Framework for life cycle assessment of livestock production systems to account for the nutritional quality of final products

Abstract

Life cycle assessment (LCA) is widely regarded as a useful tool for comparing the environmental impacts of multiple livestock production systems. While LCA results are typically communicated in the form of environmental burdens per mass unit of the end product, it is increasingly becoming recognized that the product quality also needs to be accounted for to truly understand the value of a farming system to society. To date, a number of studies have examined environmental consequences of different food consumption patterns at the diet level; however, few have addressed nutritional variations of a single commodity attributable to production systems, leaving limited insight into how on‐farm practices can be improved to better balance environment and human nutrition. Using data from seven livestock production systems encompassing cattle, sheep, pigs, and poultry, this paper proposes a novel framework to incorporate nutritional value of meat products into livestock LCA. The results of quantitative case studies demonstrate that relative emissions intensities associated with different systems can be dramatically altered when the nutrient content of meat replaces the mass of meat as the functional unit, with cattle systems outperforming pig and poultry systems in some cases. This finding suggests that the performance of livestock systems should be evaluated under a whole supply chain approach, whereby end products originating from different farm management strategies are treated as competing but separate commodities.

Assessing the environmental impact of ruminant production systems

“…As discussed elsewhere in this book, one of the most common methods to evaluate environmental footprints of farming systems is life cycle assessment (LCA). Although LCA itself is suitable for and indeed adopted by a wide range of industries far beyond agriculture, what separates agriculture, and in particular pasture-based ruminant production systems, is the high degree of uncertainties associated with physical, chemical and biological processes that underpin production (McAuliffe et al, 2018a). In the presence of uncertainties, point-estimates provided by LCA models are unlikely to be informative enough to offer robust policy implications (Chen and Corson, 2014); when this is the case, the resultant environmental burdens must be expressed in the form of probability distributions and interpreted accordingly (McAuliffe et al, 2017).…”

The ‘Palo a Pique’ Long-Term Research Platform: First 25 Years of a Crop–Livestock Experiment in Uruguay

“…In this way, the original pasture-crop rotations at the 'Palo a Pique' LTE have become a platform for new studies that model system effects on the environment using life cycle assessment (LCA) methodology [54]. Studies employing LCA approaches estimate pollution-production ratios as their primary outputs (i.e., kg CO 2 e per unit of food produced), where farming systems that have low scores are determined to be more desirable, although nutrient quality and the entire supply chain must also be considered [53,55,56]. Table 1 shows a simplified prediction of environmental KPIs in the four systems of the 'Palo a Pique' LTE recommended by Kanter et al [31] for developing transformation pathways in Uruguay's beef sector.…”

Review: Analysis of the process and drivers for cellular meat production

“…Meat is well known to be a good source of high-quality protein, including essential amino acids, Vitamin B 12 , iron, zinc and selenium. For example, from 100 g of pork, the consumer derives~37% of their daily protein requirements, 67% of their daily Vitamin B 12 requirements and 15% to 16% of their selenium and zinc requirements (McAuliffe et al, 2018). Thus in order to compare foods, it is important to compare them not only on a nutrient basis but also on a nutrient bioavailability and gut health basis.…”