LCA for Food and Agriculture

Food systems are responsible for approximately 26% of global greenhouse gas emissions, 70% of freshwater use, and 50% of habitable land use. Agricultural LCA addresses one of the most impactful and complex sectors, with unique methodological challenges around biological systems, regional variability, and land use.

Why LCA in Food and Agriculture?

Massive environmental footprint: Food production is a primary driver of climate change, land use change, water scarcity, and biodiversity loss.

Consumer interest: Food choices are daily decisions where individuals can influence their environmental impact.

Corporate commitments: Food companies face pressure to measure and reduce supply chain impacts.

Policy relevance: Agricultural subsidies, dietary guidelines, and trade policies benefit from LCA evidence.

Complex trade-offs: Organic vs. conventional, local vs. imported, animal vs. plant protein—LCA helps navigate these debates.

Unique Methodological Challenges

Biological Systems Variability

Unlike industrial processes, agricultural systems vary enormously:

Geographic variation:

• Soil types and fertility
• Climate and precipitation
• Agricultural practices
• Yield levels

Temporal variation:

• Weather-dependent yields
• Seasonal production cycles
• Multi-year rotations

Practice variation:

• Irrigation vs. rainfed
• Tillage methods
• Fertilizer types and rates
• Organic vs. conventional

Functional Unit Considerations

Food products serve nutritional functions, complicating comparison:

Mass-based: "1 kg of product"

• Simple and common
• Ignores nutritional density

Nutritional-based: "100g protein", "1000 kcal"

• Accounts for nutritional function
• Enables cross-category comparison
• Protein quality differs between sources

Serving-based: "One meal portion"

• Consumer-relevant
• Requires portion definition

Land Use and Land Use Change

Agricultural land use raises complex issues:

Direct land use: Occupation and transformation of land for production

Indirect land use change (iLUC): Market effects—increased demand for one crop may push production elsewhere

Carbon stock changes: Converting forest to cropland releases stored carbon

Biodiversity impacts: Land use affects species and ecosystems

Biogenic Carbon Accounting

Plants absorb CO₂ while growing, then release it when consumed or decomposed:

Short-cycle biogenic carbon: Crops planted annually—CO₂ absorbed and released within ~1 year

Long-cycle biogenic carbon: Trees and perennial crops—CO₂ stored for decades

Accounting approaches:

• Climate-neutral approach: Assume uptake = release, net zero
• Full accounting: Track uptake and release separately
• Time-dependent: Consider timing of emissions vs. uptake

Key Impact Categories

Climate Change

Food system GHG emissions include:

Water Use

Agricultural water use is massive but highly variable:

Blue water: Irrigation from rivers and groundwater Green water: Precipitation used by crops Grey water: Dilution water needed to assimilate pollutants

Water scarcity weighting adjusts for regional water stress—water use in water-scarce regions matters more.

Eutrophication

Nutrient runoff from agriculture is a primary cause of:

• Freshwater eutrophication (phosphorus)
• Marine eutrophication (nitrogen)
• Terrestrial eutrophication (nitrogen deposition)

Biodiversity and Land Use

Emerging impact categories:

• Species richness impacts
• Ecosystem services
• Pollinator effects
• Soil quality

These are less standardized but increasingly important.

Product Categories

Animal Products

Beef and dairy typically have highest climate impacts:

• Enteric fermentation (methane from digestion)
• Feed production (often including land use change)
• Manure management

Pork and poultry have lower impacts than ruminants but still significant feed requirements.

Aquaculture and fisheries vary widely:

• Wild-caught: fuel use, stock sustainability
• Aquaculture: feed conversion, disease management

Plant Products

Grains and staples generally have lowest impacts per calorie.

Fruits and vegetables vary with:

• Protected cultivation (heated greenhouses)
• Air freight (highly impactful)
• Water requirements (especially in arid regions)

Pulses and legumes have nitrogen fixation benefits but processing impacts.

Processed Foods

Multi-ingredient products require:

• Recipe/formulation data
• Processing energy
• Packaging impacts
• Distribution and retail

Case Study: Comparative Analysis of Protein Sources

Study Context

Comparing 100g of protein from different sources.

Key Findings

Ranges reflect production system and geographic variation.

Critical Nuances

Beef production systems matter enormously:

• Deforestation-linked beef: 100+ kg CO₂e/100g protein
• Efficient feedlot: 25-35 kg CO₂e
• Extensive grazing on non-arable land: Lower but still high

Co-product allocation:

• Dairy beef comes from the dairy system
• Oilseed protein is co-product of oil production

Nutritional completeness:

• Amino acid profiles differ
• Bioavailability varies
• Micronutrient content differs

Food Waste Considerations

Food waste multiplies impacts:

If 30% of food is wasted, effective impacts increase by ~43%

Impact per consumed kg = Impact per produced kg × (1 / (1 - waste rate))

Waste Stages

Consumer waste is most impactful because all upstream impacts have been invested.

Data Sources and Databases

Specialized Agricultural Databases

Emission Factor Sources

Tools

Cool Farm Tool: GHG and biodiversity calculator for farms Blonk Calculators: Quick LCA for food products OpenLCA + Agri-footprint: Full LCA capability

PCRs for Food Products

EPD International has food category PCRs:

• Food and feed products
• Specific sub-PCRs (dairy, meat, beverages, etc.)

PEF (Product Environmental Footprint) includes food category rules:

• Dairy
• Beer
• Wine
• Pet food (pilot)

Communicating Food LCA Results

For Consumers

Effective:

• Simple comparisons (equivalent servings)
• Relatable benchmarks (km driven, phone charges)
• Focus on actionable changes
• Acknowledge co-benefits (health, cost)

Avoid:

• Overwhelming detail
• False precision
• Ignoring cultural/economic factors
• Oversimplified rankings

For Industry

Supply chain hotspots: Where to focus supplier engagement Product reformulation: Impact of ingredient changes Benchmarking: How products compare to category average Improvement tracking: Progress over time

Key Takeaways

1. Food LCA faces unique challenges from biological systems and regional variability
2. Land use change can dominate agricultural footprints
3. Animal products generally have higher impacts than plant products—but production systems matter
4. Food waste multiplies impacts—consumer waste is most significant
5. Use specialized agricultural databases for credible assessments
6. Communication must balance accuracy with accessibility

Resource List

Databases and Tools

• Agri-footprint
• AGRIBALYSE
• Cool Farm Tool
• Our World in Data - Food Impacts

Key Publications

• Poore, J. & Nemecek, T. (2018). Reducing food's environmental impacts through producers and consumers. Science.
• Clark, M. et al. (2020). Global food system emissions could preclude achieving the 1.5° and 2°C climate change targets. Science.

Industry Resources

• SAI Platform
• World Benchmarking Alliance - Food and Agriculture
• Sustainable Food Trust

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Food LCA is evolving rapidly. Methodologies for land use change, biodiversity, and nutrition are particularly active research areas.