Uncovering the environmental burden of hops: a spatially resolved agricultural LCA for modern beer supply chains

Abstract

Purpose With the expansion of microbreweries and rising demand for craft beer, attention has increasingly turned to hops (Humulus lupulus), a key brewing component that remains understudied from an environmental impact perspective. This study assesses the environmental burdens of hop production in a new French growing region, comparing organic and conventional systems under contrasting yield levels, and addressing whether GIS-based nutrient emission modelling improves the representation of spatial variability in agricultural Life Cycle Assessment (LCA).

Methods An attributional cradle to farm-gate LCA was conducted for hop production systems located in Aquitaine. 1 kg of dried hop cones before pelletization was chosen as the Functional Unit (FU). The perennial cycle was represented over a 20-year lifespan by distinguishing establishment and productive phases and normalizing total impacts by cumulative production. Impact categories included Global Warming (GW), Terrestrial Acidification (TA), Terrestrial and Freshwater Ecotoxicity (TET - FET), Freshwater Eutrophication for nitrogen (FEn) and phosphorus (FEp), and Water Scarcity (WS). Nutrient leaching was estimated with InVEST Nutrient Delivery Ratio (NDR) model and compared with conventional approaches.

Results and discussion Hop production was found to carry considerable environmental burdens, mainly driven by fertilization intensity, fuel-related field operations, and energy use during kilning. Organic low-yield systems showed the lowest impacts for GW and TA, whereas organic medium-yield systems exhibited markedly higher FE due to intensified nutrient inputs. Compared with U.S. benchmarks, French systems in new cropping regions showed roughly double carbon footprints due to low yields. At beer production level, hop use becomes environmentally significant in highly hopped craft styles (4–8 g/L) challenging the assumption that hops are negligible contributors. GIS-based nutrient modelling revealed that hydrological connectivity can substantially alter leaching estimates relative to conventional Tier I–II methods.

Conclusions Hop cultivation can entail relatively high environmental burdens per kilogram of product, particularly when yields are low. Enhancing yields while optimizing fertilizer inputs is therefore essential to reduce impacts in emerging growing regions. By integrating GIS-based emission modeling into LCA and disentangling N and P-driven eutrophication with regionalized factors, this study provides management-relevant evidence to support the optimization of fertilization strategies. It also offers a transferable framework for other agricultural systems in which nutrient losses are a major driver of environmental impacts.