ABSTRACT

Beef meat, one of the more environmentally costly animal-based foods, can be produced in two general ways, as the main product on specialised farms or as a co-product on dairy farms. In this study, two cases (a semi-confinement dairy farm (A) and a pasture-based dairy farm (B)) have been analysed by means of LCA to evaluate the environmental impacts associated with the coproduction of beef meat. In both cases, purchased feed production was found to be the main cause of environmental impacts in most of the categories considered. Additionally, cow emissions to air were the main contributor for the global warming category. Comparing the two dairy systems, notably lower environmental impacts were obtained for B in 13 of the 18 categories analysed. Regarding CF, 8.10 and 8.88 kg CO₂eq/kg LW were obtained for A and B, respectively. These CF values were within the wide range found in the literature for beef meat (1.2–42.6 kg CO₂eq/kg LW). Beef calves and cull cows are an important output of dairy farming, so that coproduction enables milk and meat with lower CF and associated environmental impacts to be obtained. In addition, the variability of the data found in literature and the lack of LCA studies based on real data for beef meat coproduced on dairy farms evidence the importance of in-depth study of this interesting topic.

摘要

牛肉是环境成本较高的动物性食品之一，可以通过两种一般方式生产，作为专业农场的主要产品或作为奶牛场的副产品。在本研究中，通过 LCA 分析了两个案例（半封闭奶牛场 (A) 和牧场奶牛场 (B)），以评估与牛肉联合生产相关的环境影响。在这两种情况下，购买的饲料生产被发现是大多数所考虑类别中环境影响的主要原因。此外，奶牛排放到空气中是导致全球变暖类别的主要原因。比较两种乳制品系统，在所分析的 18 个类别中的 13 个类别中，B 的环境影响明显较低。关于 CF，8.10 和 8.88 kg CO ₂分别获得了 A 和 B 的 eq/kg LW。这些 CF 值在牛肉文献中发现的广泛范围内（1.2–42.6 kg CO ₂ eq/kg LW）。肉牛犊和淘汰牛是奶牛养殖的重要产出，因此联合生产能够获得具有较低 CF 和相关环境影响的牛奶和肉类。此外，文献中数据的可变性以及基于奶牛场联合生产的牛肉真实数据的 LCA 研究的缺乏证明了深入研究这一有趣主题的重要性。