中使用的不同屠宰年龄(18 和 15 月龄)。特别是在较早的屠宰年龄(15 月龄)时,FR 对肉品质的影响有利于感官嫩度和机械性能。因此,鉴于在 18 月龄时屠宰时再额外饲养公牛 3 个月的成本,建议降低 FR 公牛的屠宰年龄,以避免由于牧草质量减少而导致大量浓缩饲料的消耗。